(19)

(11)

EP 0 636 287 A1

(12)

(43) Date of publication: 01.02.1995 Bulletin 1995/05 (21) Application number: 92916034.0 (22) Date of filing: 15.04.1992

(51) International Patent Classification (IPC):  G10K 11/ 178( . ) (86) International application number: PCT/US1992/003024 (87) International publication number: WO 1993/021687 (28.10.1993 Gazette 1993/26)

(84) Designated Contracting States: AT BE CH DE DK ES FR GB GR IT LI LU MC NL SE (71) Applicant: NOISE CANCELLATION TECHNOLOGIES, INC. Linthicum, MD 21090 (US)	(72) Inventor: LANGLEY, Andrew Welwyn, Herts ALG OQD (GB) (74) Representative: Dauster, Hanjörg, Dipl.-Ing.  WILHELM & DAUSTER Patentanwälte Hospitalstrasse 8 D-70174 Stuttgart D-70174 Stuttgart (DE)