Acoustic environment for audio teleconferencing
R. Betres · The Journal of the Acoustical Society of America · 1976
In contrast to handset telephony, the acoustic environment plays an important role in handsfree (loudspeaking) telephony and more significantly in audio teleconferencing. With increasing distance between talker and telephone terminal, the effects of room resonances, reverberence and background noise on the quality of speech telecommunication became more and more critical. The range of variation of these parameters in executive offices and conference rooms was investigated in this survey. The results indicate a common shortcoming in most of these locations: a sound-absorbing ceiling and hard, parallel walls. The effectiveness of directional microphones in improving the situation was subjectively tested in simulated environments. The results give an indication of the limits of acceptability of the acoustic environment. A weighting system for ranking the audio quality of a conference room is proposed, taking into consideration the above mentioned factors and results. [Work supported by Bell Canada.]