Browse Prior Art Database

Original Publication Date: 2000-Nov-01
Included in the Prior Art Database: 2004-Jan-16

Publishing Venue

Sony Technical Digest

Related People

Fracka Friskey Doreian Louis Noujaim


This invention was created out of the annoying need to constantly change the volume of a car stereo in reaction to the external noise level. The invention embodies installing a microphone in the car stereo head component that monitors the external noise level in the car, and adapting the car stereo system to react to data received through the microphone. Once the user sets a desired stereo volume level, the stereo can then maintain the relative volume level throughout the listening experience. If the user enters the freeway and the noise created by the car increases, the stereo will then automatically increase its actual volume to compensate for the added noise- once the stereo adjusts its volume level, the user will still perceive a constant volume. Additions to this technology will also incorporate the ability to set maximum sound levels inside of the car. Because of a maximum sound level ceiling, users will be protected from enduring high stereo volume output in situations where the volume level is accidentally turned too high or sudden feedback is encountered. For example, a sudden increase in the stereo volume level is common when the user switches from listening to a poorly recorded tape to listening to a CD - since the sound level in the car is already being monitored and the reference signal is known, the stereo would automatically reduce the sound level to the comfortable, preset level. This invention will also be able to respond to the problem of an uncontrolled feedback loop.