Audio-Visual Glossary



“µ”: The symbol “µ” only looks like a “u”. It is actually pronounced “myu” and is an abbreviation for “micro” (one-millionth). The “µ” is the Greek symbol for the letter “M” - as in the word “micro”. You will see the symbol “µ” on cassette tape decks. An explanation of this symbol as used in tape recording can be found at Nakamichi Front Panel Controls.


µs:  See “µSec”, below for definition.


µSEC:     Stands for MICROSECOND, which equals one millionth of a second.


M:   An abbreviation for:     The prefix, mega (1,000,000).

Usage Note:  The capital “M” always refers to a million but when written as a small “m”, it refers to one thousandth (“milli”).


m:   The small “m” refers to 1/1000th (“milli”). Usage note:  The capital “M” always refers to a million but when written as a small “m,” it refers to 1/1000th.


MAC:      See Macintosh.


Mac HFS:      (This is a term used in the SADiE digital audio computer manual.) An abbreviation for Macintosh Hierarchical File System. “Hierarchical” means, “using a system where items are arranged in order of importance or rank”. The MAC HFS is used in Macintosh computers. It is a way of organising computer files using a tree-like arrangement with a main general topic branching off into more specific files under the same heading. For example, in a Digital Audio Workstation (DAW), a function such as “mixboard” would be the main general topic in the HFS. Under the “mixboard” file, there will be more specific computer functions such as “limiter”, “compressor”, “equalisation”, and “volume faders.” These functions all exist within the main file “mixboard” and are all part of the Hierarchical File System under that file. Each is a “branch” of the main “tree” in the system.


Machine Room:   That room or rooms within a professional audiovisual facility set up with the many various machines used to copy, route, transfer, or produce the programme. This gets the equipment itself, which often has noisy fans, the sounds of spinning tape reels, etc., out of the studio and the control room. Having the equipment in a separate room also allows technicians to work on the gear, operators to run the gear, a nice big air conditioner to blow lots cool of air into the room for the equipment to operate under ideal conditions.



1) Often referred to as “Mac.” A popular series of personal computers introduced by the Apple Corporation in January of 1984. The Macintosh was the first personal computer to use three and a half inch floppy discs. In the 1990’s Mac lost a lot of its market share to other brands of pc’s. And it has moved more into the area of graphics and publishing production, as well as being the platform for A.V. computers such as Pro Tools and AVID.

2) A home audio electronics manufacturer named after its founder.


MACKIE:       A manufacturer of small-sized mixing consoles (mixboards) commonly used for live performances and home or project studios.


MACRODYNAMICS:    Dynamics can be divided into two categories: macro and micro. Macrodynamics are the big crescendos, those moments when the audio builds very loudly overall. Microdynamics, on the other hand, are the subtle volume differences, such as the loudness variations between individual notes on a harp lightly played or in how a pianist hits each key with a certain touch and expression. An excellent audio loudspeaker system can reproduce both types of dynamics and a good recording and mix has these qualities as well. Also called “Dynamic Shading.”


MACROVISION SafeDisc: A type of copy protection for cd-rom’s. SafeDisc installs a digital code onto the compact disc. The code cannot be copied or transferred from the originally purchased cd-rom. The SafeDisc code is designed to cause any coping of the CD-ROM to abort.


MADI:    (Multi-channel Audio Digital Interconnect.) An Audio Engineering Society (AES) standard for the interconnection of 56-channel digital audio signals between mixboards and multi-channel recorders. MADI is the multitrack version of AES/EBU (AES3), though much faster as it is handling many more channels of audio. The MADI interface uses a single BNC video-quality co-ax cable or a fibre optic cable to carry up to 56 channels of audio with a maximum of 24-bit samples.


MAG:      Abbreviation for magnetic.




MAGNETIC CARTRIDGE:  A phonograph cartridge for playing records that generates the audio signal.


MAGNETIC FILM, MAG FILM:  Also called sound film. A type of film - literally just like movie film made of an acetate or polyester base - but used for recording sound. Magnetic film has sprocket holes just as movie film does. It has a ferromagnetic coating covering the entire film or running in stripes along the film’s entire length. The ferromagnetic coating is capable of accepting and reproducing audio signals just as magnetic tape is.


MAGNETIC HEAD:      Often said as “heads”. On a tape recorder, the devices used to apply and-or detect magnetic energy on the tape. An erase head erases the signal on the tape. A record head arranges the magnetic particles on the tape so that a recording is made on the tape. A playback head senses the recorded magnetic patterns on the tape and converts these to electrical energy which then gets amplified so that it can be heard.


MAGNETIC STRIPE, MAG STRIPE: Perforated movie film that has one or more stripes or bands, in varying widths, coated with magnetic tape particles. These stripes, which look very similar to cassette tape, only it is stuck on the film, run lengthwise along the length of the film itself, and is where the sound track is recorded onto. Mag stripe audio has been superseded in our org film rooms by the film audio being put on a digital disk.


MAG STRIPE PRINT: Any film print that has its soundtrack recorded on a mag stripe. (See MAG STRIPE).


MAGNETO OPTICAL DISC:       A digital disc upon which computer information is stored for later processing. It can be constantly added to or erased. It is located inside the computer. It uses a beam of light produced by a laser to do all this - thus it’s an optical disc. The laser can record the data grouped very tightly on the disc, thus a great deal of information can be stored in a small space. The disc is magnetic, and can be erased and written back onto again. Such a disc can be recorded and rerecorded thousands of times.


MAGNETO-OPTICAL RECORDING SYSTEM:        The digital recording-playback system such as is used in the Sony MiniDisc, which can record and re-record high-quality audio on a single disc many times. A laser heats a tiny portion of the magnetic coating of the rotating disc to the point where its magnetic orientation can be easily changed. Then a magnetic head “writes” the new audio information on the disc, which cools as it spins away from the laser.


MAGTRAX:    The brand name of a device that a mixing studio can add to its mixboard which enables the mixboard to be used to mix audio productions in surround sound. If the mixboard is not already configured specifically for mixing in surround, it can be quite a job to try and set the board up to do so. The reason is simply that some mixboards are intended only to mix final stereo (2 channel) releases whereas a surround mix can have 4 to 8 different channels, plus a subwoofer. Trying to get a stereo mixboard to mix in surround sound can be done, but it will tie up large portions of the board’s controls just to get sound to the many additional loudspeakers. Instead, a device, such as that made by Magtrax, can be used. It expands the mixboard’s ability to route sounds to all the needed loudspeakers to do a surround mix.


MAIN FIVE CHANNELS:    An audio mixing term said of surround mixing in reference to the principal channels, loudspeakers heard from the area of the screen and as surround channels out in the room. The main five channels are the Left, Centre and Right loudspeakers in front of the audience; and the Left Surround and Right Surround loudspeakers which are placed on the walls to the sides of the listening or viewing area. Other channels in surround sound systems usually include a subwoofer; and may include additional surround channel loudspeakers on the back wall behind the audience, as well as more channels to either side of the main centre channel comprising five loudspeakers in front of the audience.


MAINFRAME:       A metal frame that holds various pieces of electronic equipment and often supplies them electrical power. These are usually large open metal frames in which equipment can be mounted. Can be for computer, audio or video gear.


MAIN MONITORS:     The large, principal loudspeakers installed in front of any mixing position.


MAIN(S):      1) The main Left and Right full range loudspeakers in a studio or as set up for a major live event. As opposed to any other loudspeakers which may be in use throughout the room. “The mains can play quite loudly.” 2) The power lines coming into a building and more generally, any power receptacle. 3) A principal pipe, conduit or line in a distributing system for water, gas, electricity, etc.


MAJOR, MINOR SCALE:    A scale of notes in music. A major scale does not sound dissonant or moody (dark or dreary) but rather “up”, happy or positive. This is as opposed to a minor scale. You can play a major scale if you find a “C” note on a piano and play 8 additional WHITE keys (notes) in sequence up or down the piano’s keys starting with the C. These white keys are full steps up or down. There are also black keys on the piano. They can be only a ˝ step up or down, compared to the white keys being full steps. Some of those black keys (not every one), if used to replace one or two of the white keys in the sequence (scale) of notes you played above, can make the notes played now sound sort of darkish or dreary. If you played such, you just created a “minor” scale.


M & E:    Abbreviation for Music and Effects. Standard motion picture sound mixing today entails, after the whole mix has been done, preserving a copy of the mix without the dialogue track so that a translated version can be created. This “minus-dialog” mix has the Music and Effects only and can then be used to add any foreign speaking. This “minus-dialog” mix is called a “generic mix” for it can be used to create any language version of the film. Sometimes called the “international version” in the Hollywood film industry.


MANLEY CONVERTER:      Analogue to digital and digital to analogue converters manufactured by Manley Labs. Upgraded by RAV to remove filters that degraded sound quality and to install a solid-state output stage for use on our audio production lines.


MANLEY, DAVID:        A well-known designer of audio electronics for professional and home consumer use. He started the companies “Vacuum Tube Logic” (VTL) and “Manley Labs”. Has retired from active business. David, when he was a working professional studio engineer in South Africa, actually recorded LRH in lectures given there at the time.


MANLEY, EveAnna:    Owner of Manley Labs in Chino, California and an ally of Golden Era Productions - having supplied and serviced a considerable amount of audio equipment used throughout our studios.


MANLEY LABS:    Located in Chino, California. The company that makes Manley professional and home consumer audio electronics equipment.


MANLEY MIC PRE’S:  Microphone preamplifiers which were cooperatively designed and built by RAV and Manley Labs.


MARGIN:      In digital audio recording…The amount of dB (volume of sound) between the highest undistorted peak level of the audio programme and the overload point (distortion point) of the machine. This term is used by Tascam in their DAT machines.


MARK LEVINSON:      The first home audio equipment designer who, in the 70’s came, out with ultra high quality audio gear for the home consumer. Though he lost his company years ago, his name is still on equipment manufactured today by the Madrigal Corporation, a division of the Harmon Group. Mark went on to found the Cello Corporation, which also made very high quality home audio equipment. He recently started “Red Rose”, another audio equipment company in New York. Mark has built custom equipment for Gold, such as for the CLEARSOUND recording rig used for location shooting.


MARSHALL CABLE:     Marshall is a wire distributor located in LA. One is an inexpensive speaker wire for routine installations which is very good. It is called “Marshall Cable”.


MARSHALL (amplifiers):  A brand of guitar amplifier, still made in England, which became popular in the 1960s and has been in use ever since. Marshall amps have a very characteristic sound quality and they have been a rock music standard, with a highly distinctive sound, for many years.


MAS:      An abbreviation for MOTU (Mark of the Unicorn brand) Audio System. MOTU manufactures plug-in software for digital audio workstations. Equipment manuals for DAWs usually state which formats their system will support. If not clearly stated in the manual, the manufacturer should be consulted.


MASH:    MultistAge noise SHaping. The Technics company, who makes a great deal of consumer audio equipment has, for many years, had their own digital system for playing CDs called MASH. Other companies have used it too. You often see “MASH” printed on Technics gear. They won’t tell you the details of their MASH design, but it has to do with how the digital audio is processed to sound more natural. (There are more technical details of the noise shaping process at NOISE SHAPING.)


MASKING:    1) Various sounds can mask other sounds, especially if they are very similar in quality and character. 2) The characteristic of human hearing by which loud sounds take precedence over softer (lower volume) sounds of similar frequency. This occurs because of the untrained ear doesn’t distinguish different sound sources of very similar frequency. The louder, but very similar sound only has to be slightly louder for masking to occur. The principle of masking is heavily used in the audio industry. (See PERCEPTUAL CODING and AUDITORY MASKING for more information.)


MASTER:       1) The actual original recording of a live event or performance - the tape itself is called the master. 2) One of several different final recordings of an audiovisual product one of which is usually archived and not played while the others may be used to create final releasable products. Note:     The term “master” refers to the fields of audio and video, not to film. The “masters” of a film are the original negatives shot inside the camera. 3) To prepare music for final release. Also called mastering. 4) The video or tape recording machine which is used as the main machine (master machine) when using it with another or other machines all synchronised to operate together. The other machines are called slaves. If the master changes speed, the slaves will also change speed in order to stay in sync. 5) The preparation of a glass master for CD or DVD replication. (See MASTERS, TYPES OF)


MASTER CONTROL:   The master volume control or any control which determines the quantity or value of other controls in a system.


MASTER FADER:  The fader (volume control) which controls the overall volume of any mixboard.


MASTERING:       1) The process of taking a final mix and fully preparing it for final release. This can be done by an outside professional Mastering Engineer or at the recording studio, if properly equipped. 2) Mastering is also the name of the process step done by companies who produce large numbers of CDs and DVD’s. It is the creation of the “Glass Master” - the very first master disc, made by a laser, which is then sent through further processing to create the CDs sold to consumers. Mastering takes place in a clean environment, where the encoders use a blue argon laser beam to “burn” pits on a large glass disc coated with a light-sensitive recording layer. Once treated or developed (chemically), the glass disc is referred to as the master or positive. This glass master serves for the production of a metallic master (usually nickel), generally known as the “father”. (It is also called a stamper, if it is used for reproduction of small runs.) For large mass replication jobs, the “father” is used to produce intermediate “mother” moulds which are used to produce the necessary metal stampers (“sons” or “production stampers”) which are used in the injection moulding machines.


MASTERING ENGINEER:  A professional audio operator skilled in doing the final preparations for an audio programme before it is replicated and released to the public. (See MASTERING def #1.)


MASTERING HOUSE OR MASTERING STUDIO:  A studio facility that specialises only in mastering. (See MASTERING def #1.)


MASTER RECORDER: The main tape recorder in a studio that is used to make the master tapes (the final recordings of any mix done.) Some studios will also do original recordings on this recorder as well.


