Audio signal processing system

DETAILED DESCRIPTION What is claimed is: 1.
An audio signal processing system of the type for generating ambient effects, said system comprising: at least two channels for respectively transmitting an audio signal to at least two speakers so that one of the speakers reproduces sound in response to the audio signal at a predetermined delay with respect to the other of said speakers; means responsive to the signal level of said audio signal for producing a gain control signal as a function of the derivative of the signal level of said audio signal; and gain control means electrically connected to receive the audio signal being transmitted to said one speaker for controlling the signal gain impressed on the audio signal being transmitted to said one speaker as a function of said gain control signal; wherein said gain control means provides (A) gain reduction on (1) impulse noise transmitted in the channel for transmitting said audio signal to said one speaker and (2) audio signals of a first kind transmitted in said channel for transmitting said audio signal to said one speaker and adapted to be reproduced by said other speaker in a localized manner, and (B) signal expansion on audio signals of a second kind transmitted in said channel for transmitting said audio signal to said one speaker and adapted to be reproduced by said at least two speakers with a spatial depth.
2.
A system according to claim 1, wherein said gain control means reduces the signal gain of said impulse noise and audio signals of said first kind as a function of the magnitude of said control signal.
3.
A system according to claim 1, wherein said means for producing said gain control signal includes detection means for detecting the amplitude of said audio signal and for generating a first signal as a function of said amplitude, and means for generating a second signal as a function of derivative of the signal level of said first signal.
4.
A system according to claim 3, wherein the magnitude of said first signal is a logarithmic function of the RMS value of said audio signal