Audio-Visual Glossary



NAB: National Association of Broadcasters. An American agency that sets standards for audio engineers.


NAD: Acronym for New Acoustic Dimension. Brand name of a company that manufactures inexpensive, but fairly good, reliable home audio equipment.


NAGRA: The name of the line of professional ¼ inch tape analogue and digital recorders manufactured by the Kudelski company of Switzerland. Their battery-operated portable analogue recorders, especially the 4.2 mono and IV-S stereo models were the standard of the motion picture industry for over 30 years. Nagra means “recorded” in Polish, founder Stefan Kudelski’s native language.


NAGRA-D: Stands for Nagra Digital. A digital audio tape recorder used at Gold mainly for film location sound recording. The Nagra-D has four digital audio channels and a separate channel for time code. It uses ¼ inch digital tape on reels and records up to 2 hours of program on a single reel of tape. 


NAKA COPY BATTERY: “Naka” is short for Nakamichi, which is the name of a Japanese company that manufactures high quality cassette recorders. The word “battery” in this case means a group of machines that are interconnected and that operate in unison. Golden Era Productions has a battery of 12 Nakamichi 582 model cassette recorders set up to make very high quality copies for limited edition cassettes. (See NAKAMICHI.) 



NAKAMICHI, “NAKA”: Brand name of a high quality cassette recorder.


NAKAMICHI CASSETTE DECK (front panel controls - what they are and do): There are many buttons and symbols on the front panels of the Naka cassette decks. These symbols are not peculiar to only Nakamichi equipment. Virtually every brand of cassette recorder and most brands of cassette tape have similar symbols written on them. The following is a list of these symbols and their definitions.


TAPE SELECTOR EX (I), SX (II), ZX (IV) or Type I, Type II, Type IV

The tape selector buttons are used for the several different types of cassette tape that exist. On some models, the tape selector buttons are for recording only. (Note: Though the Standard Tech Cassette Deck is intentionally made unable to record to prevent possible erasure of LRH lecture cassettes, some Nakamichi models do use these buttons for playback as well as record. For listening to LRH lectures, the ZX (“Type IV”) button should be pushed when listening on Nakamichi models DR 1, DR 3, DR 8, and DR 10.) See the Standard Tech Cassette Deck manual for instructions. Note that for listening to LRH lectures the “ZX (IV)” button should be pushed for listening to LRH lectures on Nakamichi models so designated in the instruction manual. There are 3 basic cassette tape types. Each uses a different type of metallic particles upon which recordings can be made. The normal tape is ferric (iron oxide), then chrome, and the very best is called “metal”. When the correct button is pushed, the cassette player’s electronics apply the correct electronic processing needed for that type of cassette tape. The 3 tape selector positions are “EX (I)”, “SX (II)” and “ZX (IV)”.


These terms, per Nakamichi, were just made up letters and numbers for marketing their tape brands. As a matter of fact, on some of the newer Nakamichi cassette decks, they dropped using these letters and just call the buttons “Type 1”, “Type II” and “Type “IV”. Other brands of cassette tape also adopted this naming system and on earlier cassette decks you will still see such. EX is tape type one (I), the normal ferric tape. SX is tape type two (II), chrome tape, and ZX is tape type four (IV) which is metal tape, the highest grade. There is no tape type three. The cassette tape manufacturers just skipped the number.


EQ (µSec) 120, 70

There are two positions for this pushbutton and you are to push it “in”. When you use this button, you are telling a cassette deck what type of tape (ferric, chrome or metal) is being played and the cassette deck then knows how to reproduce the sounds accurately. The cassette deck will play the tape with an equal balance of all sound frequencies (treble, midrange and bass). “EQ” is an abbreviation for “equalisation” which essentially means “to make equal”. The next term on this button is an odd one - it is “µSec”. That small symbol “µ“ stands for “micro” which means 1/1,000,000 (a millionth). “Sec”, of course, stands for “seconds”. So, “µSec” stands for “millionths of a second”. Now, audio equipment engineers and designers deal with sounds, and sounds are “frequencies” (vibrations per second). These designers have a mathematical formula that equates time to frequency. In other words, they can assign a length of time to a frequency and know that that time equals that frequency. They measure all this in “microseconds” (millionths of a second). There are two numbers next to this button - “70” and “120”. When you press the button, you are telling the machine to calibrate itself to “120 microseconds” or “70 microseconds” -- and those terms actually equal a certain frequency of sound that the machine then uses to orient itself to best play the type of tape you have put into the machine. Metal cassette tapes require that the “70 microsecond” setting be selected.  (More information at the entry in the “S” section at “70 µSec EQ or 120 µSec EQ”.)



