gain. Amplification applied to a signal, expressed in decibels.

gain before feedback. The maximum volume level a sound system can attain before microphones begin feeding back.

gain factor. A measure of the amount of gain a vacuum tube can produce. See also 12ax7, 12at7, 12ay7.

gain range. The amount of gain available in a preamp.

gain reduction. The attenuation of a signal’s peak levels using a compressor or limiter.

gain stage. A point in a circuit or device where the gain or level of a signal can be amplified, or where level can be controlled/adjusted.

gain staging. Setting up and managing the gain or level of a signal at various points in a signal path for optimum performance. Gain staging includes setting up each stage so that no single stage is providing all or most of the amplification, managing headroom and signal-to-noise, managing levels so that all faders and controls are at reasonable points (none are turned all the way up, and none are turned all the way down), all meters are showing safe levels, digital devices are receiving enough signal for good resolution, and so on.

gain structure. See gain staging.

GAS. Gear Acquisition Syndrome or Guitar Acquisition Syndrome (depending on who is suffering from the affliction). The burning need to acquire a piece of equipment or to own the latest and greatest models.

gate. See noise gate.

Gauss. A measure of magnetic flux. Named for German mathematician Karl Gauss.

GB. See gigabyte.

General MIDI (a.k.a. GM). A standard developed to make it easy to transfer a MIDI song from one system to another while providing consistent performance. A GM-compatible synthesizer must adhere to a variety of requirements, such as providing a standardized set of 128 presets that are stored in a certain order (for example, Patch 1 is always a piano), 24 notes of polyphony, a number of specifically defined continuous controller as signments, and so on.

General MIDI Lite (a.k.a. GM Lite). A version of the General MIDI standard designed to work with cell phones and handheld devices. The polyphony requirement is reduced to 16 notes, the GM preset set is used, and seven continuous controllers are specified.

General MIDI 2 (a.k.a. GM2). An extension of General MIDI that ups the polyphony requirement to 32 notes. The standard patch set requirement is upped to 256, more controllers are specified, and backward-compatibility with GM is required.

generational loss. An analog tape phenomenon in which audio quality is lost with each additional generation of signal that is recorded or added. (In most cases, high frequencies are lost and noise builds up.) Examples of when generational loss occurs include when one analog tape is copied to another, or when overdubs are accomplished by bouncing between two analog tape decks.

genlock. The process of locking a device to a synchronization generator or clock.

GHz. See gigahertz.

gig. 1. Short for gigabyte. 2. A “job” in musician-speak.

gigabit. One billion bits, or 1,000 Mb. Gigabit is also used to refer to a transmission speed of one billion bits per second, or 1,000 Mbps, such as is provided by gigabit Ethernet.

gigabyte (a.k.a. GB). One billion bytes, or 1,000 MB.

gigahertz. A frequency of one billion Hertz. Gigahertz is used as a unit of measure for computer clock speeds, for ultra-high-frequency radio signals (UHF), and for other extremely high-frequency signals.

glass master. A step in manufacturing compact discs, where the audio data is written using a laser onto a glass plate covered with photoresist coating. The plate is then used as a mold for creating the metal data layer for the final compact discs.

glide (a.k.a. glissando, portamento). A synthesizer function that smoothly changes the pitch from one note to the next with no break in the sound.

gliss. See glissando.

glissando. A slide between pitches; how this is accomplished varies from instrument to instrument.

glitch. 1. See stutter effect. 2. A sudden malfunction or error. 3. A short unwanted noise or other audio artifact. 4. An unexpected setback. 5. A genre of experimental electronic music based around short sampled sounds and noises used to create beats.

global. Parameters that affect a device as a whole, as opposed to more specific parameters that may affect only a particular function or preset.

GM. See General MIDI.

GM2. See General MIDI 2.

gobo. Short for “go-between.” A movable divider or barrier used in a studio to isolate one instrument from another to help reduce bleed.

gold sputtered. A type of microphone diaphragm made from Mylar covered with an extremely thin—molecule thin—layer of gold. The gold provides conductivity, yet is light enough and thin enough not to impede the motion of the diaphragm in response to sound waves.

Golden Mean. A ratio of 0.618, which, when applied to room dimensions, is believed by some to provide the ideal spacing of room modes across the frequency response of the space. In practice, this works out to the width being 1.6 times the height, and the length being 2.6 times the height.

Golden Ratio. See Golden Mean.

goniometer. See jellyfish meter.

gooseneck. A flexible metal extension that can be added between a mic stand and a microphone adapter. A gooseneck allows the microphone to be easily repositioned in any direction. Some manufacturers coat the gooseneck with rubber or other materials to cut down on noise created when the microphone is moved.

GPI. General Purpose Interface. A hardware device featuring switches or other functions that can be controlled using MIDI or SMPTE and that can be used to control a function in a non-MIDI-compatible piece of hardware.

