Gain
In audio jargon the term is equivalent to level. For filters, describes the degree of boost/cut in dB.

General MIDI (GM)
A set of requirements for MIDI devices aimed at ensuring consistent playback performance on all instruments bearing the GM logo. Some of the requirements include 24-voice polyphony and a standardized group (and location) of sounds.
For example, patch #17 will always be a drawbar organ sound on all General MIDI instruments.

Glide
A function, also called portamento, in which the pitch slides smoothly from one note to the next instead of jumping over the intervening pitches.

Graphic Equalizer
A type of equalizer that provides control over a fixed set of frequencies. Each filter provides linear cut/boost control over a fixed frequency. The number of filters on graphic equalizers range from three (low, mid, high) to well over eleven. While graphic equalizers generally have more filters than parametric equalizers, they are less flexible, in that the individual filter frequencies are not adjustable.

graphic editing
A method of editing parameter values using graphic representations (for example, of envelope shapes) displayed on a computer screen or LCD.