KR960015874B1 - Variable type surround circuit - Google Patents

Abstract

a signal transform means(10) which transforms L,R channel audio signal into multiple surround signal pattern(S1,S2,S3); a signal selection part(20) for following the specific pattern among the surround signal pattern of the signal transform means(10) under the control of a micom according to a arbitrary surround signal pattern selected by users; a time delay decision means(30) which inputs the delay time of the surround signal to the time delay part(40) by deciding the delay time of the surround signal according to the switching operation results of the signal selection part.

Description

Variable surround circuit

1 is a variable surround circuit diagram according to an embodiment of the present invention.

* Explanation of symbols for main parts of the drawings

10: signal conversion means 20: signal selection unit

30: time delay determination means 40: time delay unit

50: low pass filter 60: amplifier

The present invention relates to a variable surround circuit, and more particularly, to a variable surround circuit that obtains various surround signals by varying and outputting a surround signal in an audio device capable of surround output.

Currently, with the development of surround sound devices such as televisions and laser disc players, various devices capable of outputting sound close to the original sound have been developed, and one of the devices has a degree of listening in a theater or a concert hall. There is a surround device to get a realistic effect.

When the surround device is installed in a television, a surround device is a time delay method or a mono state in which a part of a mono sound signal transmitted from a television station is temporarily delayed and the delayed sound signal is output in two channels. Stereo device that produces stereoscopic sound effect or similar effect by using two or more channels of channel by processing voice signal by phase shifting method to shift the phase of voice signal transmitted to 2 channel and output it Say.

In addition, the surround device plays a big role in creating a boom of home theater systems in conjunction with the combination of audio and visual that started with the appearance of a home video cassette recorder (VCR). Moreover, the Dolby Surround system, a stereoscopic sound reproduction device for theaters, is becoming popular, and digital technology, which is further developed with the development of digital imaging devices such as laser disc player (LDP), is accompanied by the development of DSP (Digital Signal Processing) technology. More colorful and high-quality surround sound field, for example, according to the broadcast program received through the antenna to provide pure sound and stereoscopic surround that can maximize the realism.

In general, in the case of a television equipped with the above-mentioned surround device, a broadcast signal transmitted from a broadcasting station (that is, a mode recognition signal of a second voice signal) is detected by a broadcast mode detection circuit, and then a stereo reception mode in the case of music broadcast. In the case of movie broadcasting, the surround function is realized by reproducing the voice signal in the voice multiple reception mode.

However, although the surround device based on the time delay method or the phase shift method always outputs the audio signal by outputting two channels by the fixed time delay value or the phase shift value, it is common to the viewer or the listener. It does not provide a surround effect that fits.

Accordingly, the present invention has been made in view of the above circumstances, and an object thereof is to provide a variable surround circuit in which a surround signal can be maximized by varying a delay time of a surround signal according to a user's selection. In providing.

In order to achieve the above object, a variable surround circuit according to an embodiment of the present invention is a sound device for outputting a surround signal through a low pass filter and an amplifier after a predetermined time delay output from a time delay unit through a speaker. And a signal converting means for converting the audio signals of the L and R channels processed into audio signals into a plurality of surround signal patterns, and a surround signal from the signal converting means under the control of a microcomputer as the user selects an arbitrary surround signal pattern. And a time delay determining means for determining the delay time of the surround signal according to the switching operation result of the switching operation to follow the specific pattern among the patterns and applying the delay time of the surround signal to the time delay unit. .

According to a preferred embodiment of the present invention, the signal converting means comprises: a first signal converting unit for synthesizing and outputting the audio signals of the L and R channels, and synthesizing the audio signals of the L and R channels after a predetermined filtering operation. And a third signal converter configured to synthesize a surround signal fed back from the low pass filter together with the audio signals of the L and R channels.

According to the present invention, the first and third signal converters are composed of an OP amplifier, and the second signal converter is composed of a high pass filter, a low pass filter, and an OP amplifier.

Preferably, the time delay determining means comprises a clock oscillator to which a time constant element for holding a predetermined fixed time constant is connected, and a plurality of variable elements for varying the fixed time constant in accordance with selection by the signal selecting section. .

More preferably, the plurality of variable elements consists of a capacitor having a differential capacitance.

According to the present invention configured as described above, when the user selects a random surround signal pattern, under the control of the microcomputer, the signal selection unit selects a specific pattern and applies the surround signal of the pattern to the time delay unit. In the present invention, the surround signal is variably outputted by a variable time delay from the time delay determining means.

Hereinafter, with reference to the accompanying drawings will be described the present invention in more detail.

1 is a variable surround circuit diagram according to an embodiment of the present invention, and reference numeral 10 denotes a signal for converting audio signals of L and R channels output from audio signal processing means of a surround output capable audio device into a plurality of surround signal patterns. Conversion means.

