A disc for mechanical or electromechanical recording usually made of metal, glass or fiber and coated with lacquer compound. It may be coated on one side (single-sided) or both (double sided).
The uncut surface between adjacent grooves.
A mechanical or electromechanical recording in which the groove modulation is perpendicular to the motion of the recording medium and parallel to its surface.
The length of plain groove that starts at the periphery of the record and the pitch of which is greater than normal recording pitch.
The length of plain groove which succeeds the recorded surface and the pitch of which is greater than the normal recording pitch.
Uncoated tape, usually white, spliced to the beginning of a recording tape. Non-magnetic tape, spliced between segments of magnetic tape, to visually indicate the beginning and end of recorded segments.
Extraneous sounds, picked up by a microphone. Generally used to describe the unwanted sound of one musical instrument as heard by a microphone in front of another instrument.
The transmission of sound, from a headphone to a nearby microphone.
Intensity of a continuous tone used for test purposes (measured in decibels by comparison with the standard reference level, or zero level, of 0775 volt rms, which is equivalent to a power of 1 milliwatt in a resistance of 600 ohms); colloquially, intensity of program output or of noise.
Any circuit that converts an audio signal into a control voltage, which may be used to regulate the operating parameters of a signal processing device.
Device for automatically limiting the volume during program peaks so as to prevent accidental overmodulation of a transmitter or overloading of other equipment. (As the volume applied to the input of the limiter increases, the volume at the output increases linearly up to a certain critical point, after which a further increase in input volume produces a much smaller increase in output volume. When the applied volume exceeds the critical value, the device necessarily introduces amplitude distortion, but ought not to introduce excessive non-linear distortion.) Unlike the compressor, there is no slope or gradual attenuation in a limiter. A somewhat higher recording level can therefore be used without fear of a peak overloading the tape. Limiters and compressors are often used together. Generally, a limiter is a compressor with a compression ratio of 10:1 or greater.
A transmission line, or, any signal path.
A transmission line with a characteristic impedance of 600 ohms.
A signal whose level is at, or about, +4 dBm.
An impedance matching transformer, used to match the impedance of one line to another.
An attenuation network, designed for insertion in a line.
Locus of displacement resulting from two signals applied at right angles. The form of ellipse obtained indicates relative phase.
1. Performance broadcast or recorded at the time of its performance to an audience (as distinct from a studio recording). 2. Studio having a comparatively long reverberation time, and therefore tending to give a brilliant acoustic effect. 3. Connected to electrically sensitive part of a circuit.
A resistor placed across a line to meet impedance matching requirements. A resistor placed across the output terminals of an amplifier for testing purposes. The resistor takes the place of the normal load.
Placing a load across a line. Often used to describe the effect on a circuit of a load that is equal to, or less than, the characteristic impedance of the line to which it is connected.
A logarithm.
The logarithm of a number is that power to which 10 must be raised to equal the number. The logarithm of 1,000 is 3, since 10 to the 3rd power = 1,000.
Scale of measurement in which an increase of one unit represents a tenfold increase in the quantity measured.
The side and rear protrusions on some uni-directional polar patterns, denoting slight sensitivity increases at various off-axis angles. The front and rear segments of a bi-directional polar pattern.
An observer's auditory impression of the strength of a sound.
An electroacoustic transducer operating from an electrical system to an acoustical system and designed to radiate sound.
an electrostatic loudspeaker.
an electrostatic loudspeaker.
The diaphragm of a moving coil loudspeaker.
The moving membrane in a loudspeaker.
Equivalent term for crossover network.
A moving coil or ribbon loudspeaker.
A loudspeaker in which the diaphragm is one plate of a capacitor.
Equivalent term for speaker impedance.
A loudspeaker in which the diaphragm is attached to a voice coil suspended in a magnetic field.
A loudspeaker in which the diaphragm is a ribbon.
Equivalent term for speaker system.
The moving coil to which the loudspeaker diaphragm is attached.
The grille of a speaker.