Note that on some cassette decks and cassette tapes you see the symbol CrO2 which is just the chemical formula for chrome tape (Cr = chromium and O2 = oxygen). Chrome is a type of metal particle used to record sound on some types of cassette tapes. It is the same setting as “SX (II)” mentioned above. The Nakamichi cassette decks used in org course rooms don’t have this term on them, but if you are listening to an LRH cassette tape at home on a cassette deck that does, you want to press the button that says METAL (on some cassette decks the “metal” and Cr O2 settings are combined on the same button position in which case select the METAL or Cr O2 position).




These are the buttons that activate (turn “on”) or deactivate (turn “off”) the Dolby Noise Reduction (NR) system. Dolby B and Dolby C are different types of noise reduction. “Noise Reduction” is a process, developed by Raymond Dolby, used on most tape recorders because tape, regardless if it has any sound recorded on it or not, actually will produce a “hissing” noise as it plays. Even blank, unrecorded tape will make this noise. “Noise Reduction” electronically gets rid of this noise. However, the correct type of noise reduction is vital. There are two types - “B” type and “C” type. Always use “Dolby B” for all cassette tapes produced by Gold. Activate this feature of the cassette deck by pressing the “Dolby NR button“ to its “on” position (press it in). And then press the “B, C” button to ensure it is in the “out” position (which is for “Dolby B” ). 



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 like to record music and programs 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.



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.



The “RESET” button, when pushed, sends the tape counter back to “000”. It doesn’t move the tape, it just resets the counter numbers.



Some consumers wish to record a radio program at a certain time during the day, but they may not be in the house. So, they could use a timer which will turn the cassette deck on at the desired time. Nakamichi never sold a timer. But consumers could purchase one from Radio Shack or wherever, plug the Nakamichi deck into the timer and the timer into the wall outlet, and the Nakamichi would start right up. PLAY or RECORD could be pre-set to happen when the timer started.



There are actually two control knobs associated with this feature.

One sets the volume of a recording one wishes to make, and the other balances the volume between the left and right channels so one can get equal volumes in both ears (or over both loudspeakers) for any recording made. The org cassette decks have their recording feature disabled to prevent LRH lecture cassettes from being accidentally erased. So this is a feature you will never need to use when in the course room.



On some newer Nakamichi models the tape selector has buttons for “TYPE I”, “TYPE II” and “TYPE IV”. (There is no TYPE III). These selectors are for recording and playing back onto the different types of cassette tape, just as the EX, SX, and ZX buttons listed above. Tape type I is normal ferric tape. Tape type II is chrome tape and tape type IV is for metal tape.



This knob is for adjusting the amount of bias used to record onto a cassette tape. The Nakamichi org cassette decks are not able to record so this is a feature you will never use.)



Older Nakamichi decks had this same switch, only labelled “TIMER”. See TIMER above. In the “AUTO REPEAT” position, the Naka will automatically rewind and replay the same side of a cassette once it reaches the end of a side. The “PLAY” and “RECORD” settings of this switch require an external timer unit as noted above.


NAKA 1000 ZXL, NAKAMICHI DRAGON: The Nakamichi Company designed and built the highest quality tape cassette decks in the world. Their best was the Nakamichi 1000 ZXL and then the NAKAMICHI DRAGON. These cassette decks have many features, including an automatic computerised self-tuning function that will fully set the machine up to optimally record onto the exact type of tape cassette that is put into it. There are Naka 1000 ZXLs on the Lecture Mix Line, Studio One, Studio 2, Lower RAV and other production lines. Their main use is to QC how the product will sound in the cassette format.


