Audio-Visual Glossary



LACQUER:     When making a phonograph record, the lacquer is the soft disc cut on a lathe from the master tape. It is the first disc stage in the production of LPs. From the lacquer are made a number of negatives and positives before the negative metal stamper can be created to press vinyl discs. It is a blank recording disc that has an aluminium inner disc coated with lacquer, and where grooves moving according to the audio vibrations have been cut into it by a disc recording machine. The “lacquer” can be duplicated in phonograph record manufacturing. Such records are still being made today and are popular amongst audiophile listeners.


LAeq:      (LAeq is a technical term that specifically deals with audio volume levels for Digital Television [DTV] broadcasts. To gain a full understanding of the term, first see LEVEL, DIALNORM, WEIGHTING and FSD in this glossary.) LAeq is an abbreviation for Level, A Weighting equivalent. It is a method of measuring the apparent loudness of the audio for a television program and assigning it a number relative to Full Scale Digital (FSD). The LAeq number is the equivalent of the average loudness level, using A Weighting, of the audio content of a Digital TV program. The television receiver in the consumer’s home processes an assigned Dialnorm LAeq number to adjust the playback level of the audio portion for each broadcasted TV program. It is now a requirement set by the FCC (Federal Communications Commission) that digital television (DTV) broadcasts have Dialnorm incorporated into their audio programs. The Dialnorm LAeq number is determined by averaging all the moment-by-moment audio volume levels over the length of the entire program and assigning that one average number as the LAeq


LAG AND LAG-FREE:  The terms “lag” and “lag-free” refer to digital audio work stations and other digital audio equipment which have (or do not have) a lag between when a sound is recorded or mixed, and hearing it over loudspeakers or headphones. Some of this type of equipment literally has a lag to the sound so if you do something to a sound in the computer you can’t hear it for a fraction of a second. When recording, this can be particularly bothersome as one would like to hear the sound the instant he plays the notes. Specification sheets and promotional write-ups on such equipment will usually state if there is a lag to the sound or not.


LAID BACK:  1) Recessed and distant-sounding, having exaggerated depth with no presence. Midrange frequencies are lacking. The sounds are not much “there”. 2) The term “laid back” also describes a skill that many musicians and singers use when performing. They intentionally (or naturally) don’t sing or play directly in time with the beat of the music. Rather, they play ever so slightly behind the beat. This is called “laying back” or “to lay it back”.  Blues artists are masters at this. It gives real “feel” to the music and lots of emotion. 3) When a video is completed and the final audio mix is transferred from the studio’s mixboard directly to the master videotape, the process is called “layback”.


LAMBDA:       Brand name of a company that makes high-quality power supplies for audiovisual equipment.


LAMP:    Any device consisting of a light bulb and its housing used to produce light. It is distinct from a “bulb” in that a lamp includes the housing or mounting for the light bulb. For example, in a film projector there is a “bulb” that sits in the lamp housing. Video projectors also have lamps.


LAMP CURRENT: The amount of electricity that flows through a film projector lamp to get it illuminated to a specified luminance. This can usually be adjusted on professional film projectors.


LAMP HOUSE:      That assembly on a film projector which houses the projection lamp for the projector.


LAN:       Abbreviation for Local Area Network. A group of computers, terminals, workstations, printers, etc. that are connected so they can share information. LANs are commonly used within a company, an audiovisual studio, etc. between offices so that computer facilities can be shared. With a LAN, a big central computer can serve many terminals in different locations, or many separate computer terminals can simply be connected up to share information, printers, etc. LANs are usually connected with wire, but there are also wireless networks available that can extend the interconnection of a LAN way beyond a single building. With the use of communications satellites, this interconnection can be extended across town, across a country or even around the world. Some satellite companies such as EchoStar specialise in this.


L & R:    The Left and Right loudspeakers in a stereo audio system or the front Left and Right loudspeakers in a surround sound audio system.


LANDS:  During the recording of a glass master disc for CD and DVD replication, a blue argon laser beam burns pits in a spiral track on the specially prepared recording surface. The “lands” are the flat spaces between those pits.


LAPPING:     To resurface (polish) a tape recorder’s worn heads so they perform at manufacturer’s specs. The process is called “lapping”.


LARES:   An abbreviation for Lexicon Acoustic Reinforcement and Enhancement System. (See AUDITORIUM SYNTHESIS for full definition.)


LASER:   Acronym for light amplification (by) stimulated emission (of) radiation. every cd player and dvd player has a laser light beam inside that tracks small pits which exist inside a cd or dvd disc.




LASER DISC:        Pioneer’s trademark for a laser-read videodisc system. This is a video format no longer in use as it has been superseded by the DVD.


LAST MILE:   The term, “last mile” refers to the distance between the cable TV company’s main cable lines installed to carry its signals and the home consumers or businesses that desire the cable TV service. For example, if a Hollywood, California customer was located on the corner of Hollywood Boulevard and Ivar and the cable company had lines already installed up to Hollywood and Vine, the “last mile” would be only one city block long. But if a customer lived in a rural area where the nearest cable TV line was 10 miles away, that “last mile” would really be 10 miles long (and probably not a viable installation for the cable company).  If the “last mile” is too long for the cable provider to viably provide service, home consumers usually subscribe to a satellite provider or just use an antenna to pick up their local TV stations. (Note:      The term “last mile” is also used by telephone companies in getting phone service to your door from their main wires and cables at the street.)


LATENCY:     How long an audio or video signal is delayed going through a unit performing some process on the signal. For example, some digital audio processing equipment delays the signal briefly so one actually hears what you did to the sound later on the loudspeakers. Also, when digital compression is applied to a signal, such as MPEG, there is a slight latency - it is not an instantaneous process.


