Electrical audio signal processing systems and devices – Directive circuits for microphones
Patent
1993-03-23
1994-04-12
Isen, Forester W.
Electrical audio signal processing systems and devices
Directive circuits for microphones
H04R 300
Patent
active
053033078
ABSTRACT:
A method and apparatus for providing a differential microphone with a desired frequency response are disclosed. The desired frequency response is provided by operation of a filter, having an adjustable frequency response, coupled to the microphone. The frequency response of the filter is set by operation of a controller, also coupled to the microphone, based on signals received from the microphone. The desired frequency response may be determined based upon the distance between the microphone and a source of sound, and may comprise both a relative frequency response and absolute output level. The frequency response of the filter may comprise the substantial inverse of the frequency response of the microphone to provide a flat response. Furthermore, the filter may comprise a Butterworth filter.
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Elko Gary W.
Kubli Robert A.
Morgan Dennis R.
West James E.
AT&T Bell Laboratories
Isen Forester W.
Restaino Thomas A.
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