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:
Sep. 21, 2004
Filed:
Dec. 06, 2000
Aki Mäkivirta, Lapinlahti, FI;
Ari Varla, Iisalmi, FI;
Genelec Oy, Iisalmi, FI;
Abstract
A method and apparatus for attenuating acoustic reflections related to sound radiated by a loudspeaker in an acoustic space. According to the method, at least one cancelling loudspeaker is used for radiating a canceling sound in the space. The signal required for producing the cancelling sound is sampled from the sound reproduction apparatus prior to the processing of the original sound signal for emission into the acoustic space. The sample signal is low-pass filtered, delayed, amplified and inverted prior to being taken to the cancelling loudspeaker. The sound reproduction apparatus includes a signal sampling device, control devices, and at least one cancelling loudspeaker for radiating the cancelling sound.