MASTER 6 TRACK RECORDER:       Some mixing studios that work primarily in surround sound, have a recording machine that is used to make a final copy of each of the six channels of a surround sound music or film mix when the mix is completed. (The machine itself may be capable of recording more than six channels, which can be beneficial as surround mixes can have 4 to 8 and even more final channels of audio programme.) The tape, digital or analogue, that this recorder makes can then be taken for mastering or to another studio to do further mixing, such as foreign versions, etc.


MASTER STEREO CLEARSOUND EQ:     This is a large, multi-knobbed unit with many different adjustments and controls to tonally “shape” music or other recorded audio. It is a huge “tone control”, but with numerous separate controls for the bass, midrange and treble. There are many of them so very exact changes and improvements can be made to the sound. It is called a “master” EQ because its sound quality is so high that it could be used for the final preparation of a music release. The units exist in each of Gold’s main music and film studios. They were designed by RAV and built by Gold and are extremely valuable.


MASTERS types of:    There are many different types of master recordings and copies used throughout Golden Era Productions. (See MASTER def #1, #2.) The list below covers the vast majority, and certainly the most major, giving their names and a brief description:  






Lecture Masters



An exact Ľ inch stereo analogue tape copy of a mixed and edited LRH lecture for preservation of the tech. These copies are designated “Edit Master” to indicate that they are exact duplicates of the mixed and edited analogue Edit Master tape, and to differentiate them from other masters



An exact digital tape copy of a mixed and edited LRH lecture for preservation of the tech. These copies are designated “Edit Master” to indicate that they are exact duplicates of the mixed and edited analogue Edit Master tape, and to differentiate them from other masters. The type of machine these are recorded on is called a “DAT machine” - digital audio tape, and so this type of master is also referred to as a “DAT Master”.


DAT MASTER (Digital Audio Tape Master)

A digital master for every LRH lecture is made for preservation of the tech. The approved mix and edit of each LRH lecture is copied on the Digital PM Line. These DAT’s are then used to make the metal records that get preserved for eternity.



This is one of two master copies made of every LRH lecture mix.

(The other copy, made at the exact same time, is called the Edit Master. See Edit Master below.) The Safety Master is actually the final master run-off of the mix and kept secure. It is never edited.



One of two master copies made of every LRH lecture mix. (The other copy, made at the exact same time, is called a Safety Master. See Safety Master above.) The Edit Master is turned over to Lecture Editing and, when edited, is turned back over to the Lecture Mix team who do a final mixing process. (See Final Lecture Mix Master Reverb Runoff below.)



Reverberation is added as a final mixing process for some LRH lectures, as the last step before a lecture product is copied onto its Production Master. The Lecture Mixing Officer determines which ones need to have reverb added, based on the sound quality of each individual lecture. Often a lecture mix done prior to the installation of the CEDAR restoration system will be upgraded before being released on compact disc. In such cases, the Edit Master tape of the prior mix is played through the CEDAR system and an equaliser, then copied onto a new analogue tape. This new tape is also referred to as a Mix Master.



Each translated lecture is recorded directly into the SADiE computer. Once completed, the recording from the SADiE is backed up onto an Exabyte tape to preserve the original recording. The lecture then goes to Editing.



Once the edit for a translated recording is completed in the SADiE and verified as okay by the foreign director, the final edit is recorded internally in the SADiE to preserve the edit of the lecture. This internal recording is called the “FINAL EDIT BOUNCE”. This Final Edit Bounce is equivalent to and supersedes the Ľ inch analogue tape foreign lecture edit master. Once the final edit is completed, the lecture is sent to mixing.



Once the final mix of a translated lecture has been completed, the lecture is then mastered for cassette production. The final mix is recorded from the SADiE through a Dolby B (the type of Dolby used for cassette production to reduce tape hiss). Once this is done, a CD-ROM production master is made. This CD-ROM production master is then used in the Gauss Line Digital Bin to mass-duplicate cassettes. The CD-ROM production master supersedes the 1 inch analogue production master formerly used.



Once an LRH lecture has been completed through mixing and editing, a production master is made. The original analogue mix master tapes of LRH (English) lectures are never used for mass duplication. The mixed and edited master analogue tape is loaded into the SADiE and the analogue master is stored in the A.V. Storage Building. Once in the SADiE, the lecture is recorded through a Dolby B (a brand of equipment that is used to reduce tape hiss on cassettes). Then a CD-ROM copy is made of the Dolby B programme. This CD-ROM is the Production Master. These PMs are made for both English and translated lectures. Formerly PMs were made using big 1 inch analogue tape on a Studer (brand) recorder. The 1-inch analogue PMs have been superseded by the CD-ROM PMs, but the analogue PM line remains intact.


Audiovisual Product Masters



The actual original recorded tape of the audio portion of any audiovisual property or performance. The audio for all Cine shots, narrations, translated LRH lectures, music, sound effects, for any sound recording at all - the actual tape it was recorded to is the Original Recording. It is the direct recording from the microphone or musical instrument. The recording can be analogue or digital and on any present or future sound recording format. It is the original, and irreplaceable, so is inventoried, used with care and kept secure at all times.



The first direct FULL copy of any final music or audiovisual product upon completion of its mix. Includes any film mix, music mix, video mix, TV Radio ad or show, etc. This copy is carefully quality control checked, labelled as the Mix Master, inventoried, and kept securely archived. It may be used by another Gold Studio, such as in the case of music for a film or video mixdown, but is not otherwise passed out. There may be other versions of the mix run off as well, BUT this is the final, exactly as approved. (Note:    Masters for lecture products have their own delineations and are covered elsewhere in this listing.)



Recordings of each song or track for a new music release assembled in proper order. Each separate piece is edited together forming a “Compilation Master”. If the product is intended for cassette release, two reels - one for side A and one for side B of the cassette will be created. Each recording used is taken directly from the mixboard as the final mix is played. The Compilation Master is used to fully prepare final Audio Production Masters for cassette release, or, in the case of digital release (CD, DVD, etc.) it is used to create the Plant Master.



In Audio and Manufacturing, the “Production Master” is the final tape officially turned over by the Studios for mass duplication. It is a direct copy of another master but specially prepared with its contents exactly formatted and at correct volume levels for the intended release format (CD, tape cassette, etc.) It has been fully quality control checked and is a perfect duplicate of the original master to be reproduced. Can be in analogue or digital format. For example, the large 1 inch wide magnetic tape provided to the High Speed Cassette Copy Line for the making of all tape cassette products is a “Production Master” - also called a “PM”.



See Archives Copy Master above.



Companies who specialise in the mass duplication of digital release formats are called “plants” (CD plant, DVD plant, etc.) They have all the specialised equipment required to create these products in high volume. For such a facility, even if eventually done in-house, a specific type of digital master is required that is prepared per exact technical specifications. Such requirements may vary depending upon the plant, its equipment, and the actual digital format chosen for release. The master sent for such duplication is called the “Plant Master”. These may be in several different formats, depending upon the type of release intended. Any audiovisual product, including all lecture products, must first be converted to a Plant Master to be used for digital mass replication.


Specifically in regards to foreign language versions of A.V. products, a “Generic Master” is an internal studio term used to delineate a specific type of final master that has been run off minus the English narration in preparation for adding foreign speaking parts. As the mix run-off (master) is “no language”, it is colloquially called a “Generic Master” and is henceforth used to create all final foreign versions. But note that when each foreign version is completed, a Mix Master is run, in that language.



Any final foreign version of an audio product, such as the soundtrack for a film or video, radio show, TV ad, etc.


LAYBACK (video)

This is an audio term, and it is a final master copy, but it is actually put on a video received from Video Editing. It is the soundtrack added to the video’s pictures and it is always done by rolling a high quality professional video recorder into the studio and copying the mix directly to the audio tracks of the video itself. This video can then be used to create other videos that will be passed over for mass duplication.




Video Masters



The actual videotape recorded from the camera’s direct signal when the shot was taken. It is the master, original image recording. Usually also has sound. (“Beta” and “DigiBeta” are trademarks of the Sony Corporation and refer to a type of video camera and equipment.) Note:  During some shooting situations, particularly at major events, the tape is not put in the camera itself, but rather the camera’s signal is routed to its own professional videotape recorder. Nonetheless, the recorded tape is still referred to as “the Camera Master”.



Once a video edit has been done, using the Camera Masters, the final edited tape created by the Editor is the Video Edit Master.



While the actual Video Edit Master never leaves Editing, but is kept secure per the Editing production line, a direct copy of that master is made - several as a matter of fact. A “clone” is a direct digital copy made with no vias. It is “playback machine to copy machine” using high-grade wiring with each machine perfectly calibrated. The copies are stringently quality control checked. The first clone made is considered the “Protection Master” because it “protects” the actual Edit Master from ever having to be used. It is the Protection Master which is sent to the Audio Division to receive final mixed audio. The other clones are used for foreign versions and back-up copies. Note:     The actual Edit Master itself does receive the final audio mix on its sound tracks, but this is done within Editing by making a direct copy of the mixed audio tracks from the Protection Master.



Though this format is now superseded by DigiBeta, for over 10 years prior, video production involved the use of a Sony video format called “D2”. (See D2 in this glossary.) Any final Edit Master originally done in the D2 format is often referred to as the “D2 Master”.



For international events, a complete audiovisual presentation is done. The entire show or activity is actually edited live, using editing facilities within a production truck. A master videotape recording of this edit is recorded as the show occurs live. Audio is recorded to the very same tape, taken from the truck’s mixboard. This master is called the “Line Cut” because it was edited (“cut”) while the entire show was “on-line” (live). “On-Line” is an old live broadcast term. This master is polished up in terms of editing and final audio mixdown, at which point, a final video Edit Master is created, as well as subsequent clones.


MASTER STEREO FADER: The MAIN volume control on any mixboard that controls the overall volume of the final mix. This can be one fader or sometimes two faders - one for the left stereo channel and one for the right. If it is a surround sound mix, then one fader controls the overall volume.


MASTER TAPE:    The tape that is the final version of what is recorded. All tapes made from this tape are copies.


MATCHING TRANSFORMER:    A device used to match a low impedance source to a high impedance destination or vice versa.



1) A matrix is any network of computers or other electronic equipment combined together for a purpose. The word originally came from Latin meaning “womb”, from “mother”. It has come to mean that everything in a matrix comes from one central source (the “mother”). For example, you can have a matrix of video recording machines or a matrix of computers which are all working together.

2) In the 1970s some audio engineers and-or marketing people decided to use the word “matrix” as regards the creation of surround sound. The term “matrix processing” became known because such systems take a type of stereo (2 channel) audio programme as the “mother” and then from that are able to reproduce a convincing “surround sound” of upwards of 4 or 5 channels. Each of the 4 or 5 resulting channels are not totally separate. They all kind of blend into one another to a degree, and each affects the others. But the matrixing system allows them all to predominately play different sounds so the surround sound effect is effectively accomplished.

3) The usage of the word “matrix” has continued to be used in the audio field as regards versions of surround sound designed exclusively for movie soundtracks played in professional cinema theatres and in home theatres. The original Dolby Surround format (also called “Dolby Pro-Logic” for the home version) is also called “Dolby Matrix” because it took stereo (2 channels) and “matrixed” additional channels to create surround sound throughout a theatre. In the digital surround sound formats for DVD Videos - Dolby Digital Surround, DTS, etc. - a type of matrixing also actually occurs as a DVD really can’t hold 5, 6, or 7 individual audio channels PLUS the picture information for an entire film. These systems digitally condense the soundtracks down to one digital stream of information by an encoding process. The data can then be stored on a DVD together with the film. When the film is played back, a decoding process is done to create the multi-channels from that one matrixed digital stream of information.

4) Any electronics device which allows the one of several inputs to connect to any one (or more than one) of several outputs.

5) Matrixing is used in some types of microphones to create the sound of a large expansive space for a recording. A stereo (left channel, right channel) microphone has an electronic circuit added to it which matrixes (creates) a third channel. These channels are then combined in mixing to produce an audio perception of space in the recording.


MATRIX-ENCODED:   (See MATRIX for derivation and full definition as applies to the surround sound process.) This is the process that converts the older type Dolby Stereo Surround 4 channel (Left, Centre, Right and Surround) signals into 2 channels (Left, Right) of information which is then placed on the film for release. The matrix-encoded version, when played back in a theatre, is “decoded” back to the 4 channel surround sound.




MAXIMUM POWER RATING:   A value that means almost nothing, but is used nonetheless by audio amplifier manufacturers to entice consumers into purchasing their product based solely on “big numbers” of “power”. Technically, it is the maximum wattage that an audio component can deliver or handle as a brief burst during the loudest musical peaks. Most reputable manufacturers will provide both a normal operation power rating and a maximum power rating. Typically, the given value for the maximum power rating is twice to three times that of the normal operating power levels the amplifier is capable of delivering on a general basis.






Mbps:     Megabits per second, also Mbit/sec, which means millions (“mega”) of bits per second, is used mainly with computers and computerised audiovisual equipment, when specifying data transmission, receiving and processing rates (speed - how much data can be handled per unit of time). Note that Mbps refers to the rate of transmission, reception or processing, not the amount of data stored. Kilobits per second, Megabits per second, etc. are used to designate how much data per unit of time can be transmitted, received and processed by computerised equipment. The storage capacity of a given computer hard drive - or medium like a floppy disc - is designated in “bytes” as in Megabytes. Some floppy discs store 1.4 Megabytes. A CD stores 650 Megabytes and a single-sided, single-layer DVD has a storage capacity of 4.7 Gigabytes. A common CD accepts (records) and plays back at a rate of 1.4 Megabits per second. A conventional DVD records and plays back audio at 6.1 Megabits per second and video at 3.1 Mbps. A DVD-Audio player is 9.2 Megabits per second (Mbps) - all allocated to audio data.


M CLASS:      This is a term found in the SADiE digital audio computer manual. An older, no longer made, version of digital audio workstation that was manufactured by AMS Neve. “M” has no significance other than one of a series of models. The AMS Neve M Class workstation was set up for and operated only at 16 bit, 44.1kHz. It was not capable of higher bit or sampling rates.