LATERAL TONE ARM: On some phonograph players, the arm moves across the LP record always staying perfectly lateral to the record surface. Also called a “straight line tracking arm”. (A tonearm is the slender bar on a phonograph player to which the diamond tipped cartridge is attached - the arm allows the cartridge to track across the record’s surface, following the record’s grooves.) A lateral tone arm is as opposed to conventional arms, which have a pivot point and so travel at an angle across the record’s surface. Both types of arms are still made today.


LATHE:   A machine that forms a master phonograph record for duplication. It cuts the grooves that make the sound so it’s called a lathe .


LATITUDE:    This term is often used when referring to the capability of film or video to record and display a wide range of image brightness from very bright to very dark. “Latitude” comes from the Latin word meaning, “breadth”. Professional photographic film - both still and motion picture - is well known for its capability of producing very bright images, very dark shadows and all brightness in between. It can reveal very subtle differences in the shadowed areas and well-lit areas of a scene and to that degree it very much replicates what is seen in the physical universe. Video, as a medium, generally does not replicate this range and nuance of brightness with the same latitude as film. This is one of the reasons filmmakers are reluctant to drop the medium of film for creating their products. However, recent technology in the area of High Definition video has greatly increased the latitude of the video medium so that it is very much like film in its capacity to record and display a very wide latitude of image brightness.







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, which will be passed over for mass duplication.


LAYERED COMMERCIALS:        Commercials on Digital TV and the Internet that are interactive. The viewer can interact with the commercial by selecting to go to different “layers” of information available about the product or service being advertised.


LAYERED CONTROL (LAYERS):      On many computerised controls, one control (button or knob) can perform many different functions depending upon how it is assigned or the status or setting of other controls. Each different control function is called a “layer”.


LAYERING:   1) In the field of audio reproduction, the reproduction of depth and receding distance, which audibly places the rows of performers one behind the other when listening over loudspeakers. 2) Layering is also done in video editing and special effects where one picture is layered on top of another.


LAYING DOWN TRACKS:  Recording individual sounds onto their own separate portions of audio tape. Each sound has its own track. “Laying down” is slang for recording.


LAYOUT:       As in a mixboard or other audiovisual equipment with its many controls - how they are “laid out”.


LBR:       An abbreviation for Laser Beam Recorder. LBRs are used in glass mastering CD’s and DVD’s. The machine actually creates the glass master which is then further processed to eventually be able to mass replicate the digital discs.


LCD, LCD SCREEN, LCD DISPLAY: (Liquid-Crystal Display). This is one type of screen used to display computer, video, TV images - it is one of the newer types of flat screens which are commonly used with personal computers. Crystal, because its atoms are very orderly arranged, can easily be made to respond to electricity. Some liquids have this crystal-like property and are used for displays in things such as wristwatches, calculators and video screens. LCD screens operate on the principle that crystals bend when they are hit with electricity. A video or computer LCD display has a bright fluorescent light that is placed in the back of an LCD. When the liquid crystal is charged with electricity it bends and thus it also bends the light. This property of the liquid crystal is used in creating the video image which one sees on the screen.


LCR:       (Left, Centre, Right loudspeakers in a surround sound system). There is a specific delineation between the LCR speakers and the surround speakers (which are usually Left Surround and Right Surround). The reason a distinction is made is because OFTEN the surround speakers, not having as critical of music or audio information being played over them as the front LCR speakers, will be processed differently than the LCR speakers, i.e. with less digital processing power. For example, it is not uncommon for a DVD to be produced in such a way that the Left, Centre and Right speakers receive the bulk of the digital power - meaning the sounds recorded at a higher rate than the sounds coming from the surround sound speakers. This is done to help get the maximum digital storage on the DVD disc and to apply the most processing power to the sounds that matter most - those in front of the listener where the main bulk of the music is or, in the case of a film, where the dialog and most of the music and sound effects are. Dolby and DTS film surround electronics do this trick when the audio is converted into their systems at the film studio and upon playback in the theatre or home. For a DVD-Audio disc, a similar trick is done if there is not enough storage capacity on the disc. The rear surround speakers may have lower bit and sampling rates than the front speakers. 


LCRS:     Left, Centre, Right, Surround-speakers, an abbreviation used when speaking of surround sound audio systems for music or film playback.


LCRSS:   An abbreviation for Left, Centre, Right, Surround, Surround. LCRSS is used to refer to surround sound mixes and systems that have two separate surround audio channels, as opposed to the types of surround sound having only one channel of audio for all surround loudspeakers. For example:  Dolby, DTS and Sony’s Digital surround sound have two or more separate channels of surround loudspeakers, each receiving its own surround signal information. Earlier surround sound methods, such as Dolby Stereo and Dolby Pro-Logic, only had one channel of surround sound and though more than one loudspeaker would be used out around the audience, they all played the same exact audio information.


LEADER:        A “leader” is additional tape or film that is spliced onto the head and tail of an audio tape or movie film. Film leaders usually have a numerical countdown, starting from 8 and running down to 2. The head leader at the beginning of each film comprises a projector threading section that contains information about the reel’s content, (such as film title, reel number, etc.). The countdown section begins with the “Picture Start” frame, which is considered the “start mark”, followed by a numbered countdown totalling 12 feet (8 seconds). The last number is “2” (seconds) - three feet - before the beginning of the first frame of the picture seen by the audience. In professional theatres, the leader is never shown to the audience. The projectionist keeps the film projector’s light blocked until the leader passes through.


