Audio system measurements

Audio system measurements are made for several purposes. Designers take measurements so that they can specify the performance of a piece of equipment. Maintenance engineers make them to ensure equipment is still working to specification, or to ensure that the cumulative defects of an audio path are within limits considered acceptable. Some aspects of measurement and specification relate only to intended usage. For example, magnetic tape speeds and types, interface specifications, or power output.

Others are intended as an index of the quality, or 'fidelity', of reproduction perceivable by a human. It is important that such measurements accommodate psychoacoustic principles, so that they truly measure the system in a way that is 'subjectively valid'.