Abstract: The disclosed audio signal processing system produces an acoustic signal in a listening space and includes devices for generating a desired volume signal, a noise signal representative of ambient noise conditions in the listening space, and an audio signal. The system further includes a variable gain amplifier for amplifying the audio signal in response to a gain control signal and a device for generating the gain control signal in response to a volume control signal. The volume control signal is generated in response to the noise and desired volume signals so that the volume control signal increases in response to increases in the noise signal. The volume control signal increases at a rate of increase and the rate of increase decreases as the volume control signal increases.

Abstract: The disclosed system for estimating the ambient noise level in a listening space includes a memory for storing a plurality of noise values at memory locations therein, each of the noise values being representative of the ambient noise in the listening space associated with a corresponding set of conditions of the listening space. The system further includes an address generator for generating an address signal in response to a current set of conditions of the listening space so that the address signal accesses a location of the memory storing the noise value associated with the current set of conditions. The system further includes a noise signal generator for generating a noise signal in response to the address signal, the noise signal corresponding to the noise value associated with the current set of conditions so that the noise signal is representative of the ambient noise level.