EP 0435304 A3 19911023 - ACOUSTIC APPARATUS AND DRIVING APPARATUS CONSTITUTING THE SAME
Title (en)
ACOUSTIC APPARATUS AND DRIVING APPARATUS CONSTITUTING THE SAME
Publication
Application
Priority
JP 33521089 A 19891226
Abstract (en)
[origin: EP0435304A2] An acoustic apparatus comprises a cabinet, and a loudspeaker unit and a driving apparatus disposed in the cabinet. The acoustic apparatus is driven by an external power amplifier which normally constant-voltage-drives a conventional loudspeaker. The driving apparatus has a power amplifier circuit and a transfer function control circuit, and drives the loudspeaker unit in cooperation with the external power amplifier. The driving apparatus generates an electric energy corresponding to an increase in energy from that which is required in a normal constant-voltage-driving, the increase being produced by an operation of the transfer function control circuit, and the generated energy is inputted to the loudspeaker unit. By means of the above, when the acoustic apparatus is driven by the external power amplifier, an internal resistance of the loudspeaker unit is substantially cancelled or reduced, and an improvement of the electro-acoustic transducing characteristics of the loudspeaker unit or a loudspeaker system is achieved.
IPC 1-7
IPC 8 full level
H03F 3/20 (2006.01); H04R 3/00 (2006.01); H04R 3/04 (2006.01)
CPC (source: EP)
H04R 3/002 (2013.01)
Citation (search report)
- [A] EP 0293806 A2 19881207 - YAMAHA CORP [JP]
- [A] EP 0340762 A2 19891108 - YAMAHA CORP [JP]
- [A] EP 0181608 A1 19860521 - BBE SOUND INC [US]
- [A] US 4550430 A 19851029 - MEYERS STANLEY T [US]
Designated contracting state (EPC)
DE FR GB
DOCDB simple family (publication)
EP 0435304 A2 19910703; EP 0435304 A3 19911023; EP 0435304 B1 19980729; DE 69032523 D1 19980903; DE 69032523 T2 19990408; JP 3035943 B2 20000424; JP H03196798 A 19910828
DOCDB simple family (application)
EP 90125621 A 19901227; DE 69032523 T 19901227; JP 33521089 A 19891226