Phonometric Chamber

a specially equipped room for acoustic measurements. There are two basic types, the anechoic chamber, for measuring the fundamental characteristics of electroacoustic apparatus under conditions equivalent to those of free space (microphones, loudspeakers, and other sound receivers and radiators), and the reverberation chamber (resonant phonometric chamber), for measuring the sound absorption of various materials, structures, and objects, as well as the acoustic power of sound sources in a diffuse soundfield.