A coincident microphone technique, in which the M (middle) microphone is cardioid, pointing toward the middle of the orchestra, and the S (side) microphone is a Figure-8, with its dead sides on the same axis as the front of the cardioid.
A speaker comprising a ferromagnetic armature actuated by magnetic attraction.
Field of force in the vicinity of a permanent magnet or an electric circuit carrying current.
A speaker in which acoustic waves are produced by mechanical forces resulting from magnetic reaction.
Recording medium in the form of a plastic tape (cellulose acetate, polyvinyl chloride, polyester) coated or impregnated with magnetizable powders.
Manual record-playing device used with a changer-type machine.
1. The process by which the threshold of hearing of one sound is raised due to the presence of another 2. The increase, expressed in decibels, of the threshold of hearing of the masked sound due to the presence of the masking sound.
A recording, in edited or approved form from which copies can be made.
Lacquer-coated aluminium disc 14 inches in diameter for a 12 inch record and 10 inches for a 7 inch. When completed, the lacquer disc is coated with silver to make it conductive for electroplating with nickel. This is done in two stages: a slow, precise coating to plate the grooves with 1 mil of nickel, followed by a faster build-up of 20- 30 mils. The nickel is then parted from the lacquer to form a negative metal master disc having ridges in place of grooves. Although this could be used to stamp out the final pressings, it is much too fragile. The next phase is to produce the mothers.
A tape having from 16 to 32 tracks records all microphone outputs separately so that they can be mixed down to the stereo pair later. Uncorrectable balancing errors at the recording session are thus eliminated. Some tracks are often combined and re-recorded on a spare track for further mixing and re-recording. Thus some material may be re-recorded three or four times.
Arranging for the impedances presented by a load to be equal to the internal impedance of the generator; this is essential to avoid loss of power. In mikes, the loss results in poorer signal-to-noise ratio. Matching is done by means of a transformer. Where mike impedance is strongly capacitative; e.g., in electrostatic types the output voltage is fed to the grid of a valve and controls the current in an external circuit.
A transformer designed for insertion between two circuits having different impedances to reduce the reflection at the junction and increase the power transferred.
1. Generic term applied to all processing electroforms. 2. Circuit designed to mix or separate electrical signals. 3. A transformer network, in which the outputs of an M-S microphone pair are combined additively and subtractively, to produce left and right output signals for stereo reproduction.
Serial number engraved or embossed on the lacquer or subsequently on the metal parts.
Type of recording tape with a dulled finish to facilitate proper winding, even on open hubs.
The average distance that sound waves travel between successive reflections in an enclosure.
Prefix signifying one million.
A multiple unit that denotes 1 million Ohms.
A unit of pitch; a simple l-kHz tone, 40 dB above a listener's threshold, produces a pitch of 1,000 mels. The pitch of any sound that is judged by the listener to be n times that of a 1-mel tone is denoted as n mels.
Device which can be made to store the value of a signal presented to it.
A meter whose ballistics allow it to closely follow the peaks in a program. Also called a peak program meter.
A decibel-calibrated meter, used to measure sound pressure levels.
A meter calibrated to read volume units.
A prefix that denotes one millionth.
A unit of pressure commonly used in acoustics. One microbar is equal to 1 dyne per cm2.
A groove of which the unmodulated width at the top is less than 0076 mm and which is intended to be played with a stylus having a tip radius less than 0025 mm.
One millionth of a meter.
An electro-acoustical transducer operating from an acoustical system to an electrical system.
A microphone with a bi-directional polar pattern. See Polar Pattern, Bi-directional.
A microphone in which the diaphragm is one plate of a capacitor.
A microphone with a cardioid polar pattern. See Polar Pattern, Cardioid.
Two or more microphones on the same vertical axis. A stereo microphone.
The popular name for a capacitor microphone.
A microphone with two diaphragms. The second diaphragm may be electronically combined with the first to produce more than one polar pattern. In another type of dual diaphragm microphone, the two diaphragms are for high and low frequencies.
A microphone with two switchable polar patterns.
A moving coil or ribbon microphone.
A microphone with a permanently charged capacitor/diaphragm .
A capacitor microphone.
A microphone with a bi-directional polar pattern. See Polar Pattern, Bi-directional.
