(19)
(11) EP 0 323 830 A3

(12) EUROPEAN PATENT APPLICATION

(88) Date of publication A3:
24.07.1991 Bulletin 1991/30

(43) Date of publication A2:
12.07.1989 Bulletin 1989/28

(21) Application number: 89100047.3

(22) Date of filing: 03.01.1989
(51) International Patent Classification (IPC)4: H04S 3/00
(84) Designated Contracting States:
AT BE CH DE ES FR GB GR IT LI LU NL SE

(30) Priority: 06.01.1988 US 141570

(71) Applicant: LucasArts Entertainment Company
Nicasio, CA 94946 (US)

(72) Inventor:
  • Holman, Tomlinson
    Fairfax, Cal. 94930 (US)

(74) Representative: Hoffmann, Eckart, Dipl.-Ing. et al
Patentanwalt, Bahnhofstrasse 103
82166 Gräfelfing
82166 Gräfelfing (DE)


(56) References cited: : 
   
       


    (54) Surround-sound system


    (57) Spectral imbalance (alteration in timbre) when playing home video versions of motion pictures is overcome by re-equalization according to a unique correction response curve which compensates for the equalization for playback in large theater-sized auditoriums inherent in motion picture soundtracks. Surround-sound home playback of motion pictures is enhanced by employing main channel loudspeakers that produce generally direct sound fields and surround channel loudspeakers that produce generally diffuse sound fields. Preferably, further equalization is applied to the reproduced surround channel to compensate for the differences in perceived timbre between direct and diffuse sound fields. In addition, the reproduced surround-sound channel is further enhanced by decreasing the interaural cross-correlation of the surround-sound channel sound field at listening positions within the room, preferably by introducing slight pitch shifting in the signals applied to multiple surround loudspeakers.







    Search report