04061874 is referenced by 39 patents and cites 5 patents.

In an environment of acoustic noise, such as a car radio playing in traffic or engine noise, both the volume (AGC) and dynamic range (Compression) of the audio amplifier are controlled by a local ambient acoustic noise sensor, such that gain is increased and dynamic range decreased simultaneously with increased ambient noise.

Title
System for reproducing sound information
Application Number
5/692441
Publication Number
4061874
Application Date
June 3, 1976
Publication Date
December 6, 1977
Inventor
Ulrich R Muller
Siegstrasse 2, Lovenich
DT
J P Fricke
Wullnerstrasse 100, Cologne
DT
Agent
Flynn & Frishauf
IPC
H03G 9/18
H03G 3/20
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