A microphone with a hyper-cardioid polar pattern. See Polar Pattern, Hyper-cardioid.
The nominal load impedance for a mike indicates the optimum matching load which utilizes the mike's characteristics to the fullest extent. Impedance is a combination of de resistance, inductance and capacitance, which act as resistances in ac circuits. An inductive impedance increases with frequency; a capacitative impedance decreases with frequency. Either type introduces change in phase.
On a recording console, a two position switch which allows any input module to be assigned to a microphone in the studio, or to a previously recorded track on a tape recorder.
A microphone designed to be worn on a cord around the neck. Primarily used for announcers, talk shows, etc.
Any line between a microphone and the first stage of amplification.
A highly directional microphone.
A microphone in which the diaphragm is attached to a voice coil, suspended in a magnetic field.
A microphone with more than two switchable polar patterns.
A microphone with an omni-directional polar pattern. See Polar Pattern, Omni-directional.
A microphone whose directional characteristics are the result of acoustic phase shifts within the microphone. A uni-directional microphone.
In a recording console, the first stage of amplification, which raises microphone levels to line level. Also, the amplifier built into a condenser microphone.
A microphone that responds to instantaneous variations in air pressure, caused by the sound wave in the vicinity of the microphone. An omni-directional microphone.
A microphone that responds to the difference in acoustic pressure between the front and rear of the diaphragm. A bi-directional microphone.
A microphone in which the diaphragm is a ribbon.
A highly directional microphone, so-called because of its characteristic appearance.
A microphone with two separate transducing systems, built into one housing. The two outputs are kept separate, and are fed to two separate tracks on the tape recorder.
A microphone with a supercardioid polar pattern. See Polar Pattern, Super-cardioid.
A microphone with an ultra-directional polar pattern. See Polar Pattern, Ultra-directional.
A microphone with a unidirectional polar pattern. See Polar Pattern; Uni-directional.
One thousandth of an inch.
A prefix that denotes one thousandth.
Combining electrically the signals from microphones, tape, and reproducers and other sources.
A recording session, during which the many sepajrate tracks of information on a multi-track tape are processed and combined (that is, mixed down) to form a two or four track program, which is then recorded on a second machine.
An apparatus by means of which the outputs of several channels can be faded up and down independently, selected individually, or combined at any desired relative volumes.
A blend of two or more electrical signals or acoustic waves.
The process by which the essential characteristics of a signal wave (the modulating wave) are impressed upon another wave (the carrier wave).
In a recording and reproducing system. That part of the total noise which varies with signal amplitude.
The perception of sound by stimulation of a single ear.
1. (Verb.) To check the technical quality of a transmission. 2. (Noun.) An apparatus for comparing the technical quality of a program at one point in the transmission chain with that of the same program at another point and for giving an alarm if there is any significant difference between the two.
A recording and reproduction system in which all program material is processed in one channel.
A speaker that provides the full spectrum of audio frequencies.
Electroform produced from the Master. Impressions are made from the master disc by a plating process. Up to four mother discs can be produced, but for top quality only two are made. These are positive so cannot be used to make pressings, but they can be played. The next step is to produce the stampers.
On a tape recorder, a system which prevents tape damage when the play button is depressed while the machine is in either rewind or fast forward. The motion sensing system brings the tape to a complete stop before going into the play mode.
Of a microphone, loudspeaker etc. Depending for its action on the movement of a coil in a magnetic field.
Also termed a dynamic speaker. A speaker in which the moving diaphragm is attached to a coil, which is driven by audio frequency currents. These currents interact with a fixed magnetic field and cause the diaphragm to vibrate in unison.
Abbreviation for multiplex.
Magnetic Recording Instruments Association.
The practice of using many close up microphones, as opposed to a coincident pair, or similar stereo pickup.
Circuit in which information from many sources is switched in a defined order to be sent to a single destination.
A system of broadcasting in which two or more separate channels are transmitted on one FM carrier, as in stereophonic broadcasting.
Referring to a tape recorder, recording console, etc., in which there are more than two tracks of recorded information. Generally, Multi-Track implies eight or more tracks.
A multi-track session tape prepared for mix-down.
A relaxation oscillator, usually developing a semi square wave form. Sub classifications include the astable, monostable, and bistable types.
A silencing process or action.