Methods and apparatus for alleviating sound-coupled feedback in conference room sound systems
US4378468A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 10, 1980 |
| Grant date | Mar 29, 1983 |
| Priority date | — |
| Expiry date | Oct 10, 2000 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA47B2200/0079
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A method and apparatus for alleviating sound-coupled feedback in a conference room having a conference table for the seating of human participants, the room sound system including one or more loudspeakers for outputting amplified sound from a given source in sufficient volume for all to hear plus one or more microphones for picking up the voice of any given participant. By locating the loudspeaker(s) below the board-like table top, preferably at floor level attached to the table foot structure, and by locating the microphone(s) above the table top, preferably in the central region, sound waves from the loudspeaker(s) are directed with high efficiency coupling to the participants' ears, but are constrained by the table top to "feedback" to the microphone(s) only with low efficiency coupling. "Rain barrel" effects are reduced. The invention finds advantageous use in purely local conference room sound amplification systems and in teleconferencing systems.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.