feedback the ‘howling’ sound caused by bringing a microphone
too close to a loudspeaker driven from its amplified signal.
foldback a feed sent back to the artistes via loudspeakers or
headphon es to ena b le them to monitor the sound s they are
producing.
frequency response the v ariat ion in gain of a de vice w ith fr eque ncy.
(sub) group an output into w hich a group of signals can be mixed.
headroom the available signal range above the nominal level
before clipping occurs.
highpass filter a filter th at rejects low frequ encies.
line level signals at a n omin al lev el of -10 to + 6dBu, u sua lly com ing fr om a low
impe dan ce sour ce.
mono output a mono sum of the left/ right mix outp uts, providing a
separ ately con trolled line lev el feed for add itiona l
loud speak ers.
pan (pot) abbre v iation of ’pano rama ’: controls lev els sent to left
and right outp uts.
peaking an equaliser resp onse curve affecting only a b and of
frequencies i.e. based on a ban dpass resp onse.
PFL (pre-fade listen) a function that allows the operator to m onitor the pre-fade
signal in a channel independently of the main mix.
rolloff a fall in gain at the extremes of the frequency response.
shelving an equaliser response affecting all frequencies above o r
below the break frequ ency i.e. a highpass or low pass derived
response.
spill acoustic interference from other sources.
talkback the operator speaking to the artistes or to tape via the
auxiliary or group outpu ts.
transien t a momentary rise in the signal level.
+48V the phantom pow er supply, available at the channel mic
inputs, for condenser microphones and active DI boxes.
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