MDF:      Abbreviation for Medium-Density Fiberboard. This is a type of wood, man-made (but using wood) used to build speaker cabinets. It is very dense and heavy. Ultra-small particles of wood are electronically aligned (made to face in one direction) then they are glued and pressed together to form this thick material. It is also used by many furniture builders.


M-DVD:  Magnetic-DVD.” An early type of recordable DVD introduced in 1998 by Castlewood Systems of Pleasantwood, California and Sanyo (a Japanese electronics company). The M-DVD was a predecessor to DVD-R and DVD-RW recordable discs. (See DVD-R, DVD-RW.) It was the same size as a DVD but could only hold a little under half a DVD’s capacity of digital information. M-DVD has been replaced by the DVD-R and DVD-RW, and is no longer on the market. For more technical information, read on…M-DVD recorded with MPEG2 compression and provided SVHS quality images of 420 lines of resolution. (Commercial DVD’s have 480 lines.) Unlike more recent DVD recorders which “burn” information into a disc using laser light, M-DVD used magneto-resistive recording - where the electrical resistance of a storage medium is changed when exposed to magnetism. The changes in resistance correspond to the changes in the signal being recorded, which are then made into digital information bits.


MEAM:   An abbreviation for Metropolitan Equipment Acquisition Mission. In the late 1970s a Sea Org mission was fired to provide a logistics liaison for the production of LRH’s films and lectures. Over the years “MEAM” evolved into a permanent logistics facility and is located in LA.


MEASURE:    The musical notes which fall between the bars in a piece of music. (See BAR, STAFF.)


MECHANICAL VU METERS:      The type of audio meters that have a needle that moves in response to the amount of sound energy present in an electronic component. They are called “mechanical” meters because their needles physically move. The needle has mass and it moves. Also called “Analogue VU Meters”.


MEDIA:                                                                                           Traces back to a Latin word meaning “interview”. 1) Media is a shortened word for “news media”. 2) In audiovisual, the word “media” is used as a general term for any of the types of recording or playback formats such as magnetic tape, CDs, DVD’s, CD-ROMs, etc. They are all “media”. Media is the plural form of “medium”. One would correctly say, “We purchase all the media required for this week’s studio production


MEDIA AGGREGATION:    The word “aggregate” means, “to gather together into a mass or sum” and is the technical and marketing word used to describe this feature. “The consumer can select a single Hollywood film from the aggregated media stored in the cable TV company’s movie library.” Service providers such as cable TV companies, satellite companies and telephone companies (“telcos”) use computerised equipment that aggregates various types of services that their customers demand. For example, news programmes, movies, sports and talk shows each have their own category in the media aggregation programmes of the service provider’s equipment. These can be sold to a subscriber (customer) in various packages that are tailored to a given subscriber’s personal needs.


MEDIANET:  The name of a fibre optic signal transmission provider employed chiefly for transmitting digital video and audio information. These lines are capable of very high quality picture and sound transmission and are often used by professional studios, broadcasters, etc. Medianet has their own fibre optic cable network principally covering the greater Los Angles area. Its system is geared towards servicing the film and television news industries. Film and video companies often use Medianet’s service to send videos of daily film rushes or news footage to other companies, broadcasters, etc. For example, Channel 7 news might cover a story in downtown LA and use Medianet’s service to transmit their video shots across town to their main studio for editing and broadcasting. Medianet also provides links from live venues to studios and broadcast stations. This service is called “backhaul”.


MEDIUM:      The singular form of media. (See MEDIA.)


MEGABYTE:  A megabyte (MB) is 1024 kilobytes, or 1,048,576 bytes. It’s not just 1,000,000 because it is 1,000,000 in the binary number system. The term is used as regards to the amount of data storage a computer’s discs and internal memory can store.


MEGACHANGER: Refers to CD and DVD changers that can hold hundreds of individual discs. These are made by most electronic manufacturers - Sony, Pioneer, etc.


MHz (MEGAHERTZ): One million Hz. The term “megahertz” is also sometimes incorrectly abbreviated as “Meg”, especially seen when reading advertisements for personal computers and laptops. In computers, the term “megahertz” indicates the speed at which the computer will perform it’s functions.


MEMORY STICK: This is a Sony device. It is literally the size of a stick of gum but it stores digital information such as music and-or pictures. It is a very small computer card that can be recorded and played back on devices that are made to use them. They are made for the home consumer market and can be used to record and play back things such as photographs, music and computer data. (See MEMORY STORAGE DEVICES for full listing.)


MEMORY STOP, OFF, AUTO REPEAT:    A switch found on Nakamichi and some other brands of cassette decks. The “MEMORY STOP” position switch will stop the tape as soon as the counter hits “000”. In “AUTO REPEAT” position the cassette tape is automatically rewound as soon as it reaches its end and played again over and over. The “OFF” position disables the MEMORY STOP and AUTO REPEAT functions. (See NAKAMICHI CASSETTE DECK FRONT PANEL CONTROLS - WHAT THEY ARE AND DO.)


MEMORY STORAGE DEVICES: The following is a list of the more common small memory storage devices used in personal computerised equipment such as digital cameras, MP3 players, etc. Many of these storage devices can hold audiovisual digital information. (Note:     The list below does not list large storage media or devices, such as those used in large personal computers, professional digital audio workstations, etc.)






Technical words and terms used below may be found elsewhere in this glossary.


CompactFlash (CF)

8MB to 512MB; $30-$700, Matchbook-size cards are typically used in digital cameras.


CompactFlash Type II

265MB to 300MB; $400-$450. Thicker version of CompactFlash, used in pagers, net-working devices, fax-modems, etc.



250MB single-sided or 500MB double-sided Micro-optical discs to handle music files, e-books, games, etc. Blank disks expected to cost $5-$12.


IBM Microdrive

340MB to 1GB; $299 to $499. Fits into Com-pact Flash Type II slots. Used in MP3 players, digital cameras, PDA’s and laptops. Largest card can hold thousands of high-resolution pictures, or 1,000 200-page novels.


Iomega PocketZip

40MB; four-pack costs $50. Formerly called Clik, 2X2-inch disk is used in company’s Hip-Zip music player. Fits laptops with adapters.


Iomega Peerless

10GB or 20GB; $360-$400 for disks and base station; $160-$200 for individual disks. PDA-size disks can back up an entire hard drive.


Iomega Zip

100MB to 250MB; Zip drive $80-$150; Zip disks $10-$16.66 in quantity. Popular media used to back up computer files.


Memory Stick

8MB to 128MB; sticks up to 1GB are in development; $30-$240. Sony format used in cameras, camcorders, computers, voice recorders and other devices. A variety of expansion modules are in the works.



8MB to 64MB; $35-$100 Postage-stamp-size storage for cell phones and music players.


Secure Digital (SD)

8MB-64MB; 128MB and 256MB available in 2002; $35-$140. Another stamp-size card for mobile phones, MP3 players, PDA’s etc. The slot is expected to handle Bluetooth, GPS, imaging and other expansion modules.



8MB to 128MB; $20-$160. Older format found in digital cameras.


MEMS:   An acronym for Micro-Electrical Mechanical Systems. The prefix “micro-“ means “one millionth” and indicates extremely small (microscopic) dimensions. This term is used to describe the use of “micromachines” to perform work in many different spheres of operation. These are not just small computer chips that electrons flow through to be amplified or routed in some way. MEMS are actual mechanical devices that move and do physical work, though they are very small like the size of ultra small computer chips. They do physical work or a combination of electronic and physical work, unlike a computer chip which only does electronic work. For example, MEMS now enable microphones to be built that are no thicker than the strand of a single human hair, engines so small that hundreds could fit in the palm of your hand and medical probes that can be threaded through veins. Micromachines require little power to run, so they are ideal for equipment that is battery-powered, such as laptop computers and cell phones. The proliferation of micromachines has much to do with the way they are made. Like computer microchips, the makers of MEMS use silicon as their basic material. Micromachines can be made more complex without adding much cost. “It’s no more expensive to put a million gears on a micromachine than it is one”, per one manufacturer. At this size, silicon is stronger than steel. One government-sponsored lab has built small engines that can make 8 billion revolutions without lubrication. As a comparison, if a tire could be built as reliable, it could be driven the equivalent of 8 round trips to the moon! Since 1961, micromachines have been used in dozens of commercial products. Today, MEMS are being used to switch beams of light and-or data in computerised communications networks, to power booster rockets the size of a quarter, inflate car air bags and to travel through veins to check blood pressure. As the technology of MEMS develops, a new word is used to describe the machines - “Nanotechnology” (“nano-“ meaning one-billionth). Nanotechnology uses the very atoms and molecules of a substance as its building blocks.


MERCURY LIVING PRESENCE:       This is a famous record label for a type of recording done in the late 50s and 60s when stereo audio was first made available. The “Mercury Living Presence” recordings were made by the Mercury company. They used 35mm film, a type of film completely coated with magnetic recording particles just like normal recording tape, to record the performances of the most famous orchestras playing the greatest in classical music. The audio quality, to this day, is stellar, and the original records (LPs) command very high prices. Some may cost several hundreds of dollars and are quite rare. Many audiophiles collect the originals and there is a considerable market for these famous recordings.


MERIDIAN LOSSLESS PACKING (MLP) DIGITAL COMPRESSION:       The Meridian Lossless Packing Digital Compression system (MLP) is how music or other audio information is put onto the new DVD-Audio digital disc. MLP is how the audio digital data is “packed” so as to fit on the DVD-Audio disc. (Note:     This is not used for DVD-Video discs as those only have sound by Dolby, DTS and-or MPEG.) Though the DVD can hold 7 or more times the amount of data as a CD, the DVD-Audio disc is capable of playing 6 channels (or 5.1) of surround sound and that much audio information won’t fit all on one disc - at least not for any acceptable length of time. To give an example, a 5 channel mix on a single-layer DVD-Audio disc, uncompressed without MLP and using only 20 bits instead of the disc’s potential 24 and using a 96k sampling rate, will only hold 65 minutes of audio content. That is not as long as most CDs. Additionally, the DVD-Audio disc is capable of presenting video clips and graphics with the music and these take up storage space on the disc too. To move up to 6 channels of audio at a full 24 bits, 96kHz sampling rate would require about .5X more than the disc is capable of holding. So, there is just not enough storage space on the disc to accommodate the high digital rates desired for DVD-Audio discs. Therefore, compression must be used. However, there are different types of compression. Some, such as the types used to prepare film soundtracks for DVD-Video discs, literally throw some of the music and picture information away. They make room on the DVD by simply not recording everything that there is to record. These types of compression are called “lossy” compression - they “lose" information intentionally. This to a greater or lesser degree can degrade the sound quality. Therefore a way to not lose any information, but still compress the data, was needed. The solution came from a small audio company in Cambridgeshire, England called MERIDIAN Audio. Several other companies tried to develop similar systems, but the Meridian method, after extensive testing by independent engineers, won out. The Meridian Lossless Packing system is the compression method for DVD-Audio discs. This does NOT mean that a DVD has to be processed with MLP, but in order to get any music longer than about 40 minutes for surround and 64 minutes for stereo, at high digital bit and sampling rates, one does have to use MLP. The sound quality of MLP is very high. DVD-Audio is not a Dolby or DTS surround sound format. However, Dolby is the international licensor of Meridian Lossless Packing and controls its use. MLP is used for DVD-Audio, while Dolby and DTS surround process are for DVD-Video releases. MLP is not used on those types of discs. Meridian Lossless Packing is an important part of modern audio production and distribution. It is therefore important to know something about it. In 1992 Meridian’s chairman, Bob Stewart, and several associates worked on various techniques for improving upon storing digital audio on CDs. Then in 1994 he was asked to be the chairman of a committee set up to develop a new standard in digital audio. By 1995 the committee had determined that the format would utilise the just-then created “high density” digital discs (which look like a CD) and that from the disc, one would be able to play multi-channel surround at a much higher bit and sampling rates compared to CDs. Whereas a CD has 16 bit, 44.1kHz rates, the new format would have 24 bits 96kHz - and be capable of 6 channels of sound, not just the CD’s two channel stereo. This is significant information, because it is this committee’s work that really ended up establishing the entire new forward thrust in digital audio - one which also affected how music recording studios were to be set up and the type of equipment they would require. Having established the rates and specifications for the new format in 1994, Stewart then set to work to come up with a way to get all the music information onto the small digital disc - a disc which was not even named at that point. (It was not until 1997 that the DVD was first released - in Japan - and then in 1998 in the USA.) His research was successful. Developed was a method of compressing digital audio information but in a way that never lost any of that information. The digital data could be “broken down” and then “built back up”, bit for bit. Nothing lost. Thus the term “lossless”. Dolby immediately supported the method as did Warner Brothers. And, despite some stiff competition, the MLP method proved to be so good sounding and workable, it was chosen as the method for compressing music for DVD-Audio discs by the music industry. As for how Meridian Lossless Packing works, MLP makes use of the fact that high-rate formats like DVD-Audio carry more information than the human ear can hear. Therefore there is “redundant” information, meaning “excessive” (the original derivation of the word) information. Though the exact technology of MLP is kept secret, it detects the redundant information and “packs” the digital audio data into a smaller space. The music digital data is then decoded when the DVD is played back. The MLP coding method allows a decoder to recover the original signal - the digital information that existed before the MLP process was even applied. It does this “bit-for-bit” - meaning that for every bit “on” or “off’ for every single sample per second, the MLP system is able to duplicate them all back to the way the original sound was.