LEAD-IN:      The very beginning of a CD or DVD disc before the actual audio or visual information even starts. It is in this area of the disc (nearest its centre) that contains the discs Table of Contents as digital information on the disc which can be read over a computer screen or some CD players equipped to display such.  The lead-in contains other information for the disc player as well such as the correct playing speed required by the player.


LEAD OFF:    When performing music, often the conductor or one of the band’s members will count, “1, 2, 3, 4” to start the song. This is actually giving the band the timing of the song. It is called “lead off”.


LEAD-OUT:   The last area on a CD or DVD disc, at the end of the program. It tells the CD or DVD player that the program has ended and it can stop its playback.


LEAKAGE:     1) Sounds from other instruments and sources which were not intended to be picked up by the microphone. For example piano sounds picked up by the guitar microphone. 2) Electrical batteries in audiovisual equipment, if not changed regularly, can leak a fluid from inside the battery and cause the equipment damage. 


LEAN:     Slightly bass-shy. The effect of a very slight bass roll-off (reduction) below around 500 Hz.


LEARNING REMOTE: A handheld remote control for home entertainment centres which can be programmed to control all or most of the components. Today, many remote controls supplied with A.V. consumer equipment can “learn” how to also control pieces of equipment not even made by the manufacturer of the supplied remote control. They are called “learning” remotes. Sometimes called “Universal Remote”. 




LECTURE MIX LINE(s):    These are the Gold audio studios built specifically for the restoration and mixing of LRH’s lectures and for mixing the translated versions of LRH lectures. They are located in the Audio Building.


LECTURE PRODUCTION MASTER (PM):      In order to mass duplicate and release a volume of each individual LRH lecture, be they translated or LRH himself speaking, a master tape must be created that can be turned over for such manufacturing. Obviously the mixed master recordings of the lectures can’t be used for mass production copying. Moreover, special equipment is used for such duplication and that equipment requires unique formats of recordings. A special copy line exists just for this purpose creating the CD ROM production masters used in high speed cassette manufacturing.


LED:       Light Emitting Diode, an electronic component which emits light whenever a voltage of an adequate level is applied to it. An electronic readout which produces its own light.


LEFT, the LEFT:   The left loudspeaker, or the left channel sending signal to that loudspeaker.


LEFT SURROUND:      The left loudspeaker that creates the surround sound information in a surround sound music or film presentation.




LENS:     A series of optical elements (pieces of ground glass), contained within a barrel or tube, which collect and focus light. Used in photography of all types as well as for printing film in the Gold Film Lab.


LETTERBOX, LETTER BOX:      Video versions of a film which show the picture size as seen in a movie theatre. This results in a long narrow picture on one’s TV screen with black areas above and below the picture. The long narrow size of the picture looks like a letterbox, and thus the name. There is important information concerning screen picture sizes and the letterbox format at the glossary entries DVD SCREEN SIZES and ASPECT RATIO.

For more technical information, read on… The resulting image width is much greater than its height. On a TV screen with a conventional 4:3 aspect ratio, letterboxed videos appear with horizontal black bars above and below the image. Letterboxed films for DVD can come in two sizes - 1.85:1 and 2.35:1. Note:  A 2.35:1 Letterboxed DVD, when played on a 35 inch TV screen, will shrink severely. Vertical picture height will go down to only 13 inches tall when normally the screen shows a 21 inch tall picture - 38% less picture area.


LEVEL:   The magnitude of a signal, expressed in decibels.


LEXAN PANELS:  Large very thick plastic sheets used in our studios to place around a musician or speaker who is recording voice or a musical instrument. The plastic is perfectly and smoothly curved so sound hitting it reflects back out into the studio very evenly. The principle of Lexan (a brand name) panels is that when an instrument makes music, it creates many different frequencies. All these frequencies combine to make its sound. However, different frequencies exit or emerge or are sent out from the instrument in different directions. Not all the frequencies come off the instrument evenly nor in the same direction. Sometimes the lower bass frequencies may come out the back of the instrument whereas the high treble frequencies come more from the front or the top. To capture as many of the frequencies as possible and to send them BACK in the direction of the microphone, Lexan Panels are used. Though it is reflected sound being sent to the microphone, the panels are so close to the instrument and microphone that the reflections are not easily perceived as reflections. To the contrary, the sound is very natural and full-bodied. As the high frequencies are not allowed to “escape”, the recording is naturally bright and alive so less processing and correction of the recorded sound is required later in the mix. The technique of Lexan Panels is unique to Gold. It allows us to record all sounds in a non-reflective (dead) studio environment so no unwanted room reflections are added to the pure sound of the instrument (or voice). 


LEXICON:     The name of a company that manufactures audio equipment, especially effects gear for mixing. They are most famous for making high quality digital reverberation units which can create all types of echoes, delays and the sound qualities of large halls, auditoriums, etc.


Lexicon Acoustic Reinforcement and Enhancement System (LARES):      (See AUDITORIUM SYNTHESIS for full definition.)


LEXICON LOGIC 7 SURROUND SOUND:      Lexicon is a manufacturer of extremely high quality surround processing equipment. Their better processors have the capability of taking a 5.1 surround sound mix and turning it into 7 channels of surround sound.


LF:  Low frequency(ies).


LFE:        Low Frequency Effects” channel, sometimes referred to as the “Low Frequency Enhancement” channel. When a movie’s surround soundtrack is mixed, there is a special audio channel which is used for all the very low bass sounds such as bombs going off, trains going by, earthquakes, jet engines, etc. This is the LFE channel.




