This International Standard applies to directional loudspeaker array systems of any kind, and to the parts of which they are composed or which are used as auxiliaries to such system. T his standard deals with the determination of the performance of directional loudspeaker array systems, the comparison of these system types, and the determination of their proper practical application, by listing the characteristics which are useful for their specification and laying down uniform methods of measurements for these characteristics. This standard is confined to a description of audio space around a person and the relevant method of measurement; it does not in general specify characteristics of loudspeakers, which are explained in IEC 60268-5.