METADATA, METATAGS:   Metadata is also referred to as “metatags”. The prefix “meta-“ comes from the Greek word meaning “beyond”, “between”, “behind” or “transcending”. In computerised audiovisual equipment and media, “metadata” could be said to be “data about data” or “instructions about data”. Metadata or metatags are digital codes or instructions or even text and-or pictures and sound that exist in addition to the main programme. For audio production, metadata are the various coded digital playback instructions used by a DVD player, Digital TV or receiver that tell the unit how to play a given soundtrack. Coded “metatags” (instructions) are put in the video or sound data stream and this code is used to determine how the audio is played back. There are many things that metatags can do. For example, if you only have a two loudspeaker stereo system, the metatags will tell your equipment how to play the surround sound soundtrack or music mix using only the two loudspeakers. The unit will then automatically convert the surround sound to simple stereo. Or, if the surround mix is a 5.1 channel Dolby Digital surround, and your surround system has only Dolby Pro Logic (4 channels), the metadata will allow your system to convert the surround mix down to just the 4 channels. If the consumer’s audio system lacks a centre channel speaker or subwoofer, the metatags’ data can be used to play the mix anyway. For DVD production, the system is called SMART FOLD-DOWN. There are also units made by Dolby specifically for creating metadata based mix versions for Digital TV broadcasting. There are many other things that metadata can do. For example, metadata can also allow different versions of a TV video show to be viewed by consumers. The home consumer could type in his local zip code and metadata would be used to determine the version for the area in which he lives. In this way, a version of a television show about Dianetics could give full information about the consumer’s local org, mission or Dianetics group. Metatags cannot normally be seen or read by the consumer, but they can often be displayed by going into the menu of the DVD or TV and selecting them. Note: The DVD contains files, much like a computer. For example, A DVD disc may contain several files:     one for its video version (including sound), one for its audio-only version (in the case of a DVD-Audio release), a file to play a stereo version of music on a CD player and a file for Metadata. (See SMART FOLD DOWN, DOLBY E, DIGITAL TV for more information.)




METAL TAPE:       Cassette tapes are manufactured with various different particles used as their magnetic material. “Metal tape” is the highest quality cassette tape and is the type used for LRH lectures on cassette. The metal used in metal tape is iron. This is different than ferric tape that has iron oxide (rust) as its magnetic particle. Metal tape uses iron that is chemically treated so it doesn’t rust.


METALLIC COATING (for CDs and DVD’s): A term used in regards to the mass duplication and production of CDs and DVD’s. After injection moulding and cooling, each disc undergoes metallising - a process that gives the CD a metallic coat and its typical shiny metal look inside the disc itself. This shiny surface reflects the laser light during the read process. For mass reproduced CDs, this coating is generally aluminium, but CD-Recordable, Write-Once and Rewritable discs use a gold-based coating for the same purposes. Some “audiophile” CDs also use gold as well.




METER:  A device which measures or compares electrical signal(s); often used to read the voltage level of audio signals.


METER BRIDGEA structural section (“bridge”), usually spanning the top of a mixboard, that houses all the meters one uses to judge audio volume levels.


MEYER:  A company near San Francisco, California that specialises in making loudspeakers, named after its owner John Meyers.


METALLIC:    When recorded or reproduced sound has a metallic quality, it sounds as if sound is reflected off metal - meaning that the upper midrange and highs are accentuated and the sounds are a bit hard sounding (uncomfortable). It is a quality imparted to the sound which has an undesirable brightness - excessive treble frequencies.


METRONOME:      Comes from the Greek words “metron” meaning “measurer” and “nomos” meaning “rule or law”. A device used, especially when practicing a musical instrument, to keep precise timing while playing or singing. It makes very steady clicks or tick sounds and these can be adjusted for any speed.




MF: Middle Frequency(ies), the midrange. The majority of music and voice occurs in these frequencies.


MIC BREAKUP:    The sound of severe distortion, often a sharp cracking sound as if something in the microphone has actually snapped (“broken up”). Microphones can sometimes “breakup” if they are hit with too loud a sound. There are two ways this can occur. The first is where the sound hits the part of the microphone that changes air vibrations into electrical vibrations, called the mic’s diaphragm, so hard that it bends way out of shape and distorts the sound. The other is when the microphone’s electronics, which are immediately following the diaphragm, are not designed to deal with so much volume either, and they overload and distort the signal. Microphones usually have specifications written in their manuals as to how many dB SPL (sound pressure level) they can handle. This gives a guideline, but is not a substitute for testing and being familiar with a given type of microphone. For example, if a microphone that was rated at 100 dB SPL is used to record a jet plane taking off at close range (which is a lot higher in volume), the recording will be useless no matter how impressive the live sound actually was.






MICKEY MOUSING:    In arranging music for audiovisual products, “mickey-mousing” means to skilfully shift the timing of the music to match an action or actions that occur on the screen. The term comes from Disney’s “Mickey-Mouse” cartoons where the music very often was placed in time with the animated cartoon action.


MIC PREAMP:      A high quality microphone amplifier used to boost the very low volume that a microphone originates after it has picked up the sound. It is called a pre-amp because the volume is so low coming from a microphone that it first needs an initial boost before being recorded or going to a mixboard. Often a mixboard has built in microphone preamplifiers for each channel to accomplish this.


MICROBAR:  This is a unit of measurement of atmospheric pressure. One sees this term on the specifications of microphones. Because microphones respond to very small changes in atmospheric pressure, such a unit is used. A microbar is one millionth of the normal atmospheric pressure, which is 15 pounds per square inch. It comes from the words “micro” meaning one millionth and “bar”, which is derived from the Greek work meaning “weight”. One microbar = one dyne per square centimetre. (See DYNES PER SQUARE CENTIMETRE.)


MICROCHIP:       Inside a computer are devices called “microchips.” Also called “microprocessor.” A microchip has an incredible amount of electronic circuitry which has been condensed down to a super small size (“micro”). “Microchip” is just an electronics industry slang term for a circuit that has been imprinted on silicon and that can perform a number of operations. These are bits of silicon that has been packaged into a tiny electronic circuit that resembles a rectangular chip of plastic. “Micro” refers to its very small size. Most microchips can easily fit into the palm of your hand and some are even smaller than a fingertip.






MICROFARADS (mF):       A measurement of capacitance. (See CAPACITANCE.)




MICROPHONE:    An electronic device used to pick up sound in the form of air vibrations and to convert the air vibrations into electrical vibrations. Once in the electrical form, sound becomes a signal that can be amplified and changed by various audio equipment. The precision with which the microphone can translate the air vibrations into electronic vibrations that replicate the sound as heard in the physical universe determines the quality of the microphone.




MICROPHONE CABLE, MIC CABLE:       The wire specifically made for passing the sound signal of a microphone. It plugs into the mic and routes its signal to a microphone pre-amp.      


MICROPHONE CAGE: When recording sound for a film or video, it is sometimes necessary to use a miniature microphone called a “lapel mic”. These lapel mic’s usually need to be completely hidden from the camera’s view. The places to hide lapel mic’s include putting them under a layer of the performing actor’s costume. However, when clothing rubs on a microphone, a very unwanted rustling noise results. LRH, knowing this fact well, advised a way to handle such noise by placing the lapel mic inside a tiny “bird-cage” to prevent an actor’s clothing from rubbing directly on the microphone. In the late 1980s, considerable work was done to carefully prototype and make precisely what LRH advised. Finally a jeweller was able to manufacture exactly what was needed out of a metal used for making jewellery design models. It held the microphone by tightly fitting its wire into a little holder. The back of the “cage” was flat so that it would rest against the actor’s body. It’s a very small cage, about the size of an average thumb above the joint - because the microphone itself is very small. The front of the cage is curved outward to keep the clothing off the microphone but to also give some air space between the clothing and the microphone - which improves the sound. This was one of the most important parts of the design. A tiny hinged door allows the cage to be opened and closed for access to the mic. A sharp pin attached to the cage allows it to be pinned to the actor’s clothing. The microphone cage is dipped in a rubber liquid then sprayed with anti-static spray. The specific type of microphone used with the microphone cage is a modified version of the Crown (brand) PZM (model). (See PZM.)


MICROPHONE INPUT:      An input on a mixboard or other equipment designed for plugging in sound signals from a microphone. (Compare LINE INPUTS.)


MICROPHONE LEVEL, MIC LEVEL: A term used to describe the very low volume of sound signal that comes directly out of a microphone. Also it is a term for the adjuster (knob) for the volume of the microphone’s sound as it enters a mixboard or other audio device.


MICROPHONE PRE AMPLIFIER, MIC PRE, MIC PRE-AMP:     A special amplifier that is specifically made to boost the low-volume sound signal which comes from microphones. The mic preamp increases the volume of the microphone to a level that can be accepted by other audio equipment.


MICROPHONE SNAKE:      Another term for snake. (See SNAKE.)


MICROPHONE TRANSFORMER:      A device that is used to match the impedance of a microphone to the impedance of the amplifier to which it is connected. It may be to match either a low to a high impedance or high to low.


MICRON:      One millionth of a meter, or a thousandth of a millimetre. Used for such matters as measuring the precision surfaces on recording machine parts.


MICROPHONIC or MICROPHONY: Electronic parts inside some audio electronics equipment can literally vibrate when an electronic signal is sent through them. Sometimes they can vibrate as well just by loud sounds vibrating the equipment itself. These vibrations, just like a microphone’s internal parts vibrate to make sound, can also cause tiny sounds and distortions which are in fact audible. Vacuum tubes, sometimes used in audio amplification equipment, can often create this problem as they have small filaments inside, just like a light bulb has and these can vibrate.


MICROPROCESSOR:  This is really just another name for “microchip” however, manufacturers of the most powerful types of these chips, call their product a “microprocessor” as they are used as the central heart of a computer and perform all its processing features and capabilities (e.g. Pentium Processor). The rest of a computer is really just data storage and routings in and out of the microprocessor and the digital storage inside the computer. Inside a computer or any computerised equipment, such as digital mixing and video gear, are devices called “microprocessors” - also called “microchips,” “chips,” integrated circuits, etc. Microprocessors are sometimes called “engines.”


MICROSECONDS, MICROSECONDS EQ:       Also written “µs" or ([Added by Myk] incorrectly) “µsec”. One millionth of a second. (See 70 µSEC EQ, 120 µSEC EQ for meaning in regards to EQ [equalisation].)


MICROSOFT:       The word’s largest computer and computer software designer and supplier.


MICROSOFT FRONT PAGE:      Microsoft software specifically for creating (authoring) a Web site.


MICROSOFT MEDIA 8, MEDIA PLAYERS:     Microsoft’s software system for streaming video and audio information over the Internet. (See STREAMING.) There are portable players that support this method and system of downloading and playing back video and audio information from the Internet.


MICROSOFT’S ULTIMATE TV:  Microsoft’s software and any related items which enable digital video recording, e-mail and Internet over television.


MICROSOFT WORD:  The word processing programme software sold by Microsoft and included in most computers. Often called “Word”.


MICROWAVE:      A microwave is a short radio wave. It varies from 1 millimetre to 30 centimetres in length. Microwaves travel in straight lines, and can be reflected and focused. They pass easily through rain, smoke and fog, which block light waves. They also pass through the upper atmosphere of earth, making them excellent for sending and receiving satellite signals. Microwave was first used in radar systems in World War II. In audiovisual fields, microwave is used for broadcasting, as well as transmitting communications signals. The transmitting and receiving antennas must be in an unobstructed line from one to the other. They are usually placed on the tops of mountains or tall buildings to achieve the required line-of-sight signal path. There can be many miles between the transmitter and receiver as long as there is no obstruction interposed.


MID BASS:    The range of frequencies from 40-80 Hz. The segment of the audio frequency spectrum covering sounds produced in the upper bass and lower midrange region.


MIDDLE AREA:    A DVD can be single-layer or double-layer, and single-sided or double-sided. The transition area in between the layers is the middle area - the space at the end of layer 0 and beginning of layer 1. When the DVD’s laser moves from one to the next, there will be a slight pause in the picture.


MIDDLE HIGHS:  The range of frequencies from 2.6 - 5 kHz.


MID FI:  Inexpensive home audio equipment. Not the cheapest or worst (that is called “Lo-Fi”) and usually okay for some applications. But the sound quality it creates is nowhere near what “Hi-End” equipment produces. (Compare Lo-Fi and Hi-End and HIGH FIDELITY.)


MIDFIELD, MIDFIELD:      1) Said of the position of loudspeakers when they are not right up close, but also not far away - they are “midfield”. In a recording studio’s control room, midfield speakers are placed just in back of the mixboard, but closer than the usual position for large main speakers (monitors.) 2) Said of audience seating that is midway back in the auditorium.


MIDI:     Short for Musical Instrument Digital Interface, which is a digital information signal used only to hook up and control different digital musical instruments. For example, one electronic keyboard can control many other keyboards by hooking them all up with a MIDI wire that has MIDI data flowing between the networked keyboards.


MIDI CONTROLLER:  This is simply an electronic keyboard or other device which can activate a synthesiser. It can make no sounds on its own and has no synthesiser as a part of its internal working. It uses midi information to trigger (make play) the synthesiser’s sounds.


MIDI CLOCK:       Allows instruments interconnected via MIDI to be synchronised. The MIDI Clock runs at a rate of 24 pulses-per-quarter-note. (See MIDI.)


MIDIMAN:    A very small type of mixboard that can almost fit in one’s pocket - and the quality is quite good. Some models have amplifiers for microphones.


MIDI MIXING:    MIDI” is an abbreviation for Musical Instrument Digital Interface. Before a song is ready to be recorded, a lot of preparatory work is done during Sound Designing. With a MIDI system, several different digital musical instruments (synthesisers) are hooked together and controlled from a single keyboard. Before these instruments are recorded onto audio tape, or any other medium, some preparatory steps are usually done such as selecting the combinations of sounds that will play, their relative volumes and how each instrument will be positioned in the stereo or surround sound mix. These preparatory steps, when done using a MIDI system, are called “MIDI Mixing”. By getting all of these basic steps done before final recording and mixing occurs, much time is saved in the mix room.


MIDI TIME CODE:      MIDI time code was developed in 1987 as a means of synchronising musical audio equipment. It is simply a code that computerised musical equipment can read and then use to operate together in time.