LFO:       Low Frequency Oscillator. This is a term usually associated with synthesisers. Synthesisers use various electronic circuits to change a sound. One starts with one sound and, by sending it through the different parts of the synthesiser’s internal electronics, the sound can be changed by the synthesist (person). One type of circuit built in to a synthesiser to accomplish this is a “low frequency oscillator”. It uses a very low frequency - below human hearing - to modulate (change) a sound signal. One doesn’t hear the low frequency being used to modulate the sound, he or she just hears the change that results. LFO’s are often used to create a “vibrato” sound that can help make synthesised sounds such as a violin more realistic. It does this by approximating the violinist’s fingering of the instrument so as to make a note slightly shift its pitch back and forth - which gives a certain character to the note. 


LIGHTPIPE OUTPUT: This is the cable used to connect up ADAT digital tape recorders. The “lightpipe” is ADAT’s cable that allows 8 channels of input and output of audio signal. (See ADAT.)




LIGHTWORKS:    This is a term found in the SADiE digital audio computer manual. “Lightworks” is the brand name of a computerised digital audio-video editing workstation, not made by SADiE, though the SADiE system will process audio programs that have been produced in a Lightworks DAW.        


LIMITER:      The mixer may use signal processing devices known as compressors and limiters to meet the restrictions of the recording medium. The terms compression and limiting have been in the audio vocabulary for years, yet there is often some confusion over their definitions. The confusion arises from the fact that both the compressor and limiter are devices that restrict the dynamic range of a signal and the difference between them is one of degree, with the limiter having the most effect.

To simply define: 

COMPRESSOR:     An amplifier whose gain decreases as its input level is increased. 

LIMITER:             A compressor whose output level remains constant, regardless of its input level.


Both definitions are valid only after the signal being processed reaches a certain level. Therefore we have one more definition:  

THRESHOLD: The level above which the compressor or limiter begins to function.



1) A transmission line or any signal path.

2) A specific arrangement of audiovisual equipment, with exact written and followed procedures for the operation of that equipment so as to produce an A.V. product.

3) Also called a Production Line. (See PRODUCTION LINE.)




LINEARITY: A measure of the flatness of frequency response of a signal, as an indicator of the accuracy of the signal being reproduced. A general term referring to the accuracy of response of an audio component in terms of a particular measured parameter, such as frequency response.


LINEAR PCM (LPCM):       Linear Pulse Code Modulation. This is a type of digital audio method of processing music and other audio programs. It is the digital method used in the production and playback of CDs, DAT recorders, and other high quality digital audio formats. The process is referred to as “linear” because linear PCM keeps the groups of digital bits in one straight (“linear”) line as opposed to dividing them up into compressed groups. PCM uses a sound’s many increases and decreases in volume (modulations and pulses) to enable a digital recorder to “see” or “track” what the sound is doing moment to moment so as to record it accurately. Linear PCM has no compression applied to the digital signal, meaning it doesn’t reduce the amount of audio data in order to have it fit into a smaller amount of digital storage space. (Compression is defined as a separate entry. See COMPRESSION3.) There are other versions of PCM which are compressed, such as Dolby Digital Surround sound (all types) and DTS digital surround sound (all types).


LINEAR-TRACKING TONEARM:      For some better phonograph record players, a type of tonearm that moves in a straight line across the radius of a record. (Compare LATERAL TONE ARM.)


LINE CORD: A cord that connects the electronic equipment to the 110V or 220 volt wall power. 




LINE DOUBLER, TRIPLER, QUADRUPLER:  Video pictures on a TV screen or projected on a screen are made up of many hundreds of individual lines which make up the picture. You can see these lines if you look closely at TV or projected TV-video image. To improve the look of a TV or video screen, devices which increase their lines of resolution are used. These are called a “line doubler” (doubles the amount of lines on the screen), “line tripler” (triples the number of lines on the screen) or a “line quadrupler” (4x the number of lines on the screen). DVD players and computers that play DVD’s and better quality TVs can sometimes have a built-in line doubler. Often called an “upscaler” or “upconverter”.

For more technical information on line doublers, triplers and quadruplers, read on… Also called a “deinterlacer”, an “upconverter”, or a “scan converter” or upscaler. Line doublers deinterlace interlaced signals converting them to progressive video. Triplers and Quadruplers scale the resulting progressive video to create 1.5 or 2 times the scan lines of a line doubler to reduce their visibility, particularly on large images. In reality a doubler does not actually double the number of lines, but instead combines the two interlaced fields into a single frame, which is then fed to the display and scanned progressively in a single pass. This line-doubling smoothes the picture and makes the line structure far less visible, even though no increase in the total number of lines has actually occurred.


LINE DRIVER:     A specialised type of preamplifier that is used to boost the volume of signals when very long lengths of cable (wire) are involved. The “line” in this case is a cable and the equipment it is connected to and a “driver” is an electronic circuit used to increase the strength (volume) of a signal. An example of the use of a line driver is on the Set Sound Line in the Castle. Because the studio is very large, there are literally hundreds of feet of cable between the microphone and the recording equipment in the control room. Because the signal strength coming out of a microphone is very tiny, a line driver is needed, otherwise the sound quality would be quite degraded by the time the actor’s voices reached the recording gear. There are portable line drivers built into a cart that is wheeled around the studio and parked near each set. The microphone cable is plugged into the cart (and the line driver) and the audio signal is boosted in volume so that it reaches the set sound control room without degradation. The principle of the line driver is applicable to any situation where very long (over 100 feet or so) cables are in use.


LINE INPUT:       An input on a mixboard or other equipment designed for plugging in sound signals that are at line level. (See LINE LEVEL below.) This is as distinguished from MIC INPUTS, which accept the much lower volume level input signals that come from microphones.


