Circuit for eliminating noise of audio signal

摘要

A circuit for eliminating noise from a regenerated audio signal by detecting slope of the signal. A sensor senses an edge of a head switching pulse signal to thereby generate a predetermined control pulse. The circuit has a holder for holding a state of the regenerated audio signal in response to the control pulse and permitting charge or discharge of the held signal under a given control. A slope detector detects a slope from a fixed band of the audio signal and feeds back the detected slope to thereby control charge/discharge at the holder to alter the held signal level.