BSS Audio FDS 360, Руководство пользователя

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Any modification of a signal which produces new frequency components not
presents in the original. Harmonic distortion refers to added frequencies that
are overtones to the fundamental frequency. Intermodulation distortion refers
to added frequencies that are sum and difference values derived from the
beating together of two frequencies.
Distortion
Modification of the frequency response of an audio system, regardless of
level, for corrective or enhancement purposes.
Equalisation
The repetition of a waveform. The unit of frequency is Hz, and 1 cycle per
second is equal to 1Hz. The audio band is generally restricted to frequencies
of 20Hz to 20,000Hz (20kHz).
Frequency
The equipment's relative gain compared to frequency. Generally expressed as
+/- a certain number of dBs from 20Hz to 20kHz.
Frequency
Response
The amount, in dBs, by which a compressor/limiters output has been reduced
in level with respect to its uncompressed level.
Gain Reduction
The amount, in dBs, above the normal operating level that can be used before
serious distortion commences.
Headroom
Impedance The AC equivalent of resistance and measured in ohms. It indicates the
amount of drive required for an input, or the drive capability of an output, at a
given signal level.
The amplitude of a signal, measured in Volts or Decibels.
Level
Generally indicates a signal whose level is between -10 and +10dBu or -14 to
+6 dBV. Mic level refers to levels around -40dBu.
Line Level
Similar to a compressor but harder acting, and generally used as a protection
device for audio systems.
Limiter
A logarithmic unit for expressing frequency ratios. Positive values indicate an
increase and negative ones a decrease. One octave 'up' the scale is
equivalent to double the frequency. One octave 'down' is equivalent to half
the frequency.
Octave
The relationship between change in input level and resulting change in output
as a consequence of compressing or limiting.
Ratio
Release Time The time required for a compressor or limiter to restore its gain to normal, after
the input signal has fallen below threshold.
The pre-settable level above which a compressor or limiter will commence to
gain reduce.
Threshold