Nano-: A prefix for one billionth, abbreviated “n”.




NAPSTER: An Internet site which provided music which can be heard and-or downloaded to MP3 players. Napster was started by an 18 year old who, in a 60 hour blitz, wrote a computer program that allowed music to play over the Internet and be accessed and downloaded. It was a huge flap in the music industry as royalties were not getting paid. Bertelsmann Music (BMG) ended up purchasing the site from the youngster for millions. It is now an Internet site that Bertelsmann uses to promote and sell their own record releases.


NARM: National Association of Recording Merchandisers. This association is involved with watch-dogging music properties being played over the Internet and it works to establish rules and distribution methods that protect the music industry.


NASAL: Reproduced sound having the quality of a person speaking with his or her nose blocked or through the nose. Like the vowel sound "eh" coloration. It’s a sound like people talking from high up in their noses. In a loudspeaker, often due to a peak in the upper midrange. Some loudspeakers will sound “nasally” due to cheap materials and poor design.








NATIVE, NATIVE RESOLUTION: Said of audio and video products to describe their preferred or basic method or rate of duplication or reproduction of an A.V. source. For example, your computer screen has a “native resolution” - the total number of lines or dots that the screen is capable of using to present an image. Under some circumstances, the screen might be adjusted to operate using less than it is capable of producing. It would then not be operating at its “native resolution”. Another example: Some video projectors used for professional applications and by consumers can have their native resolution increased by electronic manipulation done by other components. The picture can be made to look better than the projector was originally designed to do.


NATURAL ACOUSTIC SPACE, NATURAL ACOUSTIC: Said in sound recording and mixing to refer to the fact that some types of music performances and audio presentations (lectures, etc.) have their “natural acoustic space” - meaning the actual room, hall, outdoors, etc. where the recording was done.


NATURALNESS, NATURAL: Realism. The quality of music that sounds “natural” (as one would think it should realistically sound). “That synthesiser produces the sound of violin strings with excellent naturalness.” (Compare COLOURATION, COLOURED.)




NBS: (Nothing But Sound) This is the manufacturer of high quality audio wire, speakers and amplifiers.


NEAR FIELD, NEARFIELD: The region within approximately six feet of loudspeakers. When one listens to speakers sitting very close to them, one is said to be “listening near field”. Pertains to that range of listening distances in which the sounds reaching the ears are predominantly direct as one is not so far away from the speakers as to also hear their sound reflecting off any surfaces in the room.




NEAR FIELD MONITORS, “NEARFIELDS”: (See the entry under NEARFIELD above.) Professional quality loudspeakers (monitors) which are placed very close to the listener (Mixer), usually on the top front area of the mixboard. These speakers are small and usually very accurate. Because the Mixer (or any listener) is so close to them, one hears their sounds very directly, without much influence coming from their sounds reflecting off room walls or the mixboard itself. Usually the loudspeakers themselves are “tuned” so as to account for the fact that some of their sound (mostly their bass region sounds) will reflect off the mixboard itself and add back into their own sound quality. Such speakers may sound thin (lack bass) if not used for the purpose intended (sitting on a mix board). One usually mixes on both nearfields and the large main studio loudspeakers comparing both to ensure one’s mix will play well on all sizes of loudspeakers.


NEC: Abbreviation for Nippon Electric Company. Trade name of a Japanese electronics manufacturer of video equipment, computers and computer, TV, video screens.


NEG ELEMENT, NEGATIVE ELEMENT: Said generally to refer to any type of negative which is to be used in a printing process. (See NEGATIVE 1.)      


