Glossary - SoundCraft MFX User Manual

GLOSSARY

AFL
Auxiliary send
Balance
Balanced
Clipping
DAT
dB (decibel)
DI(direct injection)/DI Box
Equaliser
Fader
Feedback
Foldback
Frequency response The variation in gain of a device with frequency.
Gain
Headroom
Impedance balancing A technique used on unbalanced outputs to minimise the effect of hum and interfer-
Insert
Pan (pot)
Peaking
Peak LED
PFL
Phase
Polarity
Post-fade
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After-fade listen: a function that allows the operator to monitor the post-fade signal in
a channel independently of the main mix.
An output from the console comprising a mix of signals from channels derived inde-
pendently of the main stereo mix.
The relative levels of the left and right channels of a stereo signal.
A method of audio connection which 'balances' the wanted signal between two wires,
these wires also have a screen which carries no signal. Any interference is picked up
equally by the two wires, which results in cancellation of the unwanted signal. In this
guide, the term can refer to various circuit architectures. Connection details are given
in relevant sections.
The onset of severe distortion in the signal path, usually caused by the peak signal
voltage being limited by the circuit's power supply voltage.
Digital Audio Tape, a cassette-based digital recording format.
A ratio of two voltages or signal levels, expressed by the equation dB=20Log10 (V1/
V2). Adding the suffix 'u' denotes the ratio is relative to 0.775V RMS.
The practice of connecting an electric musical instrument directly to the
input of the mixing console, rather than to an amplifier and loudspeaker which is
covered by a microphone feeding the console.
A device that allows the boosting or cutting of selected bands of frequencies in the
signal path.
A linear control providing level adjustment.
The `howling' sound caused by bringing a microphone too close to a loudspeaker
driven from its amplified signal.
A feed sent back to the artistes via loudspeakers or headphones to enable them to
monitor the sounds they are producing.
The amount of amplication in level of the signal.
The available signal range above the nominal level before clipping occurs.
ence when connecting to external balanced inputs.
A break point in the signal path to allow the connection of external devices, for in-
stance signal processors or other mixers at line level signals. Nominal levels can be
anywhere between 0dBu to +6dBu, usually coming from a low impedance source.
Abbreviation of 'panorama': controls the levels sent to left and right outputs.
The point at which a signal rises to its maximum instantaneous level, before falling
back down again. It can also describe an equaliser response curve affecting only a
band of frequencies, (like on a graphic equaliser), "peaking" at the centre of that
band.
A visual indication of the signal peaking just before the onset of clipping, which will
distort the signal.
Pre-fade listen: a function that allows the operator to monitor the pre-fade signal in a
channel independently of the main mix.
A term used to describe the relationship of two audio signals. In-phase signals rein-
force each other, out-of-phase signals result in cancellation. Phase is a measurement
of relative displacement between two waves of identical frequency.
A term used to describe the orientation of the positive and negative poles of an audio
connection. Normally connections are made with positive to positive, negative to
negative. If this is reversed, the result will be out-of-phase signals (see 'phase' above).
The point in the signal path after a fader and therefore affected by the fader position.