JPH06178399A - Device for calculating sound image localization coefficient - Google Patents

Abstract

PURPOSE:To execute sound image localization with less sound quality deterioration by calculating a signal to be sound pressure difference and time difference which are detected from the response of a reproduction speaker by a detector by means of matrix arithmetic unit. CONSTITUTION:The peak sound pressure difference of target impulse response h5n and h6n is detected by a peak sound pressure difference detector 23 when the speaker is arranged at the position of the target sound image and let it sound and a peak time difference detecting equipment 24 detects time difference at the time of peak sound pressure. The signal to be sound pressure difference and time difference which are detected as above mentioned is generated from reproduction system impulse response h1n-h4n by a peak time difference adjusting equipment 25 and a peak sound pressure difference adjusting equipment 26. Moreover, the signal is inputted to the matrix arithmetic unit 11 as the target characteristic of a sound image localization device and the sound image localization coefficients hLn and hRn are calculated and outputted to a tap setting equipment 12. Then, the difference of tone color generated between the sound image localization device and sound which is reproduced without using the localized sound image is minimized. Thus, the sound image localization coefficient for performing sound image localization with less sound quality deterioration is calculated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound image localization coefficient calculating device for a sound image localization device for reproducing realistic sound in AV (audio / visual) equipment.

[0002]

2. Description of the Related Art In recent years, VTRs have been used in the video and audio fields.
Due to the widespread use of sound, a large screen and realistic sound reproduction are desired in order to enjoy movies at home, and the development of hardware corresponding thereto is desired.

Particularly in the sound of VTR movie software, the Dolby Surround system, in which speakers are arranged laterally or rearward (or a combination thereof) for reproduction, has become popular, as is done in movie theaters. ing.

Separately from this, a sound image localization device for a home TV set or the like so that sound can be heard from the side or the rear without actually placing the speaker on the side or the rear. Is being developed.

A sound image localization device using two reproducing speakers will be described below.

FIG. 9 is a diagram showing a configuration of a conventional sound image localization device and a method of localizing a sound image to the left rear of a listener.

In FIG. 9, 1 is a sound image localization device, 2 is an oscillator that outputs a signal S (t) (t represents continuous time, and indicates that the signal is a time function. The same applies hereinafter),
3 and 4 are FIR filters, 5 is a reproduction speaker placed in front of the listener 8 left front, 6 is a reproduction speaker placed in front of the listener 8 right front, and 7 is placed in rear left of the listener 8. It is a target speaker and hL (t) is the impulse response (F
(IR) The impulse response when the impulse is input from the oscillator 2 to the filter 3, and hR (t) is the impulse response when the impulse is input from the oscillator 2 to the FIR filter 4, and hereinafter, hL (t) and hR (t ) Is referred to as a sound image localization coefficient in the left (L) and right (R) sound image localization apparatus 1. h1 (t) is the response at the position of the speaker 5 and the left ear of the listener 8 (correctly, at the position of the eardrum when an impulse is input to the speaker 5,
The head-related transfer function at the position of the ear canal when performing the measurement (the same applies below) is called the impulse response to explain in the time domain. However, similar results can be obtained even when considered in the frequency domain. Also, a Fourier transform of the impulse response into a frequency characteristic is called a transfer function.), H2 (t) is the impulse response at the position of the speaker 5 and the right ear of the listener 8, and h3 (t) is , Speaker 6 and listener 8
Impulse response at the position of the left ear of the speaker, h4 (t) is the impulse response at the position of the right ear of the speaker 6 and the listener 8,
h5 (t) is the impulse response at the position of the speaker 7 and the left ear of the listener 8, and h6 (t) is the impulse response at the position of the speaker 7 and the right ear of the listener 8.

The operation of the conventional sound image localization apparatus and the sound image localization method will be described with reference to FIG.

In such a configuration, when the signal S (t) from the oscillator 2 is radiated from the target speaker 7, the sound reaching the ear of the listener 8 is (Formula 1) in the left ear L (t). ，

[0010]

## EQU1 ## L (t) = S (t) * h5 (t) In the right ear R (t), (Equation 2),

[0011]

## EQU00002 ## R (t) = S (t) * h6 (t) (where * represents a convolution operation).
Actually, the impulse response of the speaker itself is also convoluted, but this is ignored. Further, it may be considered that the impulse response of the speaker or the like is included in h5 (t) and h6 (t).

