Broadband acoustical transmitting system
US5821470A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Apr 8, 1997 |
| Grant date | Oct 13, 1998 |
| Priority date | — |
| Expiry date | Apr 8, 2017 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH04R1/30
- WIPO fieldAudio-visual technology
- WIPO sectorElectrical engineering
Abstract
An acoustical transmitting system and method for producing a narrow beam of acoustic energy over a broadband operating frequency range utilizes a parabolic reflector dish, a horn-loaded compression driver for directing acoustic energy toward the dish's reflecting surface, and a low frequency driver mounted behind a central aperture in the dish for producing acoustic energy that combines and interacts with the reflected acoustic energy produced by the horn-loaded compression driver. An input signal processing circuit is provided to condition the audio signal to the horn-loaded compression driver and the low frequency driver to achieve on-axis gain and off-axis cancellations at low frequencies. The addition of the low frequency driver to the reflector dish system effectively extends the ability of the system to produce and transmit acoustic energy in a narrow distribution pattern at frequencies below 1000 Hz using a four foot diameter dish.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.