LINE LEVEL: An audio signal volume level put out to the rest of the equipment on the line (mixing or listening). It is the basic, original volume of signal which can then be lowered or amplified louder by subsequent equipment settings. Note that “line level” is different from “mic level” (microphone volume), which is a much lower volume level. The volume level put out by a CD player would be the “line level CD volume”.  Any changes in that volume later by different equipment (mixboard, preamplifier, etc.) is said to be “changing the line level”.  Line level is usually kept high enough by source equipment to get a good quality signal down the line and to give plenty of potential volume. It is any signal from a source device that requires pre-amplification and amplification before it is sent to a loudspeaker. It is the audio signal used to go from one piece of equipment to another. Depending on the system, “line level” can be anything from -20 dB to +20 dB. Most audio equipment outputs signals at line level.


LINE LEVEL INPUT:   The input connection points on a mixboard or mixing device that accept a line level signal. (See LINE LEVEL.)


LINES OF RESOLUTION:  A term regarding how many lines are present in a TV’s picture screen or a video projector’s projected image. The lines run across the screen and there are many individual lines from top to bottom. Analogue broadcast TV in the USA is about 330 lines, a DVD is 480 lines, 525 is the lines of resolution of the Gold On-Line Bay. 720 and 1080 lines are considered High Definition resolution. These lines may be either progressive or interlaced. (See PROGRESSIVE SCANNING for more data on lines of resolution)


LINK:     1) A group of connecting points, called “jacks” on a patchbay which are mounted right next to each other and are pre-connected together internally so that by just plugging into one jack, the signal is routed to all jacks in a given link. Usually a link has 3 to 5 jacks. Any of the jacks can route the same signal to some other location. Links make a convenient way of sending one audio signal to several different pieces of equipment without having to use a patch cable. They are also very useful for plugging a meter or other testing device into a mix line. 2) The action of linking together several pieces of equipment using a link in a patchbay. 3) Broadly, any connection or interconnection.



1) To connect up two or more computers or computerised audiovisual equipment, such as an audio recorder and a video recorder so they operate together.

2) Broadly, to interconnect any equipment to use it for a specific purpose.


LIP SYNCH ERROR:   Any time a film or video’s audio is not properly synchronised to the pictures so, for people pictured talking, their lips are out of time with the words heard. Also called A.V. delay or out of synch.  This can occur as well when producing a video as the pictures are often sent through numerous pieces of video processing and effects equipment, each slightly delaying the picture in time relative to the audio. Therefore the audio has to be intentionally delayed as well.


LIQUID AUDIO:  A type of computer software used for mastering, serving and distributing copyright-protected music over the Internet.




LISSAJOUS PATTERN:      This is a pattern shown on an oscilloscope displaying both the horizontal and vertical lines summed as one image. Its most common use in an audiovisual studio is for adjusting the azimuth of tape recorder heads.


LISTENER ENVELOPMENT:      The sense in which a listener perceives he or she is “enveloped” (wrapped up in) the sounds as heard over a stereo or surround sound audio system.


LISTENING AREA:      The primary seating area from which listeners hear performed or reproduced sound.   


LISTENING DISTANCE:    The distance from the listener to the loudspeakers. 




LITZ WIRE:  A type of wire used to connect up audio equipment. It has very fine strands of wire woven into a braid. It forms a core of braded wire. Usually Litz wire, each individual strand, is coated with some form of varnish to insulate it from all other wires. You may not see the varnish, but it is there and must be removed by a hot soldering iron before it can be successfully soldered to a connector.



1) Describes an acoustical space having a great deal of reverberation.

2) Pertains to the sound of actual instruments or voices in a real performance occurring in PT.

3) The recording of such a performance.


LIVE EVENT EDIT MASTER (the “LINE CUT”):   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.





1) Any room that does not have many interior items or treatments to deaden (absorb) sound. A room that has reflective surfaces which will reflect sound.

2) Some recording and mixing studios have a separate room in which to check their products that more approximate rooms in normal consumer homes. Often the studio control room is treated acoustically to control and deaden reflections of sound. Most consumers’ homes do not have such treatments. In a “live room”, the studio installs a fairly good quality, representative stereo and surround sound system upon which mixes can be checked to ensure they will play properly once released.


LIVING PRESENCE:   A type of recording made in the late 50s and 60s when stereo audio was first made available. The full name is “Mercury Living Presence”, produced by the Mercury company.  They used 35mm film, completely coated with sound recording material to record the performances of the most famous orchestras playing the greatest works 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.


L, LC, C, RC, R:   In Sony’s SDDS professional surround system, the front speakers are Left, Left Centre, Centre, Right Centre, Right. Said not to exclude the fact that there are also surround speakers plus subwoofers, but when specifically speaking about or dealing with the front speakers behind the screen.


LNB:       Low Noise Blocking converter. An amplifier inside a satellite dish that picks up the transmitted signal. The arm projecting from the dish contains the LNB. This device blocks low frequencies and receives high frequencies from 12.2 GHz to 12.7 GHz for optimum signal reception. It then converts them to a signal that can be played by a TV set.


LNP-2:   The model number of a preamplifier that was produced by Mark Levinson in the late 1970s. These preamps were used on Gold’s sound lines until the mid 1980s when they were replaced by the MSP-1 (Master Stereo Preamplifier Version 1.) which was designed and built at Gold.