GPU. Graphics Processing Unit, a.k.a. Graphics Accelerator. A graphics component in a computer that is optimized to assist with processing video data for the computer’s display.

graded hammer action (a.k.a. progressive hammer action). A type of weighted keyboard action whose response varies with position on the keyboard. Typically, the higher notes have a lighter feel than the bass notes, simulating an acoustic grand piano key action.

granular synthesis. A type of digital additive synthesis that uses very short sounds called grains, which can be combined and processed in a variety of ways. Granular synthesis can create complex sounds, but it requires a powerful computer.

graphic equalizer. A type of audio equalizer with a separate level control (usually a slider) for each of a number of frequency bands. The name “graphic” EQ comes from the fact that the curve or arrangement of the control sliders is visually analogous to the response of the unit. Standard sizes/formats include 15 bands per channel (where each band covers 2/3 octave) and 30 or 31 bands per channel (where each band covers 1/3 octave). Graphics equalizers are easy to use but do not provide the flexibility and precision required for many studio tasks. Graphic EQs are often used to shape the sound of live sound systems and to control feedback in stage monitor systems. See Figure G.1.

Figure G.1. A type of equalizer that has a slider for the level of each band of frequencies, but that does not allow control over bandwidth or frequency center, is called a graphic equalizer.

graphical user interface (a.k.a. GUI). A computer operating system in which the user interacts with the computer by responding to and manipulating graphic elements, such as icons, menus, switches, knobs, and other items, many of which are analogous to real, physical items. For example, a graphical user interface might allow the user to store data in a folder on the screen, which functions in the same way a real folder does for storing papers. See Figure G.2.

Figure G.2. A computer’s GUI, or graphical user interface, consists of a variety of elements, such as icons, menus, switches, control panels, knobs and other controls, folders, and more.

Green Book. One of a set of “Rainbow Books” with colored covers containing the Sony/Philips-developed specifications for different optical compact disc formats. The Green Book contains the specification for CD-Interactive or CD-I.

grid. An electrode in a vacuum tube that controls the flow of electrons.

grid mode. A MIDI and audio editing mode found in some DAWs where data is locked to a grid representing rhythmic divisions, such as eighth notes, sixteenth notes, sixteenth-note triplets, and so on; all new data or edited data snaps to the nearest grid location and conforms automatically to the preset rhythmic value of the grid. This can make it very easy to add data or to edit drum parts without messing up the rhythms.

grille. The acoustically transparent front panel of a speaker or guitar or bass combo amplifier. The grille is intended to protect the speaker drivers from damage, as well as to provide a visually attractive look for the front of the unit.

grille cloth. Acoustically transparent fabric used to protect and conceal drivers in a speaker cabinet.

groove. 1. A rhythmic pattern in which the rhythm has been performed or manipulated in such a way as to have a particular “feel.” This may involve pushing/pulling certain beats, shortening or lengthening certain time intervals or rhythms within the larger rhythm, or delaying or rushing certain beats to create a specific effect. 2. The continuous spiral on a vinyl LP record that contains a representation of the audio data. There is only one groove on a record, which begins at the outside and spirals toward the center of the LP.

groove quantize. A function found in sequencers and DAWs that quantizes a MIDI track or selected MIDI data on a track to match the rhythmic feel of another MIDI performance—another track, a preprogrammed rhythm, a MIDI loop, or other rhythmic material.

ground (a.k.a. earth). The zero reference for voltage in a circuit or device (typically connected eventually to the actual earth or ground). Voltage on a “hot” conductor is measured against ground, which is at zero potential or volts.

ground lift. 1. A method or device—often a switch on a device—that disconnects a signal’s connection to ground in order to prevent ground loops or hum. 2. A 3-to-2 prong AC adapter that removes the connection to an AC outlet’s ground conductor. These adapters are never a good idea ... don’t use them!

ground loop. A situation in which a system or signal has multiple paths to ground available at once. This results in 60-cycle hum; the intensity of the hum depends on the particular ground loop situation in a system.

group. A number of faders or channels on a mixer (whether hardware or software) that have been linked together so they can be controlled by a movement of any one of the faders or channel controls. Different mixers will allow different controls to be grouped; some only support faders, other add support for pan, still others might allow grouping of other controls, such as solo, mute, and others. The faders and controls in a group will usually move relative to one another so that the relative position of each control stays the same compared to the other controls. See also fader group.

group delay. The time it takes for a signal to pass through a circuit, referenced or plotted against frequency. In a filter, some frequencies may be delayed slight more than other frequencies, resulting in phase distortion within the signal being filtered.

GSIF. GigaSampler Interface. A driver that supports streaming of samples from a hard drive so that longer samples can be played than will fit in a sampler’s or computer’s RAM or that can be efficiently handled from within RAM. Named for GigaSampler, one of the first software samplers, and the first to offer streaming of samples from a hard drive—GigaSampler was developed by NemeSys Music and later acquired and eventually discontinued by TASCAM.

guard band. A blank track on an analog tape between a track used for time code and the next track used for audio. The guard band prevents the time code signal from bleeding into the audio track.

GUI. See graphical user interface.

guide track. See scratch track.

guide vocal. See scratch vocal.