For more technical information, read on… MIDI time code uses an absolute time reference scheme (hours, minutes, seconds, frame number), just like SMPTE time code. Originally, there was no time code-like system for specifying absolute time with MIDI. Basically, it was more common for MIDI-based musicians to refer to "the X-th beat of bar Y" than to "X minutes, Y seconds, frame Z”. However, MIDI became increasingly used in the fields of video and recording. Professionals began to demand a SMPTE-like precise, absolute time reference scheme for MIDI. Many different messages are specified in the MTC standard, but the actual time code is the "quarter frame message”. Different frame types are also supported. MTC involves transmissions of large amounts of data, so MTC-specific input connectors are normally provided. Other non-MTC MIDI data (such as controller change messages) is received separately, allowing for stable synchronisation. (The master equipment does not send non-MTC data when running.)


MID HALL PERSPECTIVE: What a listener in an audience would hear if he were seated in the middle of the hall as opposed to being close to the stage (“front of house”). Mid hall perspective is used to describe how a recording and mix is heard by a listener. Some put the listener very close to the “stage” and others have the listener a ways back from the sound:    “mid hall”. (Compare AUDIENCE PERSPECTIVE, FRONT OF HOUSE.)


MIDRANGE:  The segment of the audio frequency spectrum between the bass and treble frequencies. The midrange includes most voices and the fundamental tones produced by most musical instruments. Midrange loudspeaker drivers reproduce sounds in this frequency range. The frequency range above bass but below treble that carries most of the identifying tones of music or speech. It is from 200 Hz to 4 kHz.


mil: One thousandth of an inch. Used for such matters as measuring the thickness of recording tape or the diaphragm inside a microphone which vibrates to create sound.


MILLIAMP:   One thousandth of an Ampere. Used for such matters as measuring the specifications of small electronic parts in audiovisual equipment.


MILLIHENRIES (mH):       A measurement of inductance. See INDUCTANCE.




MILLISECOND:    One thousandth of a second.


MILLIVOLT:  One thousandth of a volt.


MILLIWATT: One thousandth of a watt.




MINI CD (music):      A smaller version of the CD holding less audio but at the same 16 Bit, 44.1kHz Sampling Rate. Will play in most CD players. (See CD TYPES OF for full listing of current names and-or types of CDs and what they are.)


MINI DV:      Miniature Digital Video. This is a type of digital video camera and playback system now commonly used by many home consumers. The cameras are very small and can take moving as well as still pictures.


MINI JACK, MINI PLUG:  The very small plug found on portable CD players, cassette decks, etc. for personal headphones.


MINIMALIST, MINIMALISTIC:       1) A recording and-or mix can be minimalistic if it has only one or just a few instruments or singers alone or if the recording was done very simply using only one or two microphones and if the mix was done without much in the way of processing or changing the sound. 2) Re:   electronic circuit parts design. To keep circuit parts as simple as possible for quick reactions to audio signals so as to allow best reproduction of the original sound. Minimalistic designers try to create electronic circuits for audio reproduction and recording that have as few parts as possible.




MIPS:     Millions of Instructions Per Second. A common measurement of computer processing speed. Even audiovisual equipment that has digital processing is measured by such. Some better home surround sound receivers and processors have upwards of 180 MIPS of computer power.


MIRROR IMAGE: Said of loudspeaker designs. Some pairs of loudspeakers have two or more individual loudspeaker elements mounted in their cabinets. These individual units are called “drivers”. It is not uncommon to mount the drivers in such a way that they are not perfectly vertical, one directly above another, but rather one or more drivers are mounted off to the side within the cabinet while another or other drivers are centrally mounted. When this design method is used, the left loudspeaker cabinet and right loudspeaker cabinet will be made to “mirror” each other - meaning that they will be built opposite to each other. If the tweeter is mounted to the left on one cabinet, it will be mounted to the right in the other cabinet. This helps to stabilise the imaging and soundstage presentation of the loudspeaker. (Compare BOOK MATCHED.)


MIXDOWN:   The process of putting together the individual sounds of an audio programme into a final surround sound, stereo or mono mix. This results in a completed soundtrack for an A.V. product. It’s called a mixdown because the many different sounds are all combined (“mixed”) from their various sources and channels on a mix board down to the final amount of channels of the final product. For example, 48 or more channels of individual set sound, sound effects, voiceovers and music for a film are mixed down to 5.1 surround channels.


MIXER : 1) Short for mix board. 2) The software features in a computerised digital audio workstation that perform mix board functions. For example, the “mixer” section of SADiE has separate channels for processing and combining individual instruments or sounds into a final mix, all within the SADiE computer. SADiE’s mixer can be brought up on the computer screen. It looks like a real mixboard and is used to adjust the volume, frequency balance (EQ) and other characteristics of the sounds within a mix and the mixer combines and blends each individual sound into a completed mix or final soundtrack.


MIXING CHAIN:  The group of equipment, connected in sequence that a Mixer uses to process a sound to get a product. Several pieces of equipment are often sometimes used together. They are called a “chain’ or “the mix chain”.


MIXING CONSOLE:    Another name for mixboard.


MIXING PLANES:       Some Mixers refer to the zone of sound created by two loudspeakers as a “mixing plane”. This plane has 3 dimensional potential - depth, height, width, etc. When mixing in stereo, with two loudspeakers, there is one plane, but when moving to surround sound mixing, where there are many pairs of loudspeakers, there are more planes.


MIX MAGAZINE: A famous magazine, issued monthly for free to professional audio personnel. They do numerous equipment reviews and keep all professionals abreast of the latest techniques, equipment, and developments in the industry.


MIX MASTER or FINAL MIX MASTER or FINAL MASTER:        The first direct FULL copy of any final music or audiovisual product upon completion of its mix. Includes any film mix, music mix, video mix, TV, Radio ad or show, etc. This copy is carefully quality control checked, labelled as the Mix Master, inventoried, and kept securely archived. It may be used by another Gold Studio, such as in the case of music for a film or video mixdown, but is not otherwise passed out. There may well be other versions of the mix run off as well, but this is the final, exactly as approved. (See MASTERS, TYPES OF for a full list of all masters used at Gold.)


MIX MINUS OUTPUT:        A feature of broadcast mixboards that allows a commentator or announcer to receive the audio signal of the programme he-she is commentating on or about without hearing his or her own voice - only the other sounds, such as music, sports game, etc. For example, a live news reporter on the scene of the Rose Bowl Parade needs to be able to hear the audio for the programme he-she is contributing to. The sound engineer at the studio (who could be on the other side of the country from the parade) sends the sound of the programme to the commentator, who hears it through an earpiece while he speaks in front of the TV camera. Of course, because the audio in the announcer’s earpiece has been transmitted to him from a long distance away, it is slightly delayed. If he or she were to also hear one’s own voice mixed too, there would be a slight delay compared to present time. It would sound, to the announcer, like he or she was having to talk out of time - it would sound like a bit of an echo, a repeat which would make it very hard to announce or commentate on top of. The commentator would hear his-her own voice coming back delayed by a few fractions of a second due to going up to a satellite and coming back down. It would be very distracting. To handle this, the sound engineer sends the commentator a “Mix Minus” output - (minus the announcer or commentator’s own voice.)      


MIX ROOM, MIXROOM:    See CONTROL ROOM. (It’s the same thing.)




ML-14:   Model number for a high-quality preamplifier manufactured by Mark Levinson.




MLSSA SYSTEM:  This is a computerised audio measurement device. Pronounced "Melissa”. Stands for Maximum-Length Sequences System Analyzer. Trademarked name by DRA Laboratories (Sarasota, FL). Measures the audio acoustical properties of rooms. For more technical information, read on…Maximum-length-sequences methods were used for room impulse response measurement by M.R. Schroeder in 1979 (based on work dating back to the mid-60's); however, it was not until 1987 that the use of MLS became commercially available. The first MLS instrument was developed and made practical by Douglas Rife, who described the principles in his paper, "Transfer-Function Measurement with Maximum-Length Sequences”, and followed up with new applications described in "Modulation Transfer Function Measurement with Maximum-Length Sequences”. Further information available directly from DRA.


MMCD:   An abbreviation for Multimedia CD. Said of CDs that include text, sound, and motion video for informational, educational, and entertainment products which are then played over personal computers. This is an actual compact disc format whose use has also helped define the new term of “infotainment”. Includes the newer “interactive CDs”, which allow consumers to involve themselves in the programming of the CD. These are played on personal computers having a CD or DVD Drive. Multimedia uses CD-ROM as its main file storage device. It uses a lower quality digital recording method than audio CDs. And, since video files can be very large, multimedia has led to the growth of specialised methods of getting the information onto the CD disc, much like DVDs are now being prepared but with far less information stored. (The CD has much less storage capacity than a DVD, thus the sound and picture quality on MMCDs is poor.)


MOD:      Abbreviation for modification.


MODE(S):     1) A function or setting on an audiovisual piece of equipment. “Please take the machine out of rewind mode.” 2) A manner or way of acting, doing or being:    method or form. 3) Regarding the physics of sound:    Any of various patterns of sound reflections in a room which cause an unnatural build-up of volume at certain frequencies in certain locations within the room. Modes have to do with the size of the room as well as other factors. (Compare NODE.)


MODELING (DIGITAL):    Digital audio equipment is now available that can literally “model” (make a copy of, emulate) different types of audio equipment and its sound characteristics. For example, there is equipment now that will “model” any type of microphone by any manufacturer, even old famous brands and types. There are modeling amplifiers for use by guitarists which will create a sound just like older (“vintage”) amplifiers and guitars.


MODEM: (Modulator-Demodulator). A device that converts digital signals from computers into analogue signals for transmission across regular telephone lines and then reconverts analogue signals from the telephone line into digital signals for use by the computer. Modems enable transmission of computer data through telephone lines. When computer or any digital information is to be sent on a phone line such as the Internet, the digital data has to be converted into analogue signals. The “speed” of a modem determines how long it will take to process and transfer a computer file. The providers of Digital TV via cable use “cable modems” for the transmission of Digital TV and related information over cable wiring. (Note: There are other types of modems that deal strictly with sending information digitally. Technical information regarding such is provided later below.)

For more technical information, read on… Before such data can be sent on a telephone line, the digital information is sent through a modem where it is converted (“modulated”). The digital data is turned into two separate and specific frequency tones. The digital “1’s” become one tone at a certain frequency and the digital “0’s” become a tone at another certain frequency. These tones are then able to be accepted and transmitted by a telephone line. At the other end of the line, where a person wants to receive the data, the telephone line is plugged into a modem that converts (“demodulates”) the two tones back into digital 1’s and 0’s. A modem uses a process called FSK (Frequency Shift Key). The digital 1’s are at one frequency and the digital 0’s are another. The tones (frequencies) simply shift back and forth rapidly to emulate the digital bits. The word “key” here is just a spillover from the days of the telegraph when messages were sent using a telegraph key. Most modems are not capable of compressing and-or decompressing data. However, there are newer versions of the modem which are capable of compressing and decompressing digital data streams. These newer modems are able to then process and transfer data faster. Speed ratings are designated in “bauds” (See BAUD.) Typical rates are 1200 baud, 2400 baud, 9600 baud, 14,400 baud and so on. An internal modem can be built in to a computer and an external modem can be connected to a computer through the RS-232 serial port.




MODULATION:    The process of varying the amplitude, frequency, or phase of an electric current in order to impress on it changes representing the signal to be recorded or transmitted.


MODULATION NOISE:      A hiss or other extraneous noise which "rides on" the main audio or video signal, varying in loudness according to the strength of that signal.


MODULE:      A group of circuits and controls which are mounted on a removable housing, such as a channel on a mixboard.


MOGAMI:      Brand name of a manufacturer of high-quality audio cable.


MOM:     Abbreviation for Mail Order Manager. This is a computer programme for subscription and catalogue services. The mail order management computer registers the order, allows access to the service, bills the subscriber, registers demographic information, etc.


MONAURAL or MONOPHONIC or MONO:    The word “monaural” comes from "hearing with one ear”. The term started in the late 1800’s when the word ”mono” (meaning “one”) and “aural” (meaning “of the ear”) were combined. Monaural means that one is listening to all sounds but only over one loudspeaker. It also can mean that all sounds are heard in two or more loudspeakers but each individual loudspeaker playing all the sounds to be heard. Monaural means there is only one sound source or that the sound is being derived from a single sound source. Example:     A recording of a human voice is sent to two loudspeakers. The sound heard over the two loudspeakers is considered “mono”, even though two loudspeakers are in use. This is because the sound is exactly the same from both speakers - it is the same sound originated from the same source, no matter how many loudspeakers are used. Likewise, if only one loudspeaker is used, it is playing all the sounds to be heard. It too is monaural (“mono” for short). Also, when there is just one channel (track) on a tape recorder used to record all sounds or a single sound it is said to be a “mono recording”.


MONITOR, MONITORS, MONITORING:       1) To “monitor” means to check things for accuracy. One looks or listens to monitor their accuracy and quality. 2) In the field of video, a monitor is any TV or video screen one watches to ensure a high quality product is being produced or broadcast. Video monitors are not technically “TVs”. They look like a TV, but they do not have the electronics with which to actually receive any TV programme from the air. They are only made to be hooked up in a studio or broadcast production truck or other professional application, to watch what is being produced, copied, or broadcast. They are professional screens and very accurate. 3) In audio, a monitor is any loudspeaker that is of professional quality and usable to verify the sounds being produced, copied or broadcast are correct and of high quality. 4) The action of monitoring - using a loudspeaker or screen professionally to check for accuracy.


MONITOR MIXER:      1) A mixboard that blends audio signals used for sending the mix to the monitor loudspeakers or earpieces on stage for musicians (or other listening purposes). 2) The section of the mixboard that is used to do a rough mix so the engineer can hear what is being recorded without affecting the levels being fed to the multitrack recorder. 3) The audio technician who mixes the signals sent to the stage monitor loudspeakers or earpieces.


