Peripheral Component Interconnect: an internal computer bus format used to integrating hardware devices such as sound cards. The PCI Local Bus has superseded earlier internal bus systems such as ISA and VESA, and although still very common on contemporary motherboards has, itself, now been superseded by faster interfaces such as PCI-X and PCI Express.

A short cable used with patch bays.

A system of panel-mounted connectors used to bring inputs and outputs to a central point from where they can be routed using plug-in patch cords. Also called a Jackfield.

An alternative term for a Program, referring to a single programmed sound within a synthesizer that can be called up using Program Change commands. MIDI effects units and samplers also have patches. (see also Bank)

A loudspeaker which requires an external power amplifier, the signal from which is passed to a passive cross-over filter. This splits and filters the signal to feed the two (or more) drive units.

A circuit with no active elements.

The combination of fundamental and overtones together are called particals. (cf. harmonic)

Often used to descibe a multi-oscillator mono-synth which can be configured to allow the oscillators to be controlled independently from the keyboard, allowing two or more notes to be played simultaneously.

An equaliser with a bell-shaped frequency response curve, and separate controls for the centre frequency, the bandwidth (Q), and the amount of cut/boost. If a bell EQ omits the bandwidth (Q) control, it is known as semei- or quasi-paramteric.

A variable value that affects some aspect of a device's performance.