Noise reduction circuit

Details Noise reduction circuit Noise reduction circuit

1981-08-31

1984-01-24

Mullins, James B.

Amplifiers

Hum or noise or distortion bucking introduced into signal...

330284, H03F 126, H03G 310

Patent

active

044279507

ABSTRACT:
A noise reduction circuit for use in an audio signal recording/reproducing apparatus includes a first filter circuit for providing frequency emphasis to a signal supplied thereto; a first signal path connected in series with the first filter circuit, and including a voltage-controlled amplifier for amplifying a signal supplied thereto with controllable gain and a second filter circuit for providing frequency emphasis to the signal passing through the voltage-controlled amplifier; a level detecting circuit for controlling the gain of the voltage-controlled amplifier in response to the level of the signal passing through the voltage-controlled amplifier; a resistor connected to the first signal path for reducing the effect of the frequency emphasis by the second filter circuit when the level of the signal passing through the voltage-controlled amplifier is reduced; and a low pass filter circuit connected with the first signal path for reducing the effect of the frequency emphasis by the first and second filter circuits when the level of the signal passing through the voltage-controlled amplifier is high; wherein the circuit for noise reduction provides a first amount of frequency emphasis for intermediate level signals supplied thereto and a second lower amount of frequency emphasis for low and high level signals supplied thereto. When used in its encoding mode, the first and second filter circuits each include a high-pass filter circuit, and when used in its decoding mode, these filter circuits each include a low-pass filter circuit.

REFERENCES:
patent: 4281295 (1981-07-01), Nishimura

Affiliated with

Also associated with

Rating

Noise reduction circuit does not yet have a rating. At this time, there are no reviews or comments for this patent.

If you have personal experience with Noise reduction circuit, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Noise reduction circuit will most certainly appreciate the feedback.

Rate now

Comments { 0 }

Profile ID: LFUS-PAI-O-1289698