FREE-FIELD RESPONSE OF SOUND LEVEL METERS.

When measuring the directional and frequency response characteristics of sound level meters, the far field reflections from the walls of the anechoic chamber as well as the near field reflections from the sound level meter body and the supporting structure are the inevitable. In this article the use of warble tones, instead of pure tones, shows how the far field reflections are eliminated and how the reflections from the sound level meter body affect the directional and frequency characteristics.