Here, the signal converting means 10 comprises a first signal converting section 11 made up of an OP amplifier 10a for synthesizing and outputting audio signals of the L and R channels, and predetermined audio signals of the L and R channels. A second signal converter 13 composed of a high pass filter 10b, a low pass filter 10c, and an OP amplifier 10d and a low pass filter to be described later together with the L and R channel audio signals. And a third signal converter 15 composed of an OP amplifier 10e for synthesizing and outputting a surround signal fed back from 50).

In the exemplary embodiment of the present invention, a surround signal output from the first signal converter 11 is called a first surround signal S1 and a surround signal output from the second signal converter 13 is called a second signal. The surround signal S2 is referred to as a surround signal S3. The surround signal output from the third signal converter 15 is referred to as a third surround signal S3.

Reference numeral 20 denotes an arbitrary surround signal pattern (i.e., one of the first signal converter 11, the second signal converter 13, and the third signal converter 15 through a key input means not shown by the user). As a surround signal output from one signal conversion unit is selected, a specific pattern is selected from the surround signal patterns from the signal conversion means 10 based on a control signal output from a microcomputer (not shown). It is a signal selection unit as an integrated circuit (IC) switching element that switches to enable a variable surround signal output for a selection pattern.

Here, one side of the signal selector 20 is the first surround according to the control signal input terminal (A, B) receiving the control signal from the microcomputer and the input signal of the control signal input terminal (A, B) An input terminal C for selectively receiving a signal S1, an input terminal F for selectively receiving the second surround signal S2 according to an input signal of the control signal input terminals A and B, An input terminal G for selectively receiving the third surround signal S3 and the surround signals S1, S2, and S3 according to an input signal of the control signal input terminals A and B so as to be switched to be output; The off terminal D, which does not receive the surround signals S1, S2, S3, is formed according to the input signal of the output terminal E and the control signal input terminals A, B.

On the other side of the signal selector 20, variable terminals H, I, K, and L are formed to be interlocked with terminals C, D, F, and G formed on one side under the control of a microcomputer. In other words, when the input terminal C is connected, the variable terminal H is connected together, and when the off terminal D is connected, the variable terminal L is connected together, and the input terminal F is connected together. When connected, the variable terminals I are connected together. When the input terminal G is connected, the variable terminal K is connected together. On the other side of the signal selector 20, a terminal J is always maintained in a connected state.

Reference numeral 30 denotes time delay determination means for determining a delay time of the surround signal in accordance with the switching operation result of the signal selector 20.

Here, the time delay determining means 30 is connected to each other in parallel with the clock oscillator (30a) having time constant elements (R1, R2, C4) to provide a predetermined fixed time constant, and in the signal selector 20 Is composed of a plurality of variable elements (C1, C2, C3) having a differential capacitance for changing the fixed time constant of the clock oscillator (30a) according to the switching connection of the variable element (C1) (20) is connected to the variable terminal (H), the variable element (C2) is connected to the variable terminal (I), and the variable element (C3) is connected to the variable terminal (K).

On the other hand, reference numeral 40 is based on a variable clock period output from the clock oscillator 30a of the time delay determining means 30 to the arbitrary surround signal output through the output terminal (E) of the signal selector 20 A time delay unit for delaying the time, 50 is a low pass filter for removing noise components, etc. in the delayed surround signal output from the time delay unit 40, and 60 is a surround signal filtered through the low pass filter 50. Is an amplifier that amplifies a predetermined value and applies it to the speaker SP.

Referring to the surround signal output operation by the variable surround circuit according to an embodiment of the present invention configured as described above are as follows.

In FIG. 1, the audio signals of the L and R channels output from audio signal processing means installed in an audio device such as a television or laser disc player capable of surround output are first to third signals constituting the signal conversion means 10. As shown in FIG. The control unit 11, 13, and 15 are applied to the control signal input terminals A and B of the signal selection unit 20. The control signal from the microcomputer (i.e., control by selecting a surround signal pattern desired by the user) Signal is applied.

First, when a user inputs a predetermined selection signal using a key input means (not shown) to perform sound listening by the surround signal S1 pattern output from the first signal conversion unit 11, a microcomputer (not shown) ) Applies a control signal (eg, '11') corresponding to the selection signal to the control signal input terminals A and B of the signal selection unit 20. Subsequently, the signal selector 20 connects the input terminal C for signal input and the variable terminals H, I, and K connected to the variable elements C1, C2, and C3 to provide a variable value. The variable terminal H is connected. Accordingly, the surround signal S1 (that is, a surround signal obtained by synthesizing and outputting audio signals of L and R channels in the OP amplifier 10a) is transmitted through the input terminal C and the output terminal E. FIG. The time delay unit 40 is applied to the time delay unit 40, and the time delay unit 40 is supplied from the clock oscillator 30a in the time delay determination unit 30 whose time constant is determined by the resistors R1 and R2 and the capacitor C1. The time delay operation of the surround signal S1 is performed according to a clock signal. Thereafter, the time delayed surround signal S1 output from the time delay unit 40 is removed from the low frequency filter 50, the noise component is amplified by the amplifier 60, and then output through the speaker SP. .

