Adjustable filter for differential microphones
US5303307A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 23, 1993 |
| Grant date | Apr 12, 1994 |
| Priority date | — |
| Expiry date | Mar 23, 2013 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R3/08
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
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.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.