Sound encoding system

摘要

A signal encoding system for generating at least two encoded signals in response to a plurality of information signals containing audio data representative of virtual images of sources of the data so that the encoded signals can be subsequently decoded by a decoding system including a decoding matrix means for decoding the encoded signals so as to regenerate the information signals. The signal encoding system comprises signal encoding means for generating the encoded signals in response to the information signals; and a duplicate of the decoding matrix means coupled to the encoding means for generating a feedback signal corresponding to each of the information signals; wherein the encoding signals are modified in response to the feedback signals so as to reduce the noise artifacts generated by the decoding matrix when the encoded signals are decoded by the decoding system. A system is also disclosed for modifying the signal gain impressed on an input signal so as to modify the dynamic range of at least a portion of the input signal wherein the system is of the type including operational amplification means for generating an output signal in response to the input signal and feedback means disposed in a feedback path of the operational amplification means for generating a feedback signal for the operational amplification means, wherein the feedback means includes means responsive to the output signal for impressing a gain on the feedback signal in response to and as a function of a control signal, and means for generating the control signal in response to and as a function of the output signal. The improvement comprises: the operational amplification means including means responsive to the input signal and the feedback signal for modifying the signal gain impressed on the input and feedback signals in response to a second control signal; and means for generating the second control signal in response to at least a portion of the feedback signal.