SU1061247A1 - Volume level control unit - Google Patents

Abstract

THE DEVICE OF ADJUSTMENT OF THE LEVEL OF SOUND, containing serially connected input and output adjustable amplifiers, as well as two control circuits connected to the output of the input adjustable amplifier, the first of which contains serially connected input frequency-dependent element, the first detector and the first loop filter, the second serially connected input A detector and a second loop filter, characterized in that, in order to reduce the difference in the loudness of the sound of the Speech-Music signals, between Odom second loop filter and the control input of the output kschdam controlled amplifier enabled key and output of the first loop filter connected to the control inputs of the controlled input Wuxi .litel and key. (L

Description

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The invention relates to electroacoustics and can be used in the transmission of acoustic signals to a wide range of listeners, for example, in magnetic and recording, broadcasting, and sound of television.

A device for converting acoustic signals is known, comprising an adjustable amplifier and a control channel, which in turn, contains a weighting filter, a set of band-pass filters, rectifiers, a timing circuit. In the control channel, the level of the spectral components of the acoustic signal is estimated and the control signal is generated, which changes the gain of the adjustable amplifier in a certain correspondence with the change in the volume of the transmitted acoustic signals C1.

The disadvantage of such a transformation is. The body concludes with a low leveling efficiency when alternating acoustic signals of speech and music, i.e. These signals have different spectral and temporal characteristics, and in the device they are converted equally.

Closest to the invention is a sound level control device comprising successively connected input and output adjustable amplifiers, as well as two control circuits connected to the output of the input adjustable amplifier, the first of which contains a series-connected input frequency-dependent element, the first detector and the first loop filter, a second serially connected input detector and a second loop filter C2 J.

The disadvantage of this device is the low level of equalization of successive speech and musical signals, since it only provides a decrease in the volume of excessively loud acoustic signals and does not allow an increase in the volume of quietly heard fragments of speech or music. If you artificially increase the volume of speech signals by increasing THEIR level, this can be a noticeable distortion in the dynamics of musical signals, especially symphonic music.

The purpose of the invention is to reduce the difference in loudness levels of sound signals Speech - Music.

The goal is achieved by the fact that in the adjustment device

a sound level containing serially connected input and output adjustable amplifiers, as well as two control circuits connected to the output of an input adjustable amplifier, the first of which contains a series-connected input frequency-dependent element, the first detector and the first loop filter, the second is therefore connected by input detector and second loop filter, between the output of the second loop filter and the control input of the output adjustable amplifier

5, the key is turned on, and the output of the first loop filter is connected to the control inputs of the adjustable input amplifier and the key.

The drawing shows the structural scheme of the proposed sound adjustment device.

The device contains an input adjustable amplifier1, output

5, adjustable amplifier 2, first control circuit 3, second control circuit 4, input frequency-dependent element 5, first detector b, first loop filter 7, input detector 8, second loop filter 9 and key 10.

The device works as follows.

The input signal passes through

5 input adjustable amplifier 1 and is fed to the inputs of the first and second circuits 3 and 4 of the control. Since the first control circuit 3 contains an input frequency-dependent element 5, as the amplitude of the high-frequency components increases in the input signal spectrum, which is typical of music, the transmission ratio of the adjustable amplifier 1 decreases. This leads to a decrease in

5 levels of the transmitted signal and, consequently, to a decrease in its volume.

The parameters of the first loop filter 7 are selected so that

0 adjustment of the average level of transmitted signals was carried out unnoticed by ear (this corresponds to a response time of about 0.3-0.6 s, and a recovery time of 10-12 s).

5 At excessively low levels of signals at the output of the input adjustable amplifier 1, the output adjustable amplifier 2 amplifies the output signals by 6-8 dB. Wherein

for music signals with a high level of high-frequency components, amplification does not occur, since the key 10, controlled from the output of the first control circuit 3, disconnects the output of the second control circuit 4 from

control of the input of the output adjustable amplifier 2. On the voice signals of the second control circuit 4 is turned off, and the amplification does not occur when the level at the input of the output adjustable amplifier 2 is close to the nominal one. Thus, for quiet speech signals, additional amplification of loudness occurs, speech signals and symphonic music are not subject to additional amplification, and the level of pop music signals, which have high energy throughout the whole spectrum, is reduced when the input adjustable amplifier 1 is used.

Thus, the proposed device for adjusting the sound level allows leveling the volume of the speech and music.

Claims (1)

SOUND LEVEL CONTROL DEVICE, comprising adjustable-connected input and output adjustable amplifiers in series, as well as two control circuits connected to the output of the adjustable adjustable amplifier, the first of which contains a frequency-dependent input element in series, the first detector and the first loop filter, the second a series-connected input detector and a second loop filter, characterized in that, in order to reduce the difference in volume levels of the sound of Speech-Musies signals, between the output m of the second loop filter and the control input of the output adjustable amplifier includes a key, and the output of the first loop filter is connected to the control inputs of the input adjustable amplifier and key. su _m , 1061247