JPH0847100A - Sound field localization operation unit - Google Patents

Abstract

PURPOSE:To provide an inexpensive sound field localization operation unit by which a position of a sound image is revised freely by 360 deg. only with two left and (left and right speakers) right speakers. CONSTITUTION:This operation unit is provided with input amplifiers 1L, 1R provided to two left right input channels, signal balance circuits 2L, 2R dividing the original sound signal outputted from the amplifiers 1L, 1R into 1st and 2nd original sound signals and setting the balance respectively, common mode signal elimination circuits 3L, 3R eliminating a common mode component from the 2nd original sound signal of each channel and forming only different phase components, buffer amplifiers 4L, 4R inverting respectively the 1st original sound signal, mixing amplifiers 5L, 5R synthesizing an output signal of the buffer amplifiers 4L, 4R with an output signal from the common mode signal elimination circuit, and a 3rd variable resistor (Pan) 6 varying the balance of the left and right signals outputted from the mixing amplifiers 5L, 5R, and the 1st and 2nd variable resistors and a 3rd variable resistor 6 of the signal balance circuits 2L, 2R are controlled to set the sound image position to a prescribed position in the horizontal and vertical directions.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound field localization control device, and more specifically, a surround type sound field is formed by two left and right speakers, and the position of a sound image can be freely changed in the front, rear, left and right directions. The present invention relates to a sound field localization operating device capable of performing the above.

[0002]

2. Description of the Related Art As a device for controlling a surround type sound field, for example, a sound field localization operating device disclosed in Japanese Utility Model Publication No. 2-10700 is known. This device uses a control signal from the joystick of a game console to send a CRT
In addition to the operation of moving the game character displayed on the display, the functions of controlling the gains of the four gain control amplifiers to configure the multi-source sound field and simultaneously controlling the localization of the sound image are combined, and each is controlled from the output matrix circuit. Audio signals are output from four speakers via an amplifier, and the localization movement of video and audio is interlocked regardless of the game program.

[0003]

However, in this prior art example, it is premised that four speakers are used, and the joystick is operated for four channels, and the speaker, amplifier, etc. are for four channels each. It must be prepared, and of course, the cost is inevitably high.

Further, although surround processors and effectors are known, in the conventional surround processors and matrix surrounds, the user can only select a surround pattern.

On the other hand, in the case of a circuit in which the position of the sound image can be freely changed, its operation can be varied only stepwise by a tact switch or the like, which allows the user to adjust to the tune or rhythm. The sound image cannot be changed quickly. Of course, a digital surround system device can change the sound image speedily, but it has a large number of circuit parts and requires the use of a digital signal processor, which makes the price very high.

The present invention has been made in view of such a background, and an object thereof is an inexpensive sound field localization operation device capable of freely changing the position of a sound image by 360 ° by only two speakers on the left and right. To provide.

[0007]

In order to achieve the above object, the present invention provides an input signal amplifying means provided in each of two left and right input channels and an original sound signal output from each input signal amplifying means. A pair of signal balance means, which is divided into a first original sound signal and a second original sound signal, and which sets a balance amount of both original sound signals, and a pair of signal balance means, and the signal balance means outputs the signals. Buffer means for making the respective first original sound signals having opposite phases different from each other, and in-phase signal removing means for removing the in-phase components from the respective second original sound signals outputted from the respective signal balancing means and making only the different-phase components. A signal synthesizing means for synthesizing the output signal of each of the buffer means and the output signal of the in-phase signal removing means for each channel, and the output from the both signal synthesizing means A third volume for varying the balance of the left and right signals, an output signal amplification means for amplifying and outputting the left and right signals whose balance is changed by the third volume, and output signals of these output signal amplification means. Is provided as two pieces of left and right speakers for outputting as sound information, and sound image position operation means for operating the first to third volumes to set the sound image position to a predetermined position in front, rear, left and right.

In this case, it is preferable that the sound image position operating means is constituted by a stick volume for operating the first, second and third volumes by one stick.

