This Engineering Bulletin recommends preferred voltage and impedance values for inputs and outputs of generally available, mass produced, audio products and accessories. The purpose of these values is to guide manufacturers in the design of their products so as to facilitate the interconnection of products of different manufacturers.

The values are also intended as a guide for the manufacturers of integrated systems whose equipment has input and output connections which permit the addition of other products or accessories. The values, wherever possible, have been chosen to minimize changes in apparent sound output level when switching functions. The values are also intended to prevent gross inequities between products of different manufacturers that may result in either objectionable distortion due to overload or inability to develop sufficient sound output due to lack of gain.

Accepted industry test methods are to be used and good engineering practice followed in applying these values. Value changes will occur as dictated by advances in technology.

Establishes preferred voltage and impedance values for inputs and outputs of generally available, mass produced, audio products and accessories. These values guide manufacturers in the product design in order to facilitate the interconnection of products of different manufacturers and permit the addition of other products or accessories to integrated systems which have input and output connections.