Further, the impulse response and the signal S (t) are considered as digital signals whose time is discrete, and L (t) → L (n) R (t) → R (n) h5 (t) → h5 ( n) h6 (t) → h6 (n) S (t) → S (n), the equations of (Equation 1) and (Equation 2) are as follows.

[0013]

[Equation 3]

[0014]

[Equation 4]

Here, N is the impulse response h5 (n), h6
It is the length of (n).

On the other hand, when the signal S (t) is input from the oscillator 2 to the sound image localization device 1, the input signal S (t) is branched into two, which are the FIR filter 3 and the FIR filter 4, respectively.
Is input to the first filter, convolution processing is performed by the FIR filters 3 and 4, and then output from the speakers 5 and 6, respectively. At that time, the sound reaching the listener 8 is the left ear L ′ (t).
Then (Equation 5),

[0017]

[Equation 5] L '(t) = S (t) * hL (t) * h1 (t) + S (t) * hR (t) * h3 (t) In the right ear R' (t), 6),

[0018]

[Equation 6] R ′ (t) = S (t) * hL (t) * h2 (t) + S (t) * hR (t) * h4 (t), and similarly (Equation 7) and By (Equation 8)

[0019]

[Equation 7] L '(n) = S (n) * hL (n) * h1 (n) + S (n) * hR (n) * h3 (n)

[0020]

## EQU8 ## R '(n) = S (n) * hL (n) * h2 (n) + S (n) * hR (n) * h4 (n).

If it is assumed here that sounds are heard from the same direction if the head-related transfer functions are equal (this assumption is generally correct), (Equation 9)

[0022]

## EQU9 ## When L (n) = L '(n), according to (Equation 10) and (Equation 11)

[0023]

[Equation 10] h5 (n) = hL (n) * h1 (n) + hR (n) * h3 (n)

[0024]

When R (n) = R '(n), as shown in (Equation 12),

[0025]

[Equation 12] h6 (n) = hL (n) * h2 (n) + hR (n) * h4 (n), so that the speaker 5 and the speaker 6 can hear the listener 8 from the left rear. To do, (Number 10)
It suffices to determine hL (n) and hR (n) so that and (Equation 12) are satisfied. For example, if (Equation 10) and (Equation 12) are rewritten in the frequency domain representation, the convolution operation is replaced with multiplication, and after that, the impulse response of each is transformed into a transfer function by Fast Fourier Transform (FFT). . Since the impulse responses of the FIR filters 3 and 4 are obtained by measurement except the impulse responses of the FIR filters 3 and 4, the impulse responses of the FIR filters 3 and 4 can be obtained from these two equations (10) and (12).
Can be obtained from It is also possible to express (Equation 10) and (Equation 12) by a matrix formula and determine hL (n) and hR (n) by inverse matrix operation.

HL (n), hR (n) thus determined
By radiating the signals S (n) and hL (n) from the speaker 5 and the convolution of the signals S (n) and hR (n) from the speaker 6, the listener 8 actually Even if the target speaker 7 in the rear is not sounded, it is possible to make the user feel that the sound is coming from behind.

Even if there are three or more reproduction speakers, the sound image can be localized at an arbitrary position by performing the same processing as described above.

The actual convolution operation here is FIR
The filters 3 and 4. A block diagram of the basic configuration of the FIR filters 3 and 4 is shown in FIG. In FIG.
A delay element 3-2 that delays the signal by τ time is connected in series to the input terminal 3-1 that inputs the signal.
To both ends of -2, a multiplier called a tap coefficient and a multiplier 3-3 for multiplying an input signal are connected. Those multipliers 3
The other end of -3 is connected to an adder 3-4 that adds a plurality of input signals, and the adder 3-4 is connected to an output terminal 3-5 that outputs the added signals.

H (n) (n: 0 to N-1) of the multiplier 3-3 is an impulse response having a certain characteristic set as a tap coefficient. Usually, such an FIR filter uses a dedicated LSI such as a DSP (Digital Signal Processor) which performs multiplication and addition at high speed. In the multiplier 3-3, the impulse response h (n) is set as a tap coefficient as shown in the figure, and the delay element 3
The delay time corresponding to the sampling frequency when converting an analog signal to a digital signal is set in -2, and by multiplying and adding and delaying the input signal respectively (Equation 3), (Equation 4) Execute the convolution operation as shown in.