On the other hand, when the user inputs a predetermined selection signal for sound listening by the surround signal S2 pattern output from the second signal conversion unit 13, the microcomputer receives a control signal corresponding to the selection signal (eg, ' 10 ') is applied to the control signal input terminals A and B of the signal selector 20. Subsequently, the signal selector 20 connects the input terminal F for signal input and the multi-sided terminals H, I, and K connected to the variable elements C1, C2, and C3 to provide a variable value. The variable terminal I is connected. Accordingly, the surround signal S2 (that is, a surround signal obtained by synthesizing and outputting the audio signals of the L and R channels respectively filtered by the high pass filter 10b and the low pass filter 10c by the OP amplifier 10d). Is applied to the time delay unit 40 through the input terminal (F) and the output terminal (E), the time delay unit 40 is a time constant is determined by the resistor (R1, R2) and capacitor (C2) The time delay operation of the surround signal S2 is performed in accordance with the clock signal from the clock oscillator 30a in the time delay determining means 30. Thereafter, the time delayed surround signal S2 output from the time delay unit 40 is removed from the low frequency filter 50, the noise component is amplified by the amplifier 60, and then output through the speaker SP. .

In addition, when a user inputs a predetermined selection signal for sound listening by the surround signal S3 pattern output from the third signal converter 15, the microcomputer receives a control signal corresponding to the selection signal (eg, ' 01 ') is applied to the control signal input terminals A and B of the signal selector 20. Subsequently, the signal selector 20 connects the input terminal G for signal input and the variable terminals H, I, and K connected to the variable elements C1, C2, and C3 to provide a variable value. ) Is connected to the variable terminal (K). Accordingly, the surround signal S2 (that is, the surround signal according to the synthesis of the audio signal of the L and R channels performed by the OP amplifier 10e and the surround signal fed back from the low pass filter 50) is The time delay unit 40 is applied to the time delay unit 40 through the input terminal G and the output terminal E, and the time delay unit 40 is a time constant determined by the resistors R1 and R2 and the capacitor C3. The time delay operation of the surround signal S3 is performed in accordance with the clock signal from the clock oscillator 30a in the delay determining means 30. Thereafter, the time delayed surround signal S3 output from the time delay unit 40 is removed from the low frequency filter 50, the noise component is amplified by the amplifier 60, and then output through the speaker SP. .

In addition, when the user operates a predetermined variable surround off button (not shown) installed in the key input means, the microcomputer outputs a control signal (eg, '00') corresponding to the off signal to the signal selector 20. Is applied to the control signal input terminals (A, B). Subsequently, the signal selector 20 may not receive the surround signals S1, S2, and S3 output from the first to third signal converters 11, 13, and 15 under the control of the microcomputer. D) and variable terminal L are connected. Accordingly, since there is no signal applied to the time delay unit 40 through the signal selection unit 20 and the time delay determination unit 30, the sound device is switched to the previous output state.

As described above, according to the present invention, when the user selects a random surround signal pattern, the currently output surround signal is variably output. Thus, the surround effect may be increased as compared with the conventional method of outputting a surround sound having a predetermined pattern. There is an advantage to this.

Claims (5)

In a sound device that outputs a surround signal through the low pass filter 50 and the amplifier 60 after a predetermined time delay output from the time delay unit 40 via the speaker SP, L and R processed with audio signals. Signal converting means 10 for converting the audio signal of the channel into a plurality of surround signal patterns (S1, S2, S3) and the signal converting means (10) under the control of the microcomputer as the user selects an arbitrary surround signal pattern. In order to estimate a specific pattern among the surround signal patterns from), the delay time of the corresponding surround signal is determined according to the switching operation result of the switching operation of the signal selection unit 20 and the signal selection unit 20. 40. A variable surround circuit, characterized in that it further comprises a time delay determining means (30) to be applied to. 2. The signal converting means (10) according to claim 1, wherein the signal converting means (10) comprises a first signal converting section (11) for synthesizing and outputting audio signals of the L and R channels, and a predetermined filtering operation on the audio signals of the L and R channels. And a third signal converter 15 for synthesizing and outputting a surround signal fed back from the low pass filter 50 together with the audio signals of the L and R channels. Variable surround circuit characterized by. 3. The first and third signal converters 11 and 15 are composed of OP amplifiers 10a and 10e, and the second signal converter 13 comprises a high pass filter 10b and a low pass filter. 10c) and an OP amplifier 10d. The signal delay unit (30) according to claim 1, wherein said time delay determining means (30) comprises a clock oscillator (30a) to which time constant elements (R, R2, and C4) for holding a predetermined fixed time constant are connected; A variable surround circuit comprising a plurality of variable elements (C1, C2, C3) for varying the fixed time constant according to the selection. 5. The variable surround circuit according to claim 4, wherein the plurality of variable elements (C1, C2, C3) are composed of capacitors having differential capacitance.