This is the name given to the amplification of a signal level. It can be expressed as a ratio of the output signal amplitude to the input signal amplitude. For example, Voltage gain:

Gain = Vout / Vin

Gain is normally expressed in dB.

For voltage gain use:

Gain (dB) = 20 log10 Vout/Vin

For current gain use:

Gain (dB) = 20 log10 Iout/Iin

For power gain use:

Gain (dB) = 10 log10 Vout/Vin

Gain Control
This is a device which adjusts the gain of an amplifier. This is normally done by altering the amount of negative feedback in the amplifying system. A Gain Control is not the same as an ‘attenuator’ or a ‘volume’ control.

Granular Synthesis
This technique uses small segments of either sampled or synthesised sound to generate a new sound or sound texture.

Ground Loop
This is a condition that occurs when two or more paths to ground exist and an unequal voltage is induced in each of the paths causing buzz, hum or other noise.

This is a Mixing Desk channel to which a group of audio signals can be routed to allow the treatment and control of the resulting combined signal.

Guitar Neck
Long, normally wood, section of the guitar that the strings are stretched over.

Guitar Nut
The guitar nut is a strip, between the fret board and headstock, on which the guitar strings sit. The nut normally has small notches which are used as guitar string guides.