LOAD:    1) To copy the digital data off a storage medium (such as a floppy disc) into the RAM (random access memory) of a computer. 2) To put the tape on a tape machine and activate the computer-controlled constant tension system. 3) In electronics, the amount of resistance that the input of one piece of equipment presents to the output of the previous piece on the line. For example, a loudspeaker presents a load to the amplifier driving it - the load being the amount of work the loudspeaker makes the amplifier do - as regards how much signal current is required. As an analogy, a fire hose puts a lot more load on a reservoir than a garden hose does. It draws more water from the reservoir. It’s a very similar concept with electronic equipment.


 LOAD-IN:    The action of taking the mix from analogue tape and inputting it into SADiE is called “Load-In”.


LOADING:     1) The action of assembling the separate sound elements of a film or video so that the soundtrack can be mixed. For example, when a film’s soundtrack is to be mixed, the original sound from the set, plus the sound effects, narration and the music tracks all have to be assembled (“loaded”) in exact sequence and in perfect sync with the edited pictures for mixing. The separate audio tracks are all loaded into Pro Tools for the final mixing of the film or video soundtrack. 2) To transfer from one computer data storage medium to another.


LOADING THE ROOM or LOAD THE ROOM: A term used to describe not just filling the room with sound, but filling it with the power and presence of the sound by having a loudspeaker system of suitable power and of enough size or number to really activate the air in the room with the sound. By especially ensuring the lower frequencies (bass) are full and present, one can give the impression that the music is right “there” with impact, size and presence. Any good stereo or theatre audio installation will “load the room” with sound. The air within the room is literally “loaded” with sound.


LOBE, LOBES:      Portions of sound frequencies which build up within a room and therefore cause distortions and disturbances of other frequencies.


LOBING:       The tendency of a speaker system that consists of more than one individual loudspeaker to produce an uneven frequency response, with volume build-ups at certain points in the room.


LOCALISATION:  In audio reproduction, the placement of images (the reproduced instruments) in specific spatial positions around and between and behind the loudspeakers themselves.


LOCATION RECORDING:  Any recording done outside a studio can be called a “location” recording. Usually location recordings are those done at the actual site of an event or performance instead of in the controlled environment of a studio. This type of recording and film-video shooting requires equipment specially suited to travelling, and being rapidly set up and taken down.  


LOCK:    To prevent data from being edited, discarded or renamed, or to prevent entire computer storage banks or discs from being erased or altered by engaging a “lock”. This may be a physical or electronic function which, when activated, prevents potential loss.


LOCKED UP (OR LOCKING UP):     1) When two or more audiovisual machines are operated perfectly in synchronisation (such as tape recorders or video machines in a studio) they are said to be “locked up” (running together). 2) When synchronised machines first start up together, there can be a brief moment before they “lock up” (start running in perfect synch). They are said to be “locking up” during that time period. 3) Any audiovisual machine is said to be “locked up” if a tape is jammed inside or there is some mechanical trouble preventing its operation. 4) When a machine will no longer operate it is said to be “locked up” (jammed).


LO FI:    Cheap audio equipment as found at discount stores. The least expensive audio equipment from electronics stores. There is also “mid-fi” (slightly better and more expensive than “lo-fi”) and “hi-fi”. (Compare HIGH FIDELITY.)


LOGARITHMIC VOLUME CONTROL:      The type of volume control on most audio equipment that progressively raises the volume less as the knob is turned up more towards its most clockwise (loudest) position. One of the main reasons for this is that when one first starts to turn up the volume of an audio program (from no sound to the lower volumes), the knob needs less fine an adjustment to safely bring the volume up to the desired volume level. Once the volume is loud, one needs more “play” in the turning so that finer adjustments can be made. 

For a more detailed definition, read on… The word “logarithm” means how many times a number has to be multiplied by itself to equal a given number. They are usually written like this: 102, where 10 is the basic number and 2 is the logarithm. The “given” number in this case would be 100 (10 X 10 = 100). The progression of logarithms goes on (2 log10 = 100; 3 log10 = 1,000; 4 log10 = 10, 000 and so on). This type of progression can also be applied to a volume control. If you rotate the volume control knob on a preamp, the volume increases as you turn it clockwise and decreases as you turn it counter-clockwise. The volume increases or decreases on a gradient scale as you turn it. At the bottom (counter-clockwise) range (lowest volume) of the volume control, the gradient changes in volume are greater than at the top range (clockwise and highest volume) of the control.  At the clockwise end of the knob (the full-volume end), turning the knob ¼ turn will only increase the volume a few decibels. But if the knob is fully counter-clockwise (all the way down), bringing it ¼ turn up from there would change the volume by about 20 decibels. The relative change in the volume is much less at the top end (loudest setting) of the volume knob. Because the volume changes are in multiples of decibels rather than just addition (1 + 1 + 1, etc.) it is referred to as a “logarithmic volume control”. This design makes a more user-friendly volume control for the operator. It also, for example, complements the way power amplifiers for loudspeakers work, because it takes much more power in an amplifier to increase the loudness of the sound produced when it is at the top of its capacity than it does when it is well below its capacity, so a finer adjustment is needed at the loudest volume levels. A logarithmic volume control is also referred to as “audio taper”.



1) In audiovisual equipment, the various controls such as “PLAY”, “STOP”, etc. are said to be the “logic controls” or the “logic functions” on the equipment.

2) A “logic circuit” is a switching (on, off) electronic circuit that performs arithmetic logic functions that are used to control a portion of a machine or a computer. One example of a logic circuit’s math function is, “if the incoming voltage is higher than 2 volts, that equates to “on”, and if it’s lower than 2 volts, that is “off”. Professor Boole (1816 - ‘64), an English mathematician, devised a system of symbols for logic and logical operation, with synonyms for “and”, “or”, “not” and other terms. These symbols each represent a math operation. Boolean Algebra, in which all variables have the value of either 0 or 1, is the basis of digital computers.


