Principal axis

3-1-135

Principal axis (of a sound source or receiver)

Generally the axis of structural symmetry or the direction of maximum emission or response.

Reference direction serving as an origin for angular co-ordinates used in describing the directional characteristics of the sound source or receiver.

Reference: I.E.C. (modified)

Please note that this is the term as it stands in the original IALA Dictionary edition (1970-1989)

English