ASA 128th Meeting - Austin, Texas - 1994 Nov 28 .. Dec 02

3aPP10. Personal sound.

W. F. Druyvesteyn

R. M. Aarts

Philips Res. Labs., Bldg. WAK, P.O. Box 80000, 5600 JA Eindhoven, The Netherlands

Introducing more audio/video equipment (CD, DCC, TV, CD-I, etc.) into a room creates a new audio problem, one of multiple sound sources with multiple listeners. When different persons, denoted as A, B, C, etc., listen to different programs, denoted as ``a,'' ``b,'' ``c,'' person A experiences program ``a'' as sound and programs ``b'' and ``c'' as noise. Each person would prefer a high sound/noise (S/N) ratio at his listening position. In this contribution the situation of two persons working with their (multimedia) PCs in an office, or watching in a living room two TVs with accompanying sound, is considered. In order to obtain a specification, listening tests were done, which gave a desired S/N ratio of about 20 dB(B). In an anechoic environment such a specification is easily realized using a loudspeaker array to control the directivity. In a real (living) room this is not sufficient and active noise control (to decrease N) and active sound control (to increase S) are used, particularly in the low-frequency region. During the presentation at the conference, recordings will be reproduced of realized S/N ratios of 34 dB(B) in the anechoic room and of more than 20 dB(B) in a living room.