MONITOR SEND:        An output from the mix board that sends audio to the monitor loudspeaker amplifiers. There is usually a volume control associated with this function of the mixboard.


MONITOR SPEAKER, STAGE MONITOR:      1) A loudspeaker used to gauge quality in a recording, mixing or broadcasting studio. 2) A loudspeaker that is used by those on a stage to hear what they are doing and what others are doing.


MONO BUTTON:  A button or knob on a mixboard or other audio equipment which allows one to hear the audio programme in mono as opposed to stereo or surround sound.     


MONO BLOCK:     An audio amplifier that has only one channel and is meant to drive only one speaker (the left or the right in a stereo sound system). Rather than having a stereo amplifier (two channels in one chassis, with both channels sharing the same power supply and electricity from the wall outlet), two “mono blocks” are used. Each mono block has its own power supply and its own feed from the wall outlet. Mono blocks almost always sound better than using a stereo amplifier. Some stereo amps can be “bridged” so their two channels can work as one. (See BRIDGED.)


MONO MIX, MONO FILM MIX:        A mixdown of any audio programme which only has one channel of information, even if it is meant to be played on more than one loudspeaker, in which case, each loudspeaker would play that single channel of audio information.


MONO CHECK:     When an audio recording or mix is done, it is important to check what it sounds like when played over just one loudspeaker, as that is how some public will hear the product. For example, many radios only have one loudspeaker - they play only in mono. NOTE: If the sound suddenly loses a lot of bass (low frequencies) when the mono check is done, then there is a technical problem (out of phase) and this MUST be checked out and handled. Mono checks are also done over headphones when mixing to ensure that the speaker or singer’s voice is precisely located in the centre of the mix (centre of the head when heard over headphones). One puts on headphones and listens for a moment in mono to the voice, and then switches to stereo. If the centre image of the voice jumps to the left or the right ear over headphones, the stereo mix does not have the voice precisely in the centre so it will always sound “off to the left” or “off to the right”. One gets the voice dead centre by adjusting the volume of the sound in either channel to ensure it is centred by doing the mono check. This can be done for any sound the Mixer wants to ensure is perfectly located in the centre of the mix.


MONOCHROMATIC FILM, MONOCHROME:  (First see FILM and EMULSION for basic definitions.) Monochromatic is a very early type of film, first used prior to 1918, and produces an extreme black and white image - one that has very little gradation from light to dark. The prefix “mono-“ means “one” and the suffix “-chrome” means “colour”. Monochromatic film is a type of black and white film that is sensitive to only one colour of light - blue - and is not sensitive to the red or green part of the visible light spectrum. Note that although it is sensitive to blue light, this does not mean the resulting image will be blue. The film’s emulsion reacts to blue light and eventually forms a black and white image on a film print. The images on monochromatic film are very limited as to the differences in brightness they will show. They look severely black and white, with virtually no shades of grey in between. The silent movies shot in the early days of cinematography used monochromatic film, and their distinctive look is due greatly to the use of monochromatic film in their production. Monochromatic film is still in use for some applications by still photographers who want to produce pictures that have very black blacks and very white whites, with no shades of grey in between. Monochrome motion picture film is no longer made, and those who want its look for black and white cinematography use panchromatic cine film. (Greater or lesser degrees of contrast are achieved with lighting and film lab developing and printing.) (Compare BLACK AND WHITE FILM, ORTHOCHROMATIC, PANCHROMATIC, COLOUR FILM.)


MONOPOLE: A monopole loudspeaker has only one (mono) side containing speakers in its cabinet. This side faces the audience. There is another type of loudspeaker called a dipole (“di” means two). This type of speaker has loudspeakers located in the cabinet which face in two directions - front and to the rear. Dipoles are often specified for the surround loudspeakers used in home theatres. Monopoles are the design that most people listen to when the loudspeakers are placed in front of them. Either may be used for surround loudspeakers around the room - it is up to the system’s designer. Some large rooms need monopole surround speakers to better direct the sounds out to the audience as dipoles are mounted in such a way that the two surfaces of speakers in the cabinet fire sideways along the walls and not directly out into the audience. Sometimes dipole loudspeakers have their two sides angled so some direct sound does get out to the audience. In a very small room dipoles may help make the room sound bigger as they throw their sound all around the room.


MONOTIMBRAL: Said in regards to musical instruments which when a key or note is played, only one sound may be played at a time. Older music synthesisers were often monotimbral. Compare this with Multitimbral - able to play more than one sound at time with one key.


MONSTER CABLE:      Brand name of a very high quality type of cable. We use several different types of Monster Cable on our lines. Some of the more common types of Monster Cable used at Gold include:










M1000S (Silver Super VHS cable for video)

M2000HDSV (High Definition Silver Video cable - for SVHS)


MOOG:   A brand of synthesiser. Named after its inventor Robert Moog. Moog’s pioneering work in the use of electronic circuits to create sounds gave a whole new dimension to the music industry. Popular rock groups started to incorporate this instrument into their songs by the early 1970s. One of the first major popular music groups to utilise the Moog synthesiser was Emerson, Lake and Palmer whose 1971 hit “Lucky Man” featured Keith Emerson on the Moog Synthesiser.


MOORE’S LAW:   Many years ago, Gordon Moore, the cofounder of Intel, made a prediction about how much the capacity of computer chips would increase each year. He predicted that the number of transistors that could be put into the operation of a single chip would double every year. His first prediction, made over two decades ago, proved to be factual. In the late 1980’s he made another prediction that chip capacity would yet continue to grow very rapidly and that it would double every two years. And capacity has actually doubled every 18 months since. Due to Moore’s prediction (postulate), this growth factor became a computer industry popular “law” - “Moore’s Law”.


MORE AMBIENT MIX:       Some music productions are intended to be mixed so as to present the sounds with a great deal of space and ambience, such as live orchestral releases. While all mixes should have good space and dimensionality of their individual and overall sounds, some are a “more ambient mix” than others, such as in the case of recorded live music with an audience, in a large hall, etc., as opposed to a strictly studio recorded music production.


MOS:      Short for slang “Mit Out Sound” (without sound), or “Minus (without) Optical Sound” (an early method for recording sound on films). A cine or video shot taken with no sound recorded.


MOSES AND MITCHELL (PATCHBAY):   A high quality brand of patchbay


MOSFET:       One type of transistor used in high quality audio amplifiers that power loudspeakers. Acronym for Metal Oxide Silicon Field Effect Transistor.

For technical information, read on… MOSFET’s run cooler than normal bipolar transistors, and have faster switching speeds and higher slew rates. High-quality transistors that, when used in an amplifier, deliver high peak current with a shorter signal path and faster response time. This results in enhanced, more clearly defined audio, especially during louder music passages.




MOTION ADAPTIVE TECHNOLOGIES:  In video, especially DVD players this is a technology which works to smooth and sharpen images, especially those which move on the screen. Motion of the image is one of the toughest aspects of DVD picture duplication and Motion Adaptive Technologies helps with this.


MOTION ARTEFACTS:       In video, and very much in DVD-Video playback as well, the term “motion artefacts” deals with distortions seen in a TV Video screen or video projector’s pictures where, when an object on screen moves, it seems to jerk slightly and-or its clarity lessens. This can be due to several factors. For more technical information, read on…More often it is due to an interlaced picture or poor line doubling or poor progressive scan conversion from interlaced. (See PROGRESSIVE SCANNING for full information and definitions for all the words used in this definition.)


MOTION JPEG:    JPEG is an acronym for Joint Photography Experts Group. Motion JPEG is a method of storing, sending and manipulating moving video images with a computer and is commonly used in the AVID Editing computer.

For more technical information on Motion JPEG and the difference between MPEG and Motion JPEG, read on… “JPEG” was developed by a committee of technical people who “jointly” got together and worked out this form of digital processing for images. There is a type of JPEG for processing still photographs by computer - it is just called “JPEG”. ”Motion JPEG” is for video images (and film images transferred to video) which must be converted to digital information in order to be accepted by computers designed to edit and manipulate such images. IMPORTANT NOTE:   “Motion JPEG” is not the same as “MPEG”. MPEG is a similar process to Motion JPEG but mainly used to enable video images to be put on the Internet, onto a DVD disc, broadcast, etc. when no editing or similar manipulations of the pictures are required. When such images require editing, Motion JPEG is commonly used. (More recently, a version of MPEG2 has been developed which fully facilitates editing.) TECHNICAL NOTE: Originally, MPEG2 gave only limited editing capability because it was comprised of several different types of video frames, and only one of those actually has all the video information required when editing. However, MPEG2 now fully supports video editing, with a version that operates using only the video frames with the full synchronisation needed for editing. In order to do proper computerised video editing, it is necessary to have the synch information on any frame chosen to edit (cut and splice). Earlier versions of MPEG only have 1 out of a group of video frames with video synch, so the Editor could not edit on every video frame (he could only ever edit on the one frame out of the group). On the other hand, Motion JPEG solves this problem by supplying synch information for all video frames. Therefore, any video frame desired can be edited upon. In other words, Motion JPEG and the more recent MPEG2 version allow the video pictures to be cut at any point (frame) correctly and to flow smoothly one to the next. (See NON-LINEAR EDITING, AVID.) Note:  Motion JPEG is not a perfect motion picture format in that its images do not always move fluidly on the screen, but it is a workable format for editing. The newer version of MPEG2 is designed specifically to facilitate editing as well as have smooth motion. Read on for the technical specifications on Motion JPEG compression… JPEG hardware and software allow setting the desired compression, from 24-bit lossless (usually 2:1) to lossy compression rates (up to 60:1 in some cases). The various levels of compression allow users to choose how much retention of detail and precision of the original can be done when trying to fit picture information into a limited amount of digital storage capacity.




MOVING PICTURE EXPERTS GROUP (MPEG):   This is a group of technical experts within the ISO (International Standards Organisation). They set technical specifications and standards for the video, audio and film industries which are then agreed upon stable data internationally for the manufacturing, production, distribution and usage of such products. (To obtain PT information on MPEG, see, MPEG’s Internet site.)


MOVING THE REARS TO THE SIDE:      The normal position for “rear surround” loudspeakers (“rears”) in Dolby and DTS film surround sound systems is along the side wall. But some music release mixes done in these formats are mixed to have the surround speakers actually to the rear of the listener. Mixers, as well as consumers, will often have their surround loudspeakers on stands and move them - or opt to just keep them in one position. (See STANDS.)


MPAA:    Motion Picture Association of America. This is the primary agency involved with video content protection for the film industry for both video tape releases and DVD releases. They do other work as well. The DVD Copy Control Association (DVD CCA) is backed by the MPAA. The MPAA can be reached at “”. (See DVD CCA.)


MPEG:    Abbreviation for Motion Picture Experts Group. Committee created with the intent to standardise video and audio for CD’s. In 1992, the International Organisation for Standardisation (ISO) and the International Electrotechnical Commission (IEC) adopted the standard known as MPEG-1. Audio and video encoded by this method could be squeezed down to fit the limited data rate of the single-speed CD format. MPEG-1 is commonly used for video and audio on personal computers and over the Internet. The MP3 format is a nickname for MPEG-1 Layer III audio. The MPEG committee extended and approved its system to handle high quality audio-video at higher data rates. MPEG-2 was adopted as an international standard in 1994 and is used by many new digital video systems. MPEG-2 is also the basis of DVD-Video. DVD-Video is intended for the home video market, where it provides the highest resolution yet from a consumer format.


MPEG AAC:   See ADVANCED AUDIO CODING. It’s the same thing.


MPEG (MPEG and “compression”):      MPEG stands for Moving Picture Experts Group. (See MOVING PICTURE EXPERTS GROUP.) MPEG is a form of digital compression for video AND audio. (See COMPRESSION 3.) MPEG is the most widely used compression format for pictures in the modern audiovisual world. The MPEG process has different quality levels. MPEG also provides surround sound audio, but Dolby and DTS are much more widely used and more available on DVD discs. MPEG is the primary method of compressing picture information for DVD, Internet relay, etc. It also used by DSS (Digital Satellite System) programme providers to transmit high quality TV broadcasts to consumers. MPEG is also used in the new Personal Video Recorders which enable home consumers to record, on hard disc, up to 60 hours of TV programming in a unit the size of a normal home video deck. How is it possible to record 60 hours of TV into a little box??? Such an amount of video information should require tremendous amounts of computer digital power and storage. That’s where MPEG comes in. To understand how MPEG compression works, remember that video, just like a movie film, has individual frames per second. The MPEG process looks at the very first video frame, called an “I FRAME” (INITIAL frame) and records that frame entirely. With the initial frame recorded, the MPEG process then looks at the next frames of the video. MPEG looks at these next frames and can detect what, in comparison to the Initial Frame, has changed in the picture being shot. This all happens very quickly. By determining what has changed in the picture, the MPEG process only needs to keep recording what changed, and NOT what has remained exactly unchanged in comparison to the initial “I-Frame”. To give an example of how all this works, let’s take an ordinary news programme on TV shot by a TV video camera. The newsperson is seated speaking at his desk and there is a world map in the background. Note that the world map never changes in the picture, nor does the desk at which the newsperson is sitting. MPEG compression is “smart”. It says to itself, “Why keep recording those fixed, unchanged images???” To the MPEG process, those unchanged images in the overall shot would just be a waste of digital storage space if they keep being recorded constantly. So, the MPEG process just uses the image of those items already recorded in the Initial Frame. The only changes in the picture, moment to moment, are the motions of the newsperson as he or she speaks. The MPEG process detects the changes in the person’s mouth and records only those. MPEG’s computer programme records, instant by instant, only those portions of the picture that are changing. It does this by assigning the video’s 30 frames per second each a status. It calls the first frame the “Initial-Frame” - (I-FRAME). With the I-FRAME recorded and sent on, MPEG then looks at the next frames that follow and uses one frame to remind itself what the I-FRAME looked like and another frame to determine what is changed in that next instant of time. These other next frames have names. The frame MPEG uses to “remind” itself what the I-Frame looked like is called a “B-Frame” - because it is sort of “looking backwards” at the I-Frame so as to have reference with which to compare the “P-Frame” (“Predictive Frame”). MPEG looks back at the I-Frame and predicts, by comparing the B-Frame to the P-Frame, what actually needs to be recorded in order to capture what changed between the “then” of the Initial frame and the “now” of the Predictive frame. It could not look at the I-Frame itself, as that is already recorded and long gone (in time), so it uses the next frames, one to “represent” (look back on) the I-Frame (the B-Frame) and one to “predict” (the P-Frame) what changes have to be recorded. The MPEG process is always comparing to detect what part of the picture coming from the camera has changed relative to what has not changed and only recording the changes. Of course, many times the changes are so much in the picture that an entire frame must be recorded. Every time that happens, MPEG makes a new “I-Frame”, and uses the following frames as B and P frames to see if it can get by without recording any unchanged portions of the picture just following the I-Frame. In this way, many frames recorded by MPEG aren’t, actually, full new frames. Because the entire picture is not being constantly recorded by MPEG, far less digital power and storage space is required. Things in the picture that don’t change in the shot do not keep being re-recorded - and that is the basis of MPEG “compression”. Fewer recordings are required while still creating the “look” of the TV camera’s picture. Due to MPEG processing, the full news broadcast is seen by the audience, but, unnoticed by them, some of the image was not continuously recorded by MPEG, only repeated. Therefore, less digital information had to travel down wires or over a satellite to the home audience. The newsroom shot is said to be “compressed” - meaning the images of the newsroom are made to fit into less digital capacity. They are “compressed” to fit. MPEG does this same process when a full movie is put on DVD. The DVD disc can’t hold an entire film, much less the entire film’s surround sound audio. If the film was not first compressed, the DVD would only hold about 15 minutes of the movie’s length! Because the film is compressed, its full hour and a half or more can fit. There are ways to adjust MPEG so more information is actually being newly recorded and different ways that MPEG deals with the frames, but the above description is a general concept of how MPEG does its processing. NOTE:     MPEG is used for video DVD’s.


