SU1012460A1 - Device for suppressing low-frequency noise in stereophonic electric record player - Google Patents

Abstract

A DEVICE TO SUPPRESS A LOW-FREQUENCY ROUND BY A VTEREO-PHONICAL ELECTRO-PLAYER, containing an adder-inverter and two channels, each of which contains a low-pass filter and an output adder, characterized in that. In order to increase the suppression efficiency by eliminating the influence of the low frequency filter parameters on the amplitude-frequency characteristics of the channels, an additional adder is added to each channel, the input of each cable is connected to an inverter with an input of the adder, and with the corresponding input the input of the adder-inverter, the output of the adder-inverter is connected to the second inputs of the input adders of both channels, the output of the input adder of each channel through the filter is low frequency is connected to the inverting input of the output adder. (/)

Description

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The invention relates to electroacoustics and can be used to deliver low-frequency roar in high-quality electric replay players.

A device for suppressing a low-frequency rumble in a stereo electric player is known, consisting of two voltage dividers and compensation circuits that sum the signals of the stereo device in the low-frequency region f 1.

The disadvantage of such a device is the small amount of transient attenuation of the correction circuits in the medium frequency range.

It is also known to suppress a low-frequency rumble in a stereo electric player, consisting of an inverter combiner — and two channels, each of which contains a low-pass filter connected in series, an inverter, and an output adder t2.

A disadvantage of the known device is the effect of the variation of the parameters of low-pass filters on the amplitude-frequency characteristic of the channels.

The aim of the invention is to increase the suppression efficiency by eliminating the influence of the spread of low pass filter parameters on the amplitude-frequency characteristics of the channels.

The goal is achieved by the fact that in the device of suppressing a low-frequency rumble in a stereo electric player containing an adder-inverter and two channels, each of which contains a low-pass filter and an output adder, an additional adder is added to each channel, and the input of each channel is connected to an inverting the input of the output adder, with the first input of the input adder and with the corresponding input of the adder .-. inverter, the output of the adder-inverter is connected to the second inputs of the input adders their channels, the output of the adder of each channel

through a low-frequency filter is connected to the non-inverting input of the output adder.

In the drawing, a schematic representation of the proposed device.

The device contains cy1 1mator-inverter 1, input adders of channels 2 and 3, low-frequency filters 4 and 5, output adders 6 and 7.

The operation of the device is as follows.

The signals of the left and right channels of the stereo electric player are fed to the corresponding inputs of the device. In each channel, the signals arrive at the inverting inputs of the output adders b and 7 and to the first inputs of the input adders 2, 3 with a single transmission coefficient, as well as to the two inputs of the adder-inverter 1 with a transmission coefficient 1/2. In the adder-inverter 1, a mono channel is formed and, from its output, the signal goes to the second inputs of adders 2, 3. Then, in each channel after the low-frequency filter 4 (5), the low-frequency part of the signals goes to the non-inverting input of adder b (7).

In adder 2 (3), the full-spectrum signal of its channel with the full mono signal is summed. Filter 4 (5) separates the low frequency portions of these two signals. In the output adder b (7), the low frequency part of the same channel is subtracted from the full signal of its channel (with a roar). la (with rumble) and instead of it a low-frequency part (without rumble) is added, separated by the same filter 4 (h) from the full mono signal.

Due to the fact that the replaceable and replacing low-frequency parts of the signal are separated in the filter with one filter, the amplitude-frequency characteristic of the channel does not undergo distortion.

The use of this device allows one to exclude the influence of the spread of low pass filter parameters on the amplitude-frequency characteristic of the device.

Claims (1)

DEVICE FOR SUPPRESSING LOW FREQUENCY MOUTH IN A STEREOPHONIC ELECTRIC PLAYER, containing an adder-inverter and two channels; each of which contains a low-pass filter and an output adder, characterized in that, in order to increase the suppression efficiency by eliminating the influence of the spread of low-pass filter parameters on the amplitude-frequency characteristics of the channels, an additional input adder is introduced into each channel, with the input of each channel connected to the inverting input of the output adder, to the first input of the input adder and to the corresponding input of the adder-inverter, the output of the adder-inverter is connected to the second inputs of the input adder mators of both channels, the output of the input adder of each channel through a low-pass filter is connected to the inverting input of the output adder.