Title:
ACOUSTIC DEVICE
Document Type and Number:
WIPO Patent Application WO/2021/187139
Kind Code:
A1
Abstract:
The present invention improves the efficiency η of an acoustic device as a whole including an amplifier, over an entire frequency band including a lowest resonance frequency F0. An acoustic device 10 comprises a class-D amplifier 1 and a speaker system SS including a voice coil driven by the class-D amplifier 1. The class-D amplifier 1 is provided with a current feedback circuit 200. The speaker system SS has a Q-value lower than a lower limit value of an appropriate range. The current feedback circuit 200 increases the output resistance of the class-D amplifier by feeding a current flowing through the voice coil back to an input unit of the class-D amplifier 1, and thereby increases the Q-value of the acoustic device 10 to a value within the appropriate range.
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Inventors:
OHTANI YOHEI (JP)
NORO MASAO (JP)
NORO MASAO (JP)
Application Number:
PCT/JP2021/008461
Publication Date:
September 23, 2021
Filing Date:
March 04, 2021
Export Citation:
Assignee:
YAMAHA CORP (JP)
International Classes:
H04R3/04; H03F1/34; H03F3/217
Foreign References:
| JP2016025475A | 2016-02-08 |
Attorney, Agent or Firm:
CHUBU PATENT OFFICE (JP)
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