For technical specifications on the MPEG processes, full data can be obtained at, the home page of the Moving Pictures Experts Group. Some technical data is provided below for those who require fast reference to such…


The MPEG1 standard streams video and sound data at 150 kilobytes per second--the same rate as a single-speed CD-ROM drive - which it manages by taking key frames of video and recording only the areas that change between the frames. Unfortunately, MPEG1 produces low quality video, far below that of standard TV. MPEG2 compression improves things dramatically. Modern video delivery media, such as digital satellite services and DVD, use MPEG2. MPEG is a lossy compression method. MPEG files can be decoded by special hardware or by software. The MPEG1 standard provides a video resolution of 352-by-240 at 30 frames per second (fps). This produces video quality below the quality of conventional VHS videos. MPEG2 offers resolutions of 720x480 and 1080x720 at 60 fps, with digital audio. This is sufficient for all the major TV standards, including NTSC and even HDTV. MPEG2 will process the Sony-Philips-Panavision 24p video footage into compressed 24p storage on a DVD disc. MPEG-2 is used by DVD-ROM’s. MPEG2 can compress a 2 hour video into a few Gigabytes. While decompressing, an MPEG2 data stream requires only modest computing power. Encoding video in MPEG2 format requires significantly more processing power. Note that there is also a version of MPEG2 that does not use B and P frames, but records only I-Frames. This solves a problem in editing with MPEG2 compression, as proper video editing requires all the synch information any time a cut is made - and only the I-Frames contain this synch information. This version is now being used in non-linear editing systems and is replacing Motion JPEG as the non-linear editing video format. (See NON-LINEAR EDITING, MOTION JPEG.) The audio in MPEG is a digital multi-channel audio format, which uses a source PCM stream and compresses it at a sample rate of 48 kHz, sample size 16 bits. DVD supports MPEG1 and MPEG2 audio formats, and can have up to 7.1 surround-sound channels. The ISO standards body has now developed MPEG4 (there is no MPEG3 - see MP3). MPEG4 is based on the QuickTime file format. (See QUICKTIME.)




MPEG50:       MPEG50 is the part of the MPEG2 standard that designates the level of MPEG2 compression for Digital Television (DTV) broadcasting at both non High Definition and HD rates. (See HDTV RATES.) MPEG50 processes the digital video signal with far more computer power and has considerably higher quality than the MPEG2 compression used for DVD-Video releases.

For more technical information, read on... The “MPEG50” version of MPEG2 operates at a data rate of 50 Mbps (Megabits per second), which meets the quality standards for DTV, including a compressed form of High Definition. To give a comparison of the data rates, DVD videos record at 9.2 Mbps (6.1 for audio and 3.1 for video) and an uncompressed HD video signal requires upwards of 700 Mbps. This is quite a difference in processing speeds, but the DTV standard (MPEG50) can be used to produce both Standard Definition and High Definition Digital TV programmes. (More information at SDTV, MPEG AND COMPRESSION FOR DVD’s.)


MPEG4, MPEG-4: MPEG4 is for video programmes, but is a recent version of MPEG. It allows a TV broadcast studio to send individual elements of a given scene and those individual elements may be combined later to create the full scene. For example, one part of the scene might be a newscaster and the other part of the scene might be a “virtual set” (a computer generated backdrop and-or set). These and other elements could be separately sent using the MPEG 4 process and later recombined.

For more technical data, read on… MPEG4 supports either compressed or uncompressed video, and can carry metadata. The MPEG4 format is planned to become a standard that allows for time-based delivery of multi-layered, multimedia elements. It will hold over 100 different media types, from Flash files to HTML. Like MPEG2, it is a variable bit rate process. (See VARIABLE BIT RATE.)


MPEG LA:      MPEG Licensing Authority. This is a group formed to collect royalties for intellectual properties processed and distributed using MPEG, especially MPEG 7 and MPEG 21.


MPEG LAYERS:    MPEG Stands for Moving Picture Experts Group. (MOVING PICTURE EXPERTS GROUP is defined as its own entry.) When the first MPEG specifications for audio were defined by the MPEG committee there were two companies trying to develop the technology and they were vying to have their versions become the standard for the audio industry. Listening tests produced no winner, so the MPEG committee decided to create three options, which became known as Layers 1, 2, and 3. They ultimately became known as MP1, MP2, and MP3. Note:    MP1, MP2 and MP3 are audio only and not the same as MPEG1 and MPEG2, which are both video and audio compression methods.






MPEG1:  The earliest and first form of digital compression for TV video pictures and its audio. Thus the “1” delineation. (See MPEG.) It compresses much of the picture information seen over the Internet or on video teleconferences, and their audio. Its picture quality is a bit less that of home consumer VHS videocassettes. It is commonly used for Video CD (game videos). It is the lowest quality form of MPEG compression for video.


MPEG 7: (See MPEG AND COMPRESSION FOR DVD’s.) Where the MPEG 2 process seeks to interpret the information of a picture signal and compress it down into less digital information, the MPEG 7 process is in a whole different realm. MPEG 7 is actually a tool for creating, distributing and managing of digital media content. It’s MPEG’s bid to take the leading control of the digital audiovisual industry. Per Leonardo Chiariglione, the man responsible for representing and conveying MPEG, “MPEG 7 is an audiovisual information representation that is different from the previous MPEG standards in the sense that what is represented is not the information itself but the information about the information”. In other words, MPEG 7 is software to access, create, distribute and manage digital media content - which of course uses the other MPEG types to compress such information. MPEG 7 provides a “toolkit” for searching digital media content. This may be as simple as searching text files for key word matches or as complex as searching vast content libraries for sounds or images with similar characteristics. For example, “find women in blue dresses”, “find sunrises”. Ultimately, each image stored in the MPEG database will contain metadata that will allow the MPEG 7 process to access it and use it to create the images it seeks to create. (See METADATA.)


MPEG SURROUND or MPEG MULTICHANNEL:    (See MPEG.) MPEG surround sound is similar to Dolby and DTS’s surround, but not commonly used when viewing film DVD’s. It is used more for TV broadcasts and video work, while Dolby and DTS have the film DVD-Video market as regards sound.

For more technical information, read on… The audio in MPEG is a digital multi-channel audio format, which uses a source PCM stream and compresses it at a sample rate of 48 kHz, sample size 16 bits. DVD supports MPEG1 and MPEG2 audio formats, and can have up to 7.1 surround-sound channels.


MPEG 21:      (See MPEG 7.) MPEG 21 is a continuation of the MPEG 7 concept and process that will allow anyone with the correct computerised equipment to access any image contained in an MPEG database. It describes the ultimate goal of MPEG to create a database that will supply the video images for any medium.


MPEG2:  (See MPEG for description of how MPEG2 works.) This is the second version of MPEG for video and thus the “2” delineation. It is used for compressing video (films) and their audio for DVD as well as for broadcast applications. Note that a high quality version of MPEG2 called MPEG2 MAIN LEVEL is used to process the picture information on DVD discs, keeping the pictures progressive. MPEG2 will do 5.1 surround sound as well as video pictures. MPEG2 offers resolutions of 720x480 and 1080x720 at up to 60 fps, with digital audio. This is sufficient for all the major TV standards, including NTSC and even HDTV. MPEG2 will process Sony-Panavision and Philips video footage into compressed 24p storage on a DVD disc. MPEG-2 is used by DVD-ROMs. MPEG2 can compress a 2 hour video into a few Gigabytes. While decompressing, an MPEG2 data stream requires only modest computing power. Encoding video in MPEG2 format requires significantly more processing power. MPEG2 is different than MP2, which is strictly an audio format, and is defined separately.


MPEG2 MAIN LEVEL: Abbreviated ML. The highest quality MPEG 2 for video pictures. It is a progressive scanning format, and applies the least amount of compression to the video signal. The higher quality DVD discs and players use MPEG MAIN LEVEL. It means that the video images are stored on the disc in progressive scan format. For technical information, read on…MPEG 2 Main Level uses a type of video compression in which for every 4 samples of the luminance (black and white) signal taken, 2 samples of each of the two chrominance signals are taken (written as 4:2:2). MPEG 2 Main Level refers to the highest quality video compression of the MPEG 2 format. Note that MPEG 2 Main Level, does not have two video fields per frame. MPEG-2, offers resolutions of 720x480 and 1080x720 at up to 60 fps, with digital audio. This is sufficient for all the major TV standards, including NTSC and even HDTV. MPEG2 will process Sony-Panavision and Philips 24p video footage into compressed 24p storage on a DVD disc. MPEG-2 is used by DVD-ROMs. It can compress a 2 hour video into a few Gigabytes. While decoding, an MPEG2 data stream requires only modest computing power. Encoding video in the MPEG2 format requires significantly more processing power.


MP1:      MPEG2 Layer-1 Audio. This is a type of digital audio compression and is the highest quality version of MPEG compression for audio. (Not to be confused with MPEG1.) MP1 is intended for use when directly recording and compressing in “real time”.


MP2:      MPEG2 Layer-2 Audio. This is one of the main MPEG audio formats of compression. It is used for the audio with Digital TV broadcasts. It is used to put audio on some DVD’s (mainly overseas), but not to be confused with the audio put on DVD-Video by Dolby and DTS processes, or how DVD-Audio discs are made. In Asia, MP2 is used heavily on “Video CDs” (CDs that have video games on them.)


MP3:      This is the 3rd type of digital audio processing which is done per standards set by the “Moving Pictures Expert Group” - a technical industry group that defines the standards and techniques for dealing with digital audio and picture content. The MP3 processing is the most widely known for putting music and other audio programmes onto computerised networks such as the Internet. MP3 actually “compresses” the audio down in “digital size”, meaning it processes the sound digitally so that a given audio programme can be stored in less computer space or be more economically transmitted or relayed to other computer users. MP3 can get hours of audio programme stored in very little computer memory space. Consumers can do MP3 CD recordings, at home, of music they wish to listen to either from the Internet or from their CD collections. An example of MP3’s use at Gold is that LRH lectures are sent to the TU EU on an MP3 file via the Internet. These MP3 files are then used for translation purposes - where it is only important that all of the words can be clearly heard and the sound quality is not otherwise critical.

For more technical information on MP3, read on… Stands for “MPEG Layer-3 Audio”. (See MPEG LAYERS for the definition of “layers” in this usage, as well as what the “3” stands for.) This is the main MPEG audio format of compression. It is used for things such as putting music on and taking it off the Internet (streaming). CD players are now available that play MP3 homemade CDs as well as conventional CDs, plus there are many little MP3 players which store music in memory. MP3 car audio products are available as well. It is not a high quality sound compression format and sometimes falsely billed as being a “lossless” compression. (It uses auditory masking - perceptual coding and compresses 11 to 1.) MP3 uses a codec (compression in recording, decompression on playback process) called “sub-band coding”. (CODEC is also defined separately.) The MP3 codec separates the audio signal into bands before coding it. Because each band has less bandwidth than the total, it can be sent with a lower sampling rate than the original total, although the total sample rate still comes out the same. However, some of the distortion and noise artefacts are filtered out during the reconstruction of the signal thus hiding the fact that fewer bits were used to encode each sample. MP3, in addition to sub-band coding, also uses “auditory masking”. (See AUDITORY MASKING.)


MP3 CD’s:     A recordable CD used mainly to record music directly off the Internet. Also the CD player itself. Most such players will play both conventional CDs and MP3 CDs. Note that MP3, due to the amount of compression used in its process, is lower in quality than a standard compact disc. (See MP3.)     (See INTERNET MUSIC.)




