Noise suppressor

A noise suppressor comprising:

• a first detector for detecting a noise or a vibration of a noise source;
• a first digital filter for processing a noise signal detected by said first detector;
• an adder for adding an output signal from said first digital filter and an audio signal from audio equipment;
• a speaker for reproducing an output signal from said adder;
• a second detector for detecting a sound signal at a listening point;
• a second digital filter for processing an audio signal outputted from said audio equipment;
• a computing circuit for computing a signal detected by said second detector and an output signal from said second digital filter;
• a first switching circuit for effecting switching of an output signal from said first detector and an audio signal from said audio equipment;
• a coefficient control circuit for controlling a coefficient of said first digital filter and that of second digital filter in response to an output signal from said first switch circuit and that from said computing circuit;
• and
• a second switching circuit for switching an output signal from said coefficient control circuit to said first and second digital filters.