NEGATIVE,1 NEGATIVES: The word “negatives” refers to the film that was originally shot in the camera to photograph a scene or image. (Note: It is called “film” until it is exposed - then it is called a “negative”.) A “negative” is an “opposite”. It is an “opposite” picture so to speak. When you look at a negative, all the blacks are white and the whites are black. It is all opposite in colour. As well, all the images are backwards too. If the picture is of a house, the house will look like it was built backwards in every respect. If the house has dark red bricks, they will look like white bricks when you look at a negative. The images are opposite in colour and in what direction they actually appeared in front of the camera. However, when that negative is used to make a print - a copy of a picture you actually can see - all the images come out perfectly fine. Correct colour and all the objects are in their right location, just as when the camera took their picture. This is because the negative has a negative image, so it can be used to make a positive copied image. Here is how: When a copy of a movie film is made to be shown in a theatre, the film to be copied onto is allowed to touch the negative during the copying process. Light is shown through the negative onto the touching film. That bright light exposes the film being copied onto. Because the negative and film are touching, the images on the copy come out correctly located, much like if you hold your two hands together, the right hand is exactly the opposite in direction to the left hand when you touch them together. It’s the same when the negative and the film to be copied touch. Additionally, all the colours come out correct too because the lighter areas of the negative allow the light to expose the film more - more light is allowed through in those areas - which makes the corresponding areas of the print copy darker. Conversely, the dark areas of the negative prevent light from passing, so the film does not become as developed in those areas. Those areas come out lighter in the copy process. Thus, the copy of the negative comes out just as the camera saw the image.




NEGATIVE FEEDBACK: “Feedback” as used in an electronic circuit is a very different definition of “feedback” than that describing the unwanted howl sometimes created in a live sound system. A “feedback” circuit is one that assists, inside an audio amplifier, to supply the most optimum amplification possible at all times. The circuit literally “feeds back” (back into the amplifier) a tiny portion of its output to help increase the amplifier’s volume. A “negative feedback” circuit is designed to decrease the signal internally inside an amplifier.  Negative feedback circuits are sometimes used as a method of reducing distortion and to make an amplifier operate more stably. This is as opposed to “positive feedback”, which is a type of circuit used in an audio amplifier to increase the amount (volume) of signal. 


NEG CUTTER, NEG CUTTING: The process of cleaning, cutting and assembling the original camera negatives of a film once its final edit has received full approval. The Neg Cutter is a very highly skilled specialist who cuts the most priceless element of the film, its original negatives. The Neg Cutter has the approved Work Print as well as a digital printout from the AVID computer where the film was edited. The printout gives the exact edge code numbers upon which to cut the negatives so that it exactly matches the approved video. The Work Print’s edit splices, and the frames they were done on, are checked first and used as the stable datum. 




NEOTEK: Brand name of an audio mixboard. An Internet site which gives full listings of abbreviations used frequently on the Internet and in e-mail.




NETWORK: A series of points in different locations connected by communication channels. Generally used to mean a multi-computer system (as opposed to a single computer system) where multiple access is allowed from more than one computer at a time. Characterised by full communication and accessibility among all equipment and computers on the network.


NEUMANN: Manufacturer of very high-quality microphones. One of the best and most used microphones for voice recording is the Neumann model U-87. The U67 is also excellent. Often used for singing as well as some narration recording.


NEUTRAL: Free from coloration; no alteration. This is an audio term used to describe sound having no particular unusual qualities. Audio equipment is described as neutral when it is considered to impart very few added qualities or degradation to the sound. (Compare COLORATION.)




NEVE: Brand name of a mix board manufactured by Rupert Neve Corp. of the UK.


NEW INTERPOSITIVE: The “New Interpositive” is made from the original cut negatives, but only after final QC approval is issued on the rough “Checkprint”. Original cut negs are then securely vaulted per Film Lab production line. (See INTERPOSITIVE)


NEW INTERNEGATIVE: The “New Internegative” is made from the “New Interpositive”. It is the actual negative element used to print the final test print. (See INTERNEGATIVE, NEW INTERPOSITIVE.)


nFs: An abbreviation for Nyquist rate of Frequency Sampling. (See NYQUIST FREQUENCY, NYQUIST SAMPLING THEOREM.)


NHT: Now Hear This. A brand name of home consumer loudspeakers.


NIBBLE: A “nibble” is a coined word in the field of computers. A nibble equals a total of four bits. Some very early computer chips could not process a full byte of data all at once. A byte has eight bits. They could however process a nibble, which is only four bits. In present time, the “nibble” unit applies to telephones. Every time you press a button on a normal digital telephone, like the one on your desk, you are generating one nibble of data.


