(19)

(11)

EP 0 716 800 A1

(12)

(43) Date of publication: 19.06.1996 Bulletin 1996/25 (21) Application number: 94928555.0 (22) Date of filing: 31.08.1994

(51) International Patent Classification (IPC):  H04R 25/ 00( . ) (86) International application number: PCT/US1994/009931 (87) International publication number: WO 1995/007014 (09.03.1995 Gazette 1995/11)

(84) Designated Contracting States: DE DK GB NL (30) Priority: 01.09.1993 US 19930114898 (71) Applicant: KNOWLES ELECTRONICS, INC. Itasca, Illinois 60143 (US)	(72) Inventor: MOSTARDO, August, F. Norridge, IL 60656 (US) (74) Representative: Dunlop, Brian Kenneth Charles, et al  c/o Wynne-Jones, Lainé & James 22 Rodney Road Cheltenham Gloucestershire GL50 1JJ Cheltenham Gloucestershire GL50 1JJ (GB)