LOG IT,LOGS:  After a mix has been done, all the settings on any piece of equipment used in the mix must be “logged” (written down). This is usually done on line drawings of the equipment showing all its knobs and positions. Such admin is always kept for future reference. It documents the mix.




LONG THROW:    A type of loudspeaker for professional applications such as shows indoors and out, which can throw its sound to a far distance. Usually, a good PA system for a concert or event will be a mixture of short throw and long throw loudspeakers. The long throw speakers are aimed to audience members located toward the rear of the venue and the short throw speakers are aimed at the audience members closer to the stage. Technically, “long throw” refers to the distance the loudspeaker itself travels back and forth when it reproduces sound. This travel back and forth is called “excursion”. Speakers with a long excursion tend to project their sound out a greater distance than those designed with a short excursion. (Compare SHORT THROW.)


LOOP:    1) A complete circuit for electrical current. 2) A film whose ends have been spliced together so that it will run continually.


LOOPING:    Modern music being composed and produced with the aid of computer depends greatly upon “looping”. Small bits and pieces of music, called “cells” are recorded into the computer, manipulated in various ways, then looped together so they repeat over and over throughout a given song. There is quite a lot of artistry involved in looping. Clever and creative editing of sounds is key. The entire rhythmic character and pace of modern songs is often established by this process. Looping has been around for many years. Originally, guitarists would have little tape recorders in the late 60s and 70s which would record a series of notes as the guitarist played and repeat them over and over, as the guitarist continued to play new notes over the recorded and looped sounds. When keyboard synthesisers came into use, a single note or series of notes could be stored in the synthesiser’s computer and repeated. Different sounds could be built up and entire songs created by this process of looping the sounds together. More advanced looping is done today with the use of sophisticated computers that can literally do about anything with a given sound. This is a key aspect of sound designing new songs and is used often for such.


LOOSE:  Pertains to bass that is ill defined and poorly controlled. Similar to “flabby”. A poor quality bass (any low frequency sound), or how a poor quality or broken bass loudspeaker operates.


Lo-Ro:   Left only - Right only. These symbols indicate a standard left-right stereo mix that has been created from a surround mix that was done first.


LOSSLESS COMPRESSION:      A method of data compression in which no data is lost. It is a higher quality form of compression over lossy methods. (See COMPRESSION 3 for more data on what compression is and how it works.)


LOSSY COMPRESSION:    A method of compression in which some of the data is intentionally not stored on the recording medium. This data is not recorded, it is lost - thus the term, “lossy”. Lossy compression attempts to mimic the way a person perceives sound by not recording sounds which are hidden or masked by other sounds that are similar. Lossy compression techniques don’t record and store such sounds, so therefore less storage space is required on digital media (DVD’s, etc.) (See COMPRESSION 3 for more data on what compression is and how it works.)


LOUDNESS:  Loudness is the perceived volume level (how loud or how quiet is a sound.


LOUDNESS BUTTON or CONTROL:        See FLETCHER-MUNSON EFFECT for full definition of this word and for the correct use of the “Loudness Button”.


LOUDSPEAKER(s), SPEAKER(s):   A device for converting a sound signal in the form of electrical energy into acoustic energy which one can hear. It is the exact point in a sound system where the electrical vibrations become air vibrations. There are many different types of loudspeakers - some are for professional live show or concert use, some for recording and mixing studios, others for home use, etc. Often a delineation is made between a loudspeaker’s cabinet and the actual speakers mounted inside. Individual speakers are called “drivers”. The whole cabinet plus drivers is called the “speaker” or “loudspeaker”.


LOW BASS:   The range from 20-40 Hz.


LOW END:    1) Refers to the bass note - the bass frequencies. 2) Poor, cheap quality audio or video equipment as sold at places like K-Mart. 3) Low quality.


LOW FREQUENCY:     Usually agreed upon as any sound frequency lower than 160 Hz. 




LOW FREQUENCY EFFECTS WOOFER (LFE):      The loudspeaker in a surround sound system is designed specifically to reproduce the low bass sounds (20-160 Hz). Adds dramatic impact to car crashes, gunshots, explosions etc.


LOW FREQUENCY ELEMENT:   The bass frequency portion (element) of any sound, mix or loudspeaker audio system.




LOW IMPEDANCE:     A method of sending the signal from one piece of electronic equipment to another where the voltage is relatively low and the current is relatively high. 500 ohms or less impedance.


LOW IMPEDANCE MICROPHONE:  A “low impedance microphone” has an output impedance of 500 ohms or less. Most high-quality professional microphones are low impedance. (High impedance mic’s are rarely used in a professional recording studio, unless one is using it for a specific effect.)



1) Audio signals or sounds, such as those heard over loudspeakers, that are very low in volume.

2) Referring to an audio signal that has a much lower strength than line level. Usually low-level is referring to microphone level signals, which have quite a low output compared to such things as a CD player, a tape recorder, an A.V. receiver, etc.

3) Referring to line level signals when they are being compared to speaker level (the signal going from amplifier to loudspeaker). 4) A signal in the range from minus 100 dB to minus 20 dB. Microphone and electric guitar signals are in this range. (Compare LINE LEVEL.)


LOW-PASS FILTER:    An electronic circuit that acts to allow frequencies below a selected frequency to pass through it and stops any frequency higher than the selected one.  For example, a low-pass filter set for 10,000 Hz will allow any frequency lower than 10,000 Hz to pass through and stops those higher than 10,000 Hz. The definition of “low” in this case is any frequency lower in pitch than the selected frequency.