NICAD: An abbreviation for Nickel-Cadmium, which are the materials used to make a type of rechargeable battery.


NICKEL METAL HYDRIDE: Chemicals used in a type of rechargeable battery. These are long lasting and do not tend to develop a “memory” (if the battery is not drained to dead each time it is used - some batteries “remember” where they are constantly drained down to, if not all the way, and will, after a while, only charge and operate to that point.)








900 TAPE: See BASF.




NINTENDO: A popular brand of computer game station presenting video games for home consumers to play. Also called a videogame console.




NMPA: National Music Publisher’s Association.  This association works to protect copyrighted music works. They are also involved in procedures to facilitate the licensing of songs distributed over the Internet.


NODE(S): An area in a room where sound drops down in volume due to the characteristics and influences of the room itself and its reflective surfaces. Also has to do with the size and dimensions of the room and other factors. (Compare to MODE.)


NO DYNAMICS: Sound that is flat and compressed. There is little difference between the low volume and loud volume sections of the recording or mix.


NOISE: Noise is unwanted sound. Some of these noises may be minimised or eliminated completely. Coughs, chair squeaks or the sounds of traffic outside may be removed by editing, doing a re-take, or sound proofing. Other noises are a function of the recording medium itself. For example, every component in the signal path, from microphone to amplifier, introduces a little noise into the system. This noise may be in the form of a hum resulting from faulty shielding or a hiss from an amplifier output. There are also noises that are a by-product of the magnetic recording process.


NOISE FLOOR: The level of the noise, in dB, below the volume of the meaningful audio signal. For example, all recording tape has a noise floor - it’s a very slight hissing sound, very low in volume, but audible. Dolby noise reduction is used to get rid of this.


NOISE GATE: An electronic circuit used in some applications to greatly reduce the volume of an audio channel when no signal is present. For example, if someone is singing into a microphone which is connected to a mix board channel and a gate, the gate is not active when the person is singing, but between the singer’s lines the gate acts to turn down the volume of that mix board channel. These are sometimes used to prevent excess noise from getting into a live mix. Gates are also used as a mixing effect on drums. For more technical data, read on...When the incoming audio signal drops below the user-set point (the threshold point) the gate prevents any further output by reducing the gain. The actual gain reduction is typically on the order of -80 dB, thus once audio falls below the threshold, effectively the output level becomes the residual noise of the gate, which should be virtually nil in an operational gate. Common terminology refers to the gate "opening" and "closing”. Another popular application uses noise gates to enhance musical instrument sounds, especially percussion instruments. Skilful setting of a noise gate's attack (turn-on) and release (turn-off) times adds "punch”, or "tightens" the percussive sound, making it more pronounced.


NOISE REDUCTION: Any device to remove noise in a device or system. 




NOISE SHAPING: (See the definition of dither first). “Noise Shaping” is a process done in digital audio equipment to improve the accuracy and naturalness of the sound. It is used in conjunction with dither. Testing revealed that the sound quality yielded by dither could be improved further if the dither noise was given less emphasis on some of its frequencies and more on others. (Dither noise has a wide range of frequencies.) In noise shaping, the more audible frequencies (such as the midrange) are reduced in volume and the less audible ones (at the lower and higher ranges of hearing) are increased in volume. This increasing and decreasing of the volumes of the different frequencies of dither is referred to as “shaping”. There are several different versions of noise shaping, each with its own characteristic combinations of frequency volumes - its own “shape”. The type of noise shaping used for a given audio program is based on listening tests done for each type of product.


NOMINAL: The middle range (average) of performance specifications of any audiovisual electronic equipment or electronic part. It is the value halfway between maximum and minimum limits of the tolerance range. 




NON-COINCIDENT WAVE FRONTS: Sound from two or more sources, such as the left and right loudspeakers in a stereo or surround sound audio system, that arrives not at the same time to the listener. If one loudspeaker plays a sound and the other speaker plays that very same sound, you would have to sit perfectly in between both speakers and have them perfectly aligned and distanced from your head in order to receive their sound at identical times. If one’s head is off to the side at all, the wave fronts (the waves of sound each loudspeaker is sending forth) will be non-coincident and therefore the sound will not be as present as it might if it were produced just by one loudspeaker, such as a single full range centre channel speaker in a surround sound audio system.