[0009]

According to the above construction, the audio signal (original sound signal) amplified by the input signal amplifying means for each channel is adjusted by the first and second volumes of the signal balance means at the next stage to obtain the first sound signal for each channel. It is divided into one original sound signal and the first original sound signal, and the balance amount thereof is taken. Each of the first original sound signals is input to the buffer means for each channel and the phase thereof is inverted to be the opposite phase.

On the other hand, each second original sound signal is input to the in-phase signal removing means, and after the in-phase component of both channels is removed by the in-phase signal removing means, for example, a differential amplifier, only the out-of-phase component is removed.
In the signal synthesizing means, the buffer means synthesizes the first original sound signal having the opposite phase. Then, the output balance of each signal synthesizing means is varied by the third volume (Pan), and the signals are output from the left and right speakers via the output amplifier.

In this case, it is necessary to make the signal level output from the common-mode signal removal means higher than the signal level output from the buffer means. The proper level of this signal level balance differs depending on the equipment using this circuit, but by properly setting the level, it is possible to effectively move the sound image. Also, the surround feeling is increased. By using the stick volume, the position of the sound image can be easily moved from the front to the right, the rear, and the left by operating the position of one stick.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. As shown in FIG. 1, this sound field localization operating device includes an input amplifier 1L as an input signal amplifying means,
1R and a signal balance circuit 2 as signal balance means
L and 2R, in-phase signal removing circuits 3L and 3R as in-phase signal removing means, buffer amplifiers 4L and 4R as buffering means, and a mix amplifier 5 as signal synthesizing means.
L, 5R, Pan 6, and output amplifiers 7L, 7R are provided. Hereinafter, L represents the left channel and R represents the right channel.

The input amplifiers 1L and 1R are amplifiers for amplifying audio signals input from left and right from an audio reproducing device such as a compact disk or tape (not shown) for each channel and outputting the amplified signals to the signal balance circuits 2L and 2R. This may be known.

In this embodiment, the signal balance circuit 2
L and 2R are the first and second volumes 8 and 8, respectively.
The input signal (original sound signal) input from the input amplifiers 1L and 1R is divided into a first original sound signal and a second original sound signal by the respective volumes 8 and 9, and
The balance amounts of the both are adjusted, one first original sound signal is output to the buffer amplifiers 4L and 4R, and the other second original sound signal is output to the in-phase signal removal circuits 3L and 3R, respectively.

The in-phase signal removing circuits 3L and 3R are composed of differential amplifiers. In this case, the second original sound signal on the right channel R side is input to the inverting terminal of one in-phase signal removing circuit 3L, The second original sound signal on the left channel L side is input to the non-inverting terminal, the in-phase component of both the second original sound signals is removed, and only the out-of-phase component is left.

The second original sound signal on the left channel L side is input to the inverting terminal of the other in-phase signal removing circuit 3R,
The second original sound signal on the right channel R side is input to the non-inverting terminal, the in-phase component of both second original sound signals is removed, and only the out-of-phase component is left.

On the other hand, the signal balance circuits 2L and 2L
The first original sound signal output from R is supplied to each buffer amplifier 4
The phases of L and 4R are reversed. The first original sound signals having the opposite phase are mixed with the out-of-phase component signals output from the in-phase signal removing circuits 3L and 3R and the mix amplifiers 5L and 5L.
The signal is input to 5R, and the first original sound signal and the out-of-phase component are combined.

The outputs of the mix amplifiers 5L and 5R are
The left and right balance amounts are made variable by the Pan 6 including the third volume 10, and the speaker is driven by the power amplifier (not shown) via the output amplifiers 7L and 7R.

In this embodiment, the first, second and third volumes 8, 9, 10 are one stick 12 provided on the stick volume body 11 as shown in the plan view of FIG. It is designed to be operated in conjunction with each other.

