A term which describes digital recording systems that allow any parts of the recording to be played back in any order with no gaps. Conventional tape is referred to as linear, because the material can only play back in the order in which it was recorded.

An addition to the basic MIDI spec that allows Controllers 98 and 99 to be used to control non-standard parameters relating to particular models of synthesizer. This is an alternative to using System Exclusive data to achieve the same ends, though NRPNs tend to be used mostly by Yamaha and Roland instruments.

A system using spectrally-shaped dither to improve the perceived signal-to-noise performance of a digital audio system.

A system for reducing analogue tape noise or for reducing the level of hiss present in a recording. (See DBX and Dolby).

(Nearfield) The acoustic zone close to a sound source or microphone. Often used to describe a loudspeaker system designed to be used close to the listener – although some people prefer the term 'close field'. The advantage is that the listener hears more of the direct sound from the speakers and less of the reflected sound from the room.

A means of arranging two or more directional microphone capsules such that they receive sound waves from the directions or interest at slightly different times due to their physical spacing. Information about the directions of sound sources is captured in the form of both level differences between the capsule outputs, generated by aiming directional polar patterns in different directions, and the timing differences caused by their physical spacing. Specific forms of near-coincident microphones include the ORTF and NOS arrangements.

the physical angle between two microphones, used to specify various microphone array configurations (eg. 90 degrees for a Blumlein pair, or 110 degrees for an ORTF array).

A recording device capable of recording several 'parallel' parts or tracks which may then be mixed or re-recorded independently.

A synthesizer, sampler or module that can play several parts or different sounds at the same time, each under the control of a different MIDI channel.

The creation of several samples, each covering a limited musical range, the idea being to produce a more natural range of sounds across the range of the instrument being sampled. For example, a piano may need to be sampled every two or three semitones in order to sound convincing.