NON-DROP FRAME TIME CODE: SMPTE time code that does not drop a frame periodically to keep the signal in time with the colour video signal. (See DROP FRAME TIME CODE, SMPTE.) 


NON-LINEAR EDITING (NLE), NON-LINEAR EDITOR: By linear is meant that all the shots are recorded or spliced together in a line, one after another, as one edits along going through the film or video. However, if one wants to go back and change an edit, one then has to go back to where that edit is located in the program, do the edit correction, then re-record or re-edit everything again from that point to the end. This type of editing is called linear editing. Computers and computerised video editing equipment has made it possible to greatly speed up the editing process. One can edit and do as many edit changes as one wants, and it is all instant. There is no re-recording and no re-editing long sections of the show. It’s done by computer and the computer can handle automatically doing all the changes when any one edit is done so the whole show stays edited even though an earlier edit is somehow changed or corrected. This makes editing FAST and one can also take some time and try various methods of editing and do different edit versions and pick the one that works best - or use a combination of edits. Because one is not having to constantly record and re-edit over and over each time any edit change is desired, editing with the Avid is called “Non-Linear”.


NON 1-1 PROCESS: This is a term used in the SADiE digital audio computer manual. If two things are “1 to 1”, they are “equal” or made to match each other.  (The first “1” is exactly like the second “1”.) The term, “non 1-1 process” means that the duration of a copied sound, compared to the original sound, is changed. An example of this would be having an explosion sound effect that lasted 3 seconds in reality but it needs to be 4 seconds long in the mix for a video soundtrack. Using SADiE, one can lengthen (or shorten) the duration of the explosion. This is using the non 1-1 process feature of the SADiE system.


NON-REAL-TIME CD MASTERING:  This is a term used in the SADiE digital audio computer manual. The SADiE system is able to master a CD faster than real time. How fast it will go depends on the complexity of the EDL and the computer hardware being used. 

For more technical information, read on… The SADiE’s mastering functions will enable the master to proceed at a speed regulated by the computer hardware (which in practice may stop and start and perhaps change speed to accommodate different levels of complexity throughout the EDL). In non-real-time CD mastering, you will not be able to hear the audio as it transfers to the master. Also, because there is no audio playback in this mode, you will not be able to use any external processing during the mastering cycle. However, you can get around this by including the processing before the final mastering process.

Important Usage Note: When a CD is mastered faster than real-time, the quality may be poorer than one done at real-time speed.


NONVOLATILE: Refers to a computer memory storage that does not lose its data when electrical power is turned off to the computer or computerised audiovisual device. Often there is a battery backup inside. 


NORELCO: When cassette tapes are packaged, they are put inside a plastic box that is used to store the cassette. These boxes also usually contain things such as cover photos, lyrics and other information about the cassette. The Norelco Corporation is one of the chief manufacturers of these boxes and the name has become generic.


NORMALISATION: This is a technique in digital audio where the sound volume throughout a programme is made to be louder and the audio overall is made as loud as it can be before it would distort digital recording equipment. This process, called normalisation, is often done when putting music or other audio programmes on the Internet. Because the digital storage space and speed of digital data transfer is quite limited on the Internet, it has become a common practice to crowd the volume level of an audio programme as high as possible without distorting. In this way, as much of the audio information as possible is maintained. So, to get as much possible sound quality with what there is to work with on the Internet, the audio is made as loud as possible without it distorting. Obviously this is a compromise in quality, but it’s done to get any kind of intelligibility and presence at all. It is called “normalisation” because all the volumes are brought to a consistently high level (“normal”).


1) Some mastering facilities may attempt to normalise even a CD release, and some mastering computer equipment has such a feature that will do this automatically.

2) In some home theatre audio systems, the volume is not played loudly, especially late at night as it might wake the children and neighbours. But, the volumes of films go very loud and very quiet often. If the volume is too low, you will probably not be able to hear half the dialogue, but you will hear all the gunshots and earthquakes just fine. Therefore, some audio equipment gives the consumer the facility to “normalise” the volumes when playing at low volumes. The setting might be called the “Night Mode” or similar name, depending upon the brand of equipment one owns. By “normalising” is meant that the equipment itself automatically adjusts all the volumes of the surround sound system to stay constant (normal) so one can hear all the film, without playing it too loudly.


