Protective system for stereo loudspeakers
US3965295A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Jul 17, 1974 |
| Grant date | Jun 22, 1976 |
| Priority date | — |
| Expiry date | Jul 17, 1994 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH03F1/305
- WIPO fieldBasic communication processes
- WIPO sectorElectrical engineering
Abstract
In an amplification system comprising an amplifier, a loudspeaker, normally open contacts connected in series between the amplifier and the speaker, and a power supply for the amplifier having relatively long buildup and decay times of its output voltage in response respectively to the connection and disconnection of the power supply to and from the a.c. line, means are provided responsive to the connection of the power supply to the a.c. line for delaying the closing of the normally open contacts until after the power supply voltage has built up to its full operating potential for eliminating the transient audio signals from the amplifier associated with power supply voltage buildup from being reproduced by the loudspeaker. Means are also provided for opening the contacts quickly after the power supply is disconnected from the a.c. line for eliminating the distorted audio signals from the amplifier associated with power supply decay from being reproduced by the loudspeaker. Additionally, if the amplifier is of the balanced type which exhibits a zero d.c. output potential during normal operation, means are provided for quickly opening the contacts upon the occurrence of a high d.c.…
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.