Acoustic sound system for a room
US4837829A · kind A · utility
Assignee
Inventor
Key dates
| Filing date | Oct 8, 1987 |
| Grant date | Jun 6, 1989 |
| Priority date | — |
| Expiry date | Oct 8, 2007 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R27/00
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
A modular acoustic sound system for a room for two-way conversations without the need for switching. The system includes pairs of microphones each connected to a phase shifter so that in-phase signals inputted to the microphone pair are shifted 180.degree. apart. The out-of-phase signals are input to a summing circuit having an amplified output which drives a plurality of loudspeakers. A portion of the audible loudspeaker outputs enters the microphone pair, is phase shifted, and cancelled out in the summing amplifier. Any number of loudspeaker/microphone pairs operate in the system and any microphone may be spoken into to drive every loudspeaker.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.