NORMALED: (AS IN A PATCHBAY BEING “NORMALED”) Switches on the patch jacks which connect certain jacks together until a patch cord is inserted. 


NORMAL MODE, NORMAL SURROUND MODE: A setting found on many home consumer surround sound audio equipment. “Normal mode” is selected when the consumer’s centre channel speaker is small and unable to produce full range audio (lacks bass). When the “Normal Mode” is selected, all the bass frequencies below 100 Hz are routed to the left and right speakers, which are usually larger in size than the centre channel speaker. (Many home surround audio systems use smaller centre channel speakers because the centre loudspeaker is placed on or below the television where there is not much room for a large full range loudspeaker. Therefore, “Normal” is when a smaller speaker is used - it is what is “normal” in such consumer systems.)


NOTCH: A narrow band of frequencies that are cut out of a signal.




NOTE: The derivation of the word “note” comes from the Latin word “notare”, which simply was a written mark indicating what musical tone was to be played. A note is any musical tone played on any instrument or sung by a singer.


NR: See Noise Reduction


NRC: This is a term used in the SADiE digital audio computer manual. Abbreviation for Noise Reduction Curve.  In computerised audio recording, mixing and editing systems, the NRC is a graphic display of the waveform of an unwanted noise that one is trying to remove. The display screen shows the frequencies of the unwanted noise and the volume for each frequency that makes up the unwanted noise. This display forms a line on the computer screen that can be seen to “curve” up and “curve” down as the noise is played (and heard).


NRR: National Recording Registry. A registry is a place where something (or someone) is registered (logged in, written down, noted, etc.) The National Recording Registry exists within the U.S. Library of Congress. It was established in Oct 2000, with the passage of “Work for Hire and Copyright Corrections Act of 2000”, which was a Clinton signed bill that allowed recording artists to reclaim ownership of their works and master tapes from music companies. Under the bill, artists can reclaim their tapes after 35 years. The National Recording Registry was also given a seal (a stamp) to identify recordings within the registry.


NTSC: National Television Standards Committee. The colour television standard for North America established in 1953. It is lower quality than the new High Definition TV broadcasting and equipment and lower than Digital TV broadcasting. NTSC specs are what a regular old (pre-digital television) TV is or a consumer VHS videocassette. For more technical information read on…NTSC has 30 frames per second, with 2 fields per frame. It usually operates at 330 lines of resolution on the screen.


NULL: 1) A condition of zero energy or movement, especially because of two opposing forces being equal. 2) In mixboard automation, the placement of the slide of a fader (or knob of a control) to the exact point that was originally used to make the automated mix as opposed to any new adjustments the Mixer may have made or tried. It gets the mix back to what was stored into the mixboard’s computer memory - no difference - therefore the “null” position. 3) Not adding or subtracting from a given volume of sound.


NYQUIST FREQUENCY: In digital audio recording, the highest treble frequency that can be accurately sampled. The Nyquist frequency is one-half the sampling frequency. For example, the Nyquist frequency of a CD system is 22.05 kHz, as a CD’s sampling rate is 44.1 kHz. Nyquist frequencies are sometimes written with the abbreviation of nFs (Nyquist rate of Frequency Sampling) as in nFs 22.05 kHz. (See NYQUIST SAMPLING THEOREM below.)


NYQUIST SAMPLING THEOREM: This theorem states that the sampling frequency of a digital audio system must be at least twice that of the highest audio frequency it will be required to record or process, otherwise distortion will occur. USAGE NOTE: The specification of 2X the highest audio frequency is made because at least two samples of each sound vibration need to be taken. Each vibration has a back and a forth - both need to be sampled, otherwise only a part of the vibration is recorded. In such a case, there would be an incomplete sample of the actual sound - heard as distortion. Thus a sampling frequency of over 40,000 Hz is needed to record a 20,000 Hz sound.