A compound designed to increase the conductivity of electrical contacts such as plugs, sockets and edge connectors. (cf. De-Oxidising Compound)

An alternative term for mixer (See also Desk).

A specific shape of drive unit diaphragm intended to push and pull the air to create acoustic sound waves. Most bass drivers use cone-shaped diaphragms, where the electromagnetic motor of the drive unit is connected to the point of the cone, and its outer diameter is supported by some form of flexible membrane.

A material that provides a low resistance path for electrical current.

see Capacitor Microphone

A device which can be instructed (or programmed) to carry out arithmetic or logical operations. Although mechanical 'analogue' computers do exist, most are now electronic and digital, and process digital data.

A device (analogue or digital) which is designed to reduce the overall dynamic range of an audio signal either by attenuating the signal if it exceeds a set threshold level according, or by increasing the level of quiet signals below a threshold. The amount of attenuation is defined by a set ratio, while the speed of response (attack) and recovery (release) can usually also be controlled.

An encode-decode device typically employed to pass a wide dynamic range signal over a channel with a lower dynamic range capability. The source signal is compressed in the encoder to reduce the dynamic range, and subsequently expanded by the decoder to restore the original dynamics. The Dolby noise reduction codecs are examples of companders.

Originally conceived as a recording format for dictation machines in the early 1960s, it became a mainstream music release format in the form of the Musicassette. A plastic shell protected 3.81mm wide (1/8-inch) recording tape which ran at 4.75cm/s. A stereo track was recorded in one direction, and the tape could be turned over to play a second stereo track recorded in the opposite direction.

A measure of how well a balanced circuit rejects an interference signal that is common to both sides of the balanced connection.