The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 01, 1991
Filed:
Apr. 12, 1988
Masami Kato, Ora, JP;
Katsu Horikoshi, Tatebayashi, JP;
Sanyo Electric Co., Ltd., Osaka, JP;
Abstract
An automatic loudness control circuit for automatically controlling the magnitude of boosting of the low-frequency component of an audio signal in accordance with the output signal level of a power amplifier for driving a loud-speaker. The low-frequency component of the output signal from an audio signal source is boosted by a low frequency boosting circuit to prepare a low-frequency boost signal, which is then added to the output signal of the source, and the resulting signal is fed to the power amplifier. The magnitude of boosting by the boosting circuit is controlled according to the output level of the power amplifier and is therefore increased as the output level lowers. Consequently, the circuit assures optimum loudness control at all times, permitting the loudspeaker to produce dynamic sounds.