CN105491478A - Subwoofer whose volume is controlled by the envelope of the TV sound - Google Patents

Abstract

A subwoofer using envelope line of television sound to control volume comprises a low-pass filter, an audio sensor, a frequency spectrum correction circuit and a voltage-controlled gain amplifier, wherein the input end of the low-pass filter is connected with the output end of a television circuit to filter out needed low-frequency audio signals; the audio sensor is arranged near a loudspeaker of the television, detects the audio signal of the television, filters the feedback of bass and other unnecessary components through the frequency spectrum correction circuit to form a level envelope representing the real-time volume of the television, then controls the volume of the low-frequency audio signal output by the low-pass filter through the voltage-controlled gain amplifier by using the level, and the low-frequency audio signal drives the loudspeaker after being amplified by the original bass amplifier of the television. The invention has the advantages that: it can match with all TV sets, compensate bass component with low cost, and improve sound quality. Simple structure and easy implementation.

Description

Subwoofer whose volume is controlled by the envelope of the TV sound

technical field

The invention relates to a subwoofer whose volume is controlled by the envelope of the TV sound, which can match all TV sets, compensate the bass component with low cost, and obviously improve the sound quality of the TV sound.

Background technique

After the color TV became thinner and lighter, the speakers became smaller and thinner, the frequency response became worse and worse, and the low frequency part was seriously insufficient. In this case, it is possible to simply add a subwoofer (commonly known as a subwoofer) to make up for the missing low-frequency part, but most of the current TVs only have a standard line output terminal for constant-level audio. The filter filters out the low-frequency part, but the output level does not adjust with the volume adjustment of the TV, that is to say, the volume of the external subwoofer cannot change in proportion to that of the TV, but each tune is different, and the user experience is very good. Weird and inconvenient. Due to this limitation, basically no product can be practically used in this way.

Contents of the invention

The purpose of the present invention is to provide a subwoofer whose volume is controlled by the envelope of the TV sound, so as to solve the problem in the prior art that after the color TV becomes thinner and thinner, the speaker becomes smaller and thinner, and the frequency response becomes worse and worse. The low frequency part is seriously insufficient.

The technical scheme of the present invention is: a kind of subwoofer controlled volume by the envelope of TV sound, it is characterized in that, comprises low-pass filter, audio frequency sensor, frequency spectrum correction circuit and voltage control gain amplifier, the input of low-pass filter The terminal is connected to the TV line output port to filter out the required low-frequency audio signal; the audio sensor is placed near the speaker of the TV, and the audio sensor detects the audio signal of the TV. After the spectrum correction circuit, the feedback of the bass and other unnecessary Components form a level envelope that represents the real-time volume of the TV, and then use this level to control the volume of the low-frequency audio signal output by the low-pass filter through the voltage-controlled gain amplifier, and the low-frequency audio signal is passed through the TV. The original bass amplifier is amplified to drive the speakers.

The invention has the advantages that it can match all TV sets, compensate the bass component with low cost (lower than soundbar+subwoofer), and greatly improve the sound quality of the sound. The structure is simple and easy to implement.

Description of drawings

Fig. 1 is a block diagram of the circuit structure of the present invention.

detailed description

Referring to Fig. 1, a kind of subwoofer of the present invention is controlled volume by the envelope curve of TV sound, is characterized in that, comprises low-pass filter 2, audio sensor 6, frequency spectrum correction circuit 7 and voltage control gain amplifier 3, low-pass filter The input terminal of the device 3 is connected with the TV line output terminal 1 to filter out the required low-frequency audio signal; the audio sensor 6 is placed near the speaker 5 of the TV, and the audio sensor 6 detects the audio signal of the TV, and after the spectrum correction circuit 7, the filter In addition to the return input of the bass and other unnecessary components, a level envelope representing the real-time volume of the TV is formed, and then this level is used to control the output of the low-pass filter 2 through a voltage-controlled gain amplifier (VCA) 3 The volume of the low-frequency audio signal, the low-frequency audio signal is amplified by the original bass amplifier 4 of the TV set to drive the speaker 5 (subwoofer).

The working principle of the present invention is: firstly filter out the required low-frequency part (low-frequency audio signal) from the full-frequency signal taken out by the TV line output terminal 1 . At the same time, the sound of the speaker of the TV is detected by the audio sensor 6 placed near the TV speaker, and the frequency spectrum is corrected by the spectrum correction circuit 7, and the feedback of the bass and other unnecessary components are filtered out, forming a representation of the real-time volume of the TV. level envelope, and then use this level to control the volume of the low-frequency audio signal through the VCA (voltage-controlled gain amplifier 3). Adjusting the volume of the TV will inevitably change the amplitude of the envelope at the same time, and the volume of the subwoofer will also change with the volume of the TV. To achieve the purpose of volume synchronization between the two. Each module circuit involved in the present invention is a conventional circuit.

The above content is a further detailed description of the present invention in conjunction with specific preferred embodiments, and it cannot be assumed that the specific implementation of the present invention is limited to these descriptions. For those of ordinary skill in the technical field to which the present invention belongs, without departing from the concept of the present invention, its architecture can be flexible and changeable, and series of products can be derived. Just making some simple deductions or replacements should be deemed to belong to the patent protection scope of the present invention determined by the submitted claims.

Claims (1)

1. one kind is controlled the subwoofer of volume by the envelope of sound of television, it is characterized in that, comprise low pass filter, audio sensor, frequency spectrum correction circuit and voltage control Amplifier, the input of low pass filter is connected with television line output, leaches the low-frequency audio signal of needs; Audio sensor is positioned near the loud speaker of television set, audio sensor detects the audio signal of TV, through frequency spectrum correction circuit, the feedback of filtering bass and other unwanted compositions, form the level envelope that represents the real-time volume of TV, the volume of the low-frequency audio signal that the low pass filter described in then being controlled by voltage control Amplifier with this level is exported, this low-frequency audio signal amplifies rear drive loud speaker through the original low playback amplifier of television set.