The nominal output voltage generated by a microphone for a known reference acoustic sound pressure level. Output sensitivity is normally specified for a sound pressure level of one Pascal (94dB SPL), and may range from about 0.5mV/Pa for a ribbon microphone, to 1.5mV/Pa for a moving coil, and up to 20 or 30mV/Pa for a capacitor microphone.

The effective internal impedance (resistance which many change with signal frequency) of an electronic device. In modern audio equipment the output impedance is normally very low. Microphones are normally specified with an output impedance of 150 or 200 ohms, although some vintage designs might be as low as 30 Ohms.

see Polarity.

A circuit designed to generate a periodic electrical waveform.

An abbreviation for 'oscillator' or 'Open Sound Control'.

A specific form of near-coincident microphone array devised by the Office de Radiodiffusion Télévision Française (ORTF) at Radio France, the French national broadcaster. The technique employs a pair of small-diaphragm cardioid microphones mounted with a mutual angle of 110 degrees and spaced apart by 17cm. The theoretical stereo recording angle is 96 degrees.

– A device where some electrical parameter changes in response to a variation in light intensity. For example, variable photo-resistors are sometimes used as gain control elements in compressors where the side-chain signal modulates the light intensity.

The concept of configuring a computer in such as way as to maximise its performance for certain tasks. In the context of a machine being used as a DAW, optimisation might involve disabling sub-programs that access the internet regularly or intermittently, such as email hosts, automatic program update checkers and so on. It might also include the structure of the hard drive, or the separation of program data to a system drive and audio data to a separate drive to minimise access times and maximise data throughputs.

The basic software that enables a computer to load and run other programs.

A high-resolution networked communication protocol for computers, synthesizers and other audio devices.