MP4:      MP4 is one of the latest MPEG compression formats which can be used for Internet transfer and downloading of music and video information. (A programme available on the Internet called “DivX” uses MP4 compression to transfer and download DVD video and other video footage.) MP4 is also the type of compression Dolby is using in their “Advanced Audio Coding”, which is a copy protection code being adopted by the industry to be applied to all music on the Internet. It allows one to download songs from the Internet, but that downloaded song cannot be copied digitally by the home consumer due to protection coding installed with the MP4 by Dolby. There are several other types of compression developed specifically for the Internet. MP3 is only one type. Others are AAC, as mentioned above, and Digital Rights Management (used in Microsoft’s Windows Media Audio - WMA.)


MOTORBOATING:      A sound which literally sounds like a motorboat’s engine rapidly fluttering and chugging in a rhythmic way - it’s a low bass (low-frequency) vibrating sometimes heard in audiovisual equipment. For example, this can be heard in video cassette recorders if the tape is not aligned properly on the head of the player - called mistracking.


MOTU (“MARK OF THE UNICORN”):     Brand name of a company that specialises in making digital audio equipment.




MOVING COIL (MC): A type of phonograph record cartridge for playing records. It’s the small part that attaches to the record player’s tonearm and has the small diamond needle which tracks the grooves in the record. These are considered the best sounding of all phonograph cartridge types. A moving coil cartridge is one in which the magnets are stationary and the coils where the signal is generated move in response to the motions of the stylus in the record groove. Most MC cartridges produce very little current, and their output must be amplified to standard levels by a "head amp" or pre-preamplifier before further processing by a phono-preamplifier section.


MOVING COIL MICROPHONE:       A term used with the same meaning as the term “Dynamic Microphone” (a microphone in which the diaphragm moves a coil suspended in a magnetic field to generate an output voltage proportional to the sound pressure level.


MOVING MAGNET (MM) CARTRIDGE:  The most common type of phonograph cartridge for playing records. It’s the small part that attaches to the record player’s tonearm and has the tiny diamond needle which tracks the grooves in the record. The magnets are so attached that the motion of the tonearm and stylus causes the magnets to move near coils of wire, generating an electric current representing the audio signal. (Compare MOVING COIL.)


M.P.S.E.:       Abbreviation for Motion Picture Sound Editors. A Los Angles based honorary organisation of film and television sound editors founded in 1965. Every spring the M.P.S.E. gives out its Golden Reel awards at its annual banquet.


MPX (multiplex):       1) A method of combining two or more signals into one. 2) Some cassette tape decks have an “MPX filter” that removes the 19,000 Hz “pilot tone” from stereo FM broadcasts. (See MPX filter for more information.) (See PILOT TONE.)


MPX FILTER OFF, ON BUTTON:      MPX stands for “multiplex”. “Multi” means “many” and “plex” means “to combine parts”. So the word means “to combine many parts”. Often consumers who purchase cassette decks record music and programmes off the radio. However, there is a problem when doing so. Radio is broadcast using very high frequency carrier waves, and cassette decks also use high frequency waves to help them record. So, when recoding something off the radio, it is best to get rid of the radio station’s carrier wave or the recording quality will suffer. The MPX FILTER is there to get rid of the carrier waves that radios use. It filters (gets rid of) these waves without harming the music the radio is playing because the carrier wave is higher in frequency than most music. For more information, read on...The reason the button is called “MULTIPLEX” (MPX) is because radio stations (and TV stations too) can use their carrier wave to broadcast more than one signal at a time (“multiple” signals). For example, FM radio is usually stereo (2 channels), which means that there are two separate audio signals. So, when FM radio stations broadcast in stereo, it is a “multiplex” broadcast. Multiplexing adds an additional high frequency wave to the carrier wave. This additional wave is used to separate the left channel from the right channel. In FM radio broadcasts, this high frequency wave is at 19,000 cycles per second, which is at the upper range of human hearing and can be heard with high quality audio equipment. It would also interfere with the cassette recorder’s electronics as mentioned above. The MPX Filter removes that frequency and prevents it from being heard and-or interfering with the cassette recording. So, just per the derivation of the word “multiplex” given above, the “MPX FILTER” gets rid of these various waves and lets the cassette deck record the music off the radio.


MRL:      Abbreviation for Magnetic Reference Laboratories. A company that has recording equipment of verified accuracy that manufactures test tapes. This company produces the calibration tapes used in Gold’s audio studios.


MSB:      (Most Significant Bit). The bit within a digital word which represents the biggest possible single-bit value. For example, in the digital word, 1100101100110101, the 1 on the far left is the most significant bit. (Compare LSB.)


MS DECODER:     This is a term used in the SADiE digital audio computer manual. MS is an abbreviation for “Middle-Side” which is a microphone technique used for stereo recording. An “MS” recording is done to create a very natural and lifelike sound, which has excellent presence and dimension. As a technique, MS recording is more versatile (able to be manipulated in mixing to create an effect of presence and space in the sound). Two microphones or a single stereo microphone having two separate pickup elements are used:     One is the type that picks up in only one direction and is pointed toward the middle (directly at) what is being recorded. The other is a type that picks up in two directions. That second microphone is not aimed directly at the sound source, but off to its side, 90 degrees away to the left and right. The mic’s are set up as closely as possible to each other - in such a way that their sound pick-up patterns are perpendicular. (A stereo microphone with rotatable sound pick-up capsules such as the Schoeps 501 is ideal for MS recording.) The two microphones are recorded onto two channels as a left and right stereo pair, but they are intended to be played back not as a simple left and right, but as follows:      Middle microphone plus side microphone in-phase for the left channel and middle microphone plus side microphone out-of-phase for the right channel. A basic technique for doing this is to put the “side” microphone recording onto two separate channels of the mixboard and the “middle” microphone on one. The Mixer then reverses the phase of one of the channels (using a phase switch on that mixboard channel) and combines it with the “middle” microphone recording by panning the middle mic to the centre and the out of phase mic to the right. He then takes the second side microphone channel (the in-phase one) and pans that to the left - thus also combining it with the middle mic which is panned to centre. Many combinations of the panning can be done to achieve different presence and spatial effects. The SADiE audio system has a built-in process for playing back an MS recording, called an MS Decoder. This decoder takes the sound recorded using the MS microphone(s) and processes the sound automatically as described above.


MS Micing:    See MS Decoder above for definition.


MSO:      Multiple System Operators. These are companies that supply multiple systems to consumers, such as Cable Digital TV, Internet access, Internet Telephone, Interactive TV, etc. all together as bundled services. AOL Time Warner is a Multiple System Operator.


MSP-1:   Abbreviation for Master Stereo Preamplifier Version 1. This is a very high quality preamplifier designed and built at Gold for use in studio audio recording, routing, and switching. It is on virtually all sound lines at Gold. Commonly referred to as just “the MSP.” It is most often used to control volume and can switch rapidly between different sources of audio to compare sound quality and volume levels.


MSP 1M:        Abbreviation for Master Stereo Preamplifier Version 1 Monitor. This is a version of the MSP-1. (See MSP-1.) The MSP-1M was designed and built specifically for use in listening to high quality loudspeakers and headphones and switching between different sets of these and to feed them different sources of audio very rapidly.


MSTV:    Abbreviation for Association for Maximum Service Television. This is an American association dedicated to higher quality TV service to consumers. It is involved in setting standards for High Definition and Digital TV for consumers and it works closely with the National Association of Broadcasters (NAB).


.MSU:     .MSU stands for “Mixer Set-Up.” This is a specialised type of computer file for the SADiE and its use is covered in the SADiE manual, but its exact definition is not, so it is given here.


MTA:      See Connectors Types Of.


MTS:       Abbreviation for Multichannel Television Sound. It is sometimes announced or printed in regards to TV broadcasts which have some form of surround sound.


M2 Gauss:    See Cetec-Gauss. .


Muddy:  A derogatory audio term meaning ill defined, not clear. Lacking high treble frequencies so sounds dull.


Muffled: Very dull-sounding; having no apparent high frequencies at all. The programme sounds as if it’s covered with a blanket. Weak highs or weak upper mids. The result of a severe loss of treble frequencies from about 2 kHz on up.


MULTI-BRAND REMOTE:  A remote that is designed to be able to control several different brands of A.V. equipment from a single remote control.


MULTICASTING: A method of transmitting computer audiovisual information that allows multiple users or systems to use the same stream (or channel).


MULTICHANNEL ANALOGUE (inputs or outputs):    1) The 6 channel outputs on a DVD-Audio player which allow hook up to an audio system using 6 discrete (separate) channels not via the Dolby or DTS film surround inputs of an Audio Video Receiver, Digital Controller or multi-channel audio pre-amplifier. 2) The fact that any piece of audio equipment has the capability of playing multi-channel surround sound without going through a Dolby or DTS film surround setting, but rather bypassing any such settings entirely and going directly to amplification and then to loudspeakers.





1) Said of any event presentation or consumer entertainment that involves many different types of media such as sound, lighting, picture display, laser shows, graphics, etc. all combined.

2) Video games are sometimes referred to as “multimedia”.

3) A consumer’s home entertainment system can be referred to as a “multimedia centre”. 4) Large professional film and video studios who deal with all formats, sound, pictures, etc. often call themselves, “multimedia studios”.




MULTIMEDIA CARD:  A very small digital storage device (a card), which is used in some MP3 players. (See MEMORY STORAGE DEVICES for full listing.)


MULTIMEDIA PC MARKETING COUNCIL:    The group that sets specifications and guidelines for the production of multimedia discs. (See MULTIMEDIA.)


MULTIPATH: A condition that occurs when a broadcast radio or TV signal reaches the antenna over two or more paths of different lengths. The result is an interference that causes distortion and a loss of stereo channel separation. Such a situation can easily occur and often does, especially in cities where the broadcast waves reflect off large buildings, in addition to being received directly from the TV station itself. Therefore, more than one wave is being received. The two waves are out of time compared to each other as one is a reflection, or an “echo” of the direct wave. This can cause “ghosts” in the picture received (double images on the screen.)


MULTIPLE STREAM DECODER (RECEIVER):       This is a feature Digital TV (DTV) receivers have for consumers. Using a multiple stream decoder, one can receive multiple streams of DTV programmes enabling you to watch a given programme on TV, but at the same time be recording another programme. More than one programme is being received at the same time, thus the receiver is called a “multiple stream receiver”.




MULTIPLEX: To combine or transmit several signal or data streams on the same circuit or channel.


MULTIPLEXER (MUX):      Device for combining two or more electrical signals into a single, composite signal.




MULTI-ROOM, MULTI-ROOM SYSTEM: 1) The type of audio equipment that is designed to send music, etc. to more than one room and to be able to control each room’s sound individually.

2) A piece of equipment can be multi-room or an entire system can be a “multi-room system”.


MULTISESSION or MULTISESSION DISC:   Usually a recordable CD must be recorded to all at one time, meaning you record to the disc once and then that’s it. There may be room for more information to be recorded, but once you stop the initial recording process, the disc will not accept any further information. This is called a “closed session” disc. However, there are “multisession discs”. These allow a recording to be made to a disc during one “session” (one finite period of time) and then additional recordings to be made in later sessions. Some types of recordable compact discs can require more than one recording “session” to create their contents. For example, a CD that has music plus graphics, text and still photos usually has these different types of data recorded during separate sessions. The music may be recorded first, and in subsequent sessions the text, graphics and pictures are added onto the recordable CD. Also, some CD burners a selection as to whether you want to record multisession or closed session on any recordable CD media.


MULTITIMBRAL: Said of a musical synthesiser. When one key of the synthesiser is pressed, more than one sound can be made by just that one key. Combined sounds can therefore be played. Compare to monotimbral, which means the instrument can only make one sound at time when a key is pressed. Also called polytimbral. (Compare POLYPHONIC.)


MULTITRACK:      A professional audio recorder, digital or analogue, that can record many different sounds and play them back. This is done with a separate “track” (area of the tape) for each sound. Usually each track is assigned its own channel on a mixboard which is then used to blend all the sounds together by the Mixer.


MUSHY: Sounds that are mushy are “soft” - meaning they have no impact or punch. They lack presence and don’t sound clear. A mix can sound “mushy” as can loudspeakers, if they lack presence and impact and individual sounds are not clearly present and distinct from other sounds.


MUSIC COMPILATION MASTER:    Recordings of each song or piece for a new music release assembled in proper order. Each separate piece is edited together forming a “Compilation Master”. If the product is intended for cassette release, two reels - one for side A and one for side B of the cassette will be created. Each recording used is taken directly from the mixboard as the final mix is played. The Compilation Master is used to fully prepare final Audio Production Masters for cassette tape release, or, in the case of digital release (CD, DVD, etc.) it is used to create the Plant Master.


MUSIC MAN:        Brand name of a musical instrument and amplifier manufacturer.




MUT:      Acronym for Make-Up Table. See DOUBLE MUT for definition.



1) A term for the stopping of sound heard over loudspeakers or earphones with a button that cuts the sound instantly.

2) It’s an on-off switch that interrupts the signal flow, commonly found in each channel of a mixboard or on audio equipment to rapidly kill all sound.


MUTED: Said of sound when it is dark (lacks high frequencies), lifeless, and lacks any punch or dynamics.


MUTE SWITCH:   See MUTE def #2.


MyDVD: A home consumer personal computer authoring tool produced by Sonic Solutions. MyDVD is used by consumers to create their own DVD programmes. The MyDVD tool is compatible with Windows 98, Windows 2000, Windows Millennium and Windows NT personal computers.


MY-LINK:      Abbreviation Myryad Link. Myryad (not myriad) is a brand name of digital A.V. equipment. “My-Link” is their remote control hook-up that uses a pair of RCA connectors installed in Myryad A.V. equipment to send commands to it. This brand of remote can be used with this specific brand of equipment and can have cable lengths of up to 250 feet. Thus, many different Myryad brand units, or equipment made by other manufacturers which accepts such wiring and connections, can be remote controlled in many different rooms throughout a house or building. There is no audio sent over the controlling wires, just a remote control code called “RC-5”.