right meter. This allows the engineer to check the qual- ity of the signal or to
Each input channel and the Group and Mix outputs have an Insert ‘A’ gauge jack socket, which is a break point in the signal path. It allows the signal to be taken out of the mixer, through an external piece of equip- ment and then back into the mixer directly after its original exit point. The Insert point is normally by- passed by the ‘A’ gauge jack socket contacts, and is only brought into operation when a plug is inserted. Typical uses would include Effects Processors, Limiters or additional Equalisers.
The terms PRE and POST are often used in the context of Inserts, Equalisers and Auxiliary Sends, and describe whether that facility is placed before (Pre) or after (Post) another particular section. This is explained further in the detailed description of facilities.
A mixer is often judged, amongst other factors, by the amount of Headroom available. This is a measure of the reserve available to cope with sudden peaks in the input signal, without distortion caused by Clipping, when the signal becomes so high that it would exceed the power supply rail voltages and is as a result limited. This commonly occurs where gain settings are incor-
Clipped
Signal
Noise
If the signal level is too high, clipping distortion may occur.
SignalNoise
If the signal level is too low it may be masked by the noise.
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