Next, the operation of this sound field localization operating device will be described. Input signals of left and right channels (original signal) _V, respectively L _{(t), V} and R (t), each amplifier, i.e. input amplifier 1L, 1R, common mode rejection circuit (differential amplifier) 3L, 3R, buffer The amplification factors of the amplifiers 4L and 4R, the mix amplifiers 5L and 5R, and the output amplifiers 7L and 7R are A ₁ , A ₂ , A ₃ , A ₄ , and A ₅ , respectively, and the resistance value of each fixed resistance of the signal balance circuits 2L and 2R. Is R, the total resistance value of the variable resistor is R _A , and the resistance component when the sliding contact of each of the volumes 8 and 9 is moved is y, when moving the sound image back and forth, Become.

That is, V _L (t) and V _R (t) input to the respective channels L and R are amplified by the input amplifiers 1L and 1R, and are amplified by the first signals in the signal balance circuits 2L and 2R.
The original sound signals V _L1 (t) and V _R1 (t) and the second original sound signals V ′ _L1 (t) and V ′ _R1 (t), among which the first original sound signal V _L1 (t), V _R1 (t) is amplified by the buffer amplifiers 4L and 4R and becomes signals V _L2 (t) and V _R2 (t) as shown in Formula 1 and Formula 2.

[0022]

[Equation 1]

[0023]

[Equation 2] In addition, the second original sound signals V ′ _L1 (t) and V ′ _R1 (t)
Are expressed by the following mathematical expressions 3 and 4, and the respective second original sound signals are input to the in-phase signal removing circuits 3L and 3R.

[0024]

(Equation 3)

[0025]

[Equation 4] Then, the in-phase signal removing circuits 3L and 3R remove the in-phase components from the second original sound signal of each channel, and the out-of-phase component signal V'as shown in the following equations 5 and 6 is obtained.
_L2 (t) and _V'R2 (t) are output.

[0026]

(Equation 5)

[0027]

(Equation 6) Here, when the position of the stick 12 of the stick volume 11 is rearward, if the amplification factors of the in-phase signal removal circuits 3L and 3R are set to A ₃ > 1, in order to further exert the sound image effect, the mix amplifiers 5L and 5R are set. Output V
_L3 (t) and V _R3 (t) are expressed by the following _formulas 7 and 8
become that way. The amplification factors A ₁ and A ₂ of the input amplifiers 1L and 1R and the buffer amplifiers 4L and 4R are 1 respectively.
Is.

[0028]

(Equation 7)

[0029]

(Equation 8) Here, the position of the stick 12 for operating the first and second volumes 8 and 9 is the front position, that is, x =
R _A, in the case of y = 0, the gain is set to be 1, keep as shown mix amplifiers 4L, the amplification factor _{A 4} of 4R number 9. Note that x is a resistance value that changes when the stick 12 is moved in the X-axis direction.

[0030]

[Equation 9] When the output signals are combined in this way, the resistance value of the first and second volumes 8 and 9 is 0 (Ω) ≦ y ≦ _RA (Ω) by moving the position of the stick 12 back and forth.
, And the signal V shown in Equation 1 and Equation 2
The mixing ratio of _L2 (t) and V _R2 (t) to the out-of-phase component signals V ′ _L2 (t) and V ′ _R2 (t) shown in Equations 5 and 6 changes, and the sound image is y = _RA When it is, it feels like it is on the front side, and when y = 0, it feels like it is on the rear side.

The sound image thus moved back and forth is
The third volume 10 of the Pan 6 moves in the left-right direction. That is, the combined signals of the left and right channels L and R output from the mix amplifiers 5L and 5R are divided by the third volume 10 of the Pan 6, and the signals V _L4 (t) and V _R4 ( t).

[0032]

[Equation 10]

[0033]

[Equation 11] The signals V _L4 (t) and V _R4 (t) are output to the output amplifier 7
The signals V _LO (t) and V _R4 (t) shown in _Expressions 12 and 13 are amplified by L and 7R.

[0034]

(Equation 12)

[0035]

(Equation 13) Here, the amplification factor A ₅ of the output amplifiers 7L and 7R is set as shown in the following formula 14 so that the gain becomes 1 when the stick 12 is located at the center.