LOWER HIGHS:   The range of frequencies from 1.3 to 2.6 kHz.


LOW-LEVEL DETAIL:  The subtle, very low in volume nuances of sound, which include the fine details of sounds and the tail of reverberation decay. Over excellent loudspeakers and audio equipment, low-level details can be heard.


LOWER MIDDLES, LOWER MIDRANGE:       The range of frequencies from 160 - 320 Hz.


LOW Z or LO-Z:   Low impedance. “Z” is the electronics symbol for “impedance”. Impedances of 500 ohms or less.


LOW PRINT TAPE:     Tape that will have a low level of print-through (one layer of tape magnetising the next layer).




LOW-NOISE TAPE:     Alternate name for High-Output Tape. Recording tape that can be recorded with a higher magnetic level (volume) than “standard” tape and because of this, has a better signal-to-noise ratio. This term is actually pretty meaningless nowadays, as virtually all magnetic recording tape manufactured since the 1960s is “low noise, high output tape”.


LOWS:   Bass. The low frequencies.


LP:  (Long Play)

1) The medium speed at which a video can be recorded on home consumer video decks. A standard one hour videocassette will record and play back one and a half hours of program. Compare to SP (Standard Play) and EP (Extended Play).

2) A setting on a Panasonic DVD-RAM recorder that has the lowest quality and also uses the storage space of the DVD up slower than the SP (Standard Play) position. A DVD-RAM recorded in the SP position holds a maximum of 2 hours of program and LP holds up to 4 hours. (See DVD-RAM.) 

3) Refers to a phonograph record that plays at 33 1/3 rpm and is thus “long-playing” as compared with the older 78 rpm records. 


LPCM:    Linear PCM (Pulse Code Modulation). See LINEAR PCM, PCM.


LPTV:     Abbreviation for Low Power Television. These are TV stations meant to broadcast only to a limited range of consumers. Examples of LPTV stations include some local TV stations, public and educational stations and college TV stations.






LRH FINAL LECTURE MASTER or LECTURE REVERB RUNOFF:       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. (See MASTERS, TYPES OF for a full listing of the audio and video masters used at Gold.)




LRH LECTURE EDIT MASTER:  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.) 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 MASTERS, TYPES OF for a full listing of the audio and video masters used at Gold.)


LRH LECTURE SAFETY MASTER:     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.)  The Safety Master is a final master run-off of the mix and kept secure. It is never edited. (See MASTERS, TYPES OF for a full listing of the audio and video masters used at Gold.)


LS:  Abbreviation for Left Surround - The left surround channel in a surround sound audio system that has “stereo surrounds” (2 channels worth of surround information and loudspeakers). The other surround channel is called Right Surround (RS).


LSB:       Abbreviation for Least Significant Bit. “Least significant”, in terms of number value, means that an individual digit’s position in a number has the least effect on the magnitude of the overall number. For example, in the number 10,245 there are five digits. The least significant digit in this number is “5”, as it has the position of least magnitude. The “significance” of the numbers in this example graduates from least to most in the sequence… 5, 4, 2, 0, 1 - with the number 1 in this case being the MOST significant digit. Bits work the same way in the binary numbering system. In the binary number 1001, the 1 furthest to the right is the least significant bit and the 1 furthest to the left is the most significant bit.  In a digital audio signal, for example, the least significant bit (LSB) is the bit that records the sound signals of the lowest volume (including the subtle parts of the sound’s characteristics). The most significant bit (MSB) records the audio signals of the loudest volume.


LSB TOGGLING:  LSB is an abbreviation for Least Significant Bit. “Toggling” means turning on and off or switching back and forth from one thing to another. The least significant bit in a series of data bits is the one that records the lowest volume sounds. When the LSB “toggles”, it is switching on and off and thus recording data that represents the subtlest parts of the audio program - such as ambience, reverb tails, etc. When the LSB is toggling, it is actively storing (and playing back) data.


LSI: An abbreviation for Large Scale Integration. This is a designation for an integrated circuit. The LSI designation means that an integrated circuit (chip, microchip, etc.) has a large amount of operations that it can do. An LSI integrated circuit (chip) has between 100 and 5,000 individual circuit elements built into it. This is in comparison to a Medium Scale Integration (MSI) chip, which has from 10 to 100 elements and SSI (Small Scale Integration) chips which have fewer than 10. Any integrated circuit performs a lot of electronic operations but the LSI and super LSI (SLSI) chip are the types that perform the most functions. (SLSI chips have between 50,000 and 100,000 elements built into them.)


LTC:       Longitudinal Time Code. Time Code information encoded in binary coded decimal form which is recorded as an audio signal on a designated track of a VTR or ATR. It’s called “longitudinal” because it is recorded along a linear line on the tape. (See TIME CODE.)


Lt-Rt:     Left total - Right total. (Note:    Does not stand for Left track-Right track.) A stereo recording can have imbedded within it information that is used by a surround sound system to expand those 2 tracks into surround sound when playing back. The designation “Lt-Rt” on a master tape or audio computer file means that the recording has been done onto 2 tracks and is intended to be played on a surround sound system. The surround sound equipment receives the Lt-Rt signal and interprets its data to play back in surround sound. (Compare with Lo-Ro.)


LUMEN: A unit of measurement of light equal to the brightness of one candle. The word “lumen” comes from Latin meaning “light”.


LUMINANCE:       1) Intensity of light emitted, reflected or transmitted, per unit area of a surface. Also called brightness. 2) The black and white component (parts) of a video signal. Represented by the letter “Y” in video technical terminology. 


LYRICS SERVER: An Internet service that allows one to search for the lyrics to any song, and hear the song. (