[0036]

[Equation 14] When the output signals are combined in this way, the resistance value of the third volume 10 changes to 0 (Ω) ≦ x ≦ _RA (Ω) by moving the position of the stick 12 left and right,
As shown in Expressions 12 and 13, the balance is adjusted and the sound image feels to be on the left side when x = 0, and x
When = _RA , you will feel like you are on the right side.

Therefore, by using the stick volume 11 and varying the first to third volumes 8, 9 and 10 by interlocking with the stick 12, the sound image is changed as shown in the explanatory view of FIG. Change.

That is, when the position of the stick 12 is set to the front as shown in FIG. 3A, the sound image I is in front of the user U, and when it is right, the sound image I is the user U.
To the right of, to the rear, the sound image I is
The sound image I will be displaced to the left of the user U by moving it to the left and behind.

Although the sound image position is displaced using the stick volume 11 in this embodiment, the first and second volumes 8 and 9 and the third volume 10 are used instead of the stick volume 11. May be replaced with slide volumes, respectively, which makes it easier to insert and output rhythm components in one piece of music.

As described above, according to this embodiment, the following effects are obtained. As it is composed only of analog circuits,
It can be provided at low cost. Since the stick volume 11 is used as the operation means, the user can arbitrarily and speedily change the image position of the sound image in accordance with the music or rhythm. When the position of the stick 12 of the stick volume 11 is set to the center,
Sound can be heard equally from the front area, and a surround feeling can be obtained. In-phase components of the left channel L and the right channel R can be removed. By moving the stick 12 left and right, the sound image can also be moved left and right. Easy to operate with one hand.

[0041]

As described above, according to the present invention, the phase can be manipulated by calculating the analog signals of both the left and right channels, and at that time, the operating means introduced to change the circuit constant is used. By operating it, the position of the sound image can be easily changed freely by 360 degrees with only the two left and right speakers. Moreover, since the circuit used is an analog circuit, it can be provided at low cost.

[Brief description of drawings]

FIG. 1 is a circuit diagram of a sound field localization operating device according to an embodiment of the present invention.

FIG. 2 is a plan view of a stick volume changing a position of a sound image used in the sound field localization operating device according to the embodiment.

FIG. 3 is an explanatory diagram showing a relationship between an operation position of a stick and a sound image position of the stick volume according to the embodiment.

[Explanation of symbols]

 1L, 1R Input amplifier 2L, 2R Signal balance circuit 3L, 3R Common mode signal removal circuit 4L, 4R Buffer amplifier 5L, 5R Mix amplifier 6 Pan 7L, 7R Output amplifier 8 1st volume 9 2nd volume 10 3rd Volume 11 Stick Volume 12 Stick

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[Procedure amendment]

[Submission date] September 29, 1994

[Procedure Amendment 1]

[Document name to be corrected] Drawing

[Name of item to be corrected] Figure 1

[Correction method] Change

[Correction content]

FIG.

Claims (2)

[Claims] 1. An input signal amplifying means provided in each of two left and right input channels, and an original sound signal output from each of the input signal amplifying means is divided into a first original sound signal and a second original sound signal, and , A pair of signal balancing means consisting of first and second volumes for setting the balance amount of the two original sound signals, and buffer means for making the respective first original sound signals output from the respective signal balancing means in opposite phases. An in-phase signal removing means for removing the in-phase component from each of the second original sound signals output from each of the signal balancing means, and only an out-of-phase component; and an output signal of each of the buffer means and the in-phase signal removing means. And a third volume for varying the balance of the left and right signals output from both signal combining means And output signal amplification means for amplifying and outputting left and right signals whose balance has been changed by the third volume, two left and right speakers for outputting output signals of these output signal amplification means as audio information, A sound field localization operating device, comprising: sound image position operating means for operating the first to third volumes to set the sound image position to a predetermined position in front, rear, left and right. 2. The sound field localization operating device according to claim 1, wherein the sound image position operating means comprises a stick volume for operating the first, second and third volumes with one stick.