Therefore, by inputting a signal to this FIR filter, the characteristics of the impulse response h (n) are convoluted with the input signal and output. Since the above is the case of the digital signal, the A / A that actually converts the analog signal into the digital signal before this FIR filter is used.
A D converter and a D / A converter for converting a digital signal into an analog signal are necessary after the D converter and are omitted in FIGS. 9 and 10.

Next, a conventional sound image localization coefficient calculation device for a sound image localization device when two reproduction speakers are used will be described.

FIG. 11 is a block diagram showing the configuration of a conventional sound image localization coefficient calculating device.

In FIG. 11, 9-1, 9-2, 9-3, 9-4 are reproduction system characteristic input terminals, 10-1, 10-2 are target characteristic input terminals, 11 is a matrix calculator, and 12 is Tap setting device, 13, 14, 15-1, 15-2,
15-3 and 15-4 are FIR filters, 16 is an impulse generator,
Reference numerals 17 and 18 are adders, 19 and 20 are subtractors, 21 is a feedback controller, and 22-1 and 22-2 are sound image localization coefficient output terminals. Note that h1 (n), h2 (n), h3 (n), h4 (n), h5 (n), h6
(n), hL (n) and hR (n) are h1 shown in FIG.
(t), h2 (t), h3 (t), h4 (t), h5 (t), h6 (t), hL
(t) and hR (t) are converted into discrete expressions.

The operation of the conventional sound image localization coefficient calculating device configured as described above will be described with reference to FIG.

From the reproduction system characteristic input terminals 9-1, 9-2, 9-3, 9-4, reproduction system impulse responses h1 (n), h, which are characteristics of the reproduction system,
Input 2 (n), h3 (n) and h4 (n) respectively, and input target impulse responses h5 (n) and h6 (n) which are target characteristics from target characteristic input terminals 10-1 and 10-2, respectively. Then, all the input signals are input to the matrix calculator 11.

In the matrix calculator 11, the impulse response h1
When (n), h2 (n), h3 (n), and h4 (n) are reproduction system characteristics, the sound image localization coefficient of the sound image localization device such that the impulse responses h5 (n) and h6 (n) are the target characteristics. , That is, (Equation 10), (Equation 12)
Candidates h'L (n), h'R of hL (n), hR (n) that satisfy
(n) is calculated and the reproduction system impulse responses h1 (n), h2 (n),
Tap setter 12 for h3 (n), h4 (n), h'L (n), h'R (n)
Output to.

The tap setting device 12 supplies the FIR filter 13 with an impulse response h'L (n), the FIR filter 14 with an impulse response h'R (n), and the FIR filter 15-1 with an impulse response h1 (n). , Impulse response h to the FIR filter 15-2
2 (n) to impulse response h3 (n) in FIR filter 15-3
And the impulse response h4 (n) is set as a tap coefficient in the FIR filter 15-4.

When the setting of the tap coefficient is completed, the impulse generator 16 outputs an impulse, and the outputted impulse is branched into two and is divided into FIR filters 1 respectively.
The impulses input to 3 and 14 are subjected to convolution processing with the tap coefficients h′L (n) and h′R (n) in the FIR filters 13 and 14, respectively, and output. In addition, FI
The output from the R filter 13 is equivalent to h'L (n), and the output from the FIR filter 14 is equivalent to h'R (n).

Each of these output signals is branched into two, and the output h'L (n) from the FIR filter 13 is input to the FIR filters 15-1 and 15-2, respectively, and the tap coefficient h1 (n) is input. , H2 (n), and convolution processing is performed. The output from the FIR filter 14 is h'R (n)
Are input to FIR filters 15-3 and 15-4, respectively, and convolution processing is performed with tap coefficients h3 (n) and h4 (n), respectively, and output.

The outputs of the FIR filters 15-1 and 15-3 are adders.
FIR filter
The outputs of 15-2 and 15-4 are input to the adder 18 and added and then output. The subtractor 19 receives the outputs of h5 (n) and adder 17 and adds them to h5 (n). The difference between the output of the adder 17 and the output of the adder 18 is input to the subtractor 20, and the output of the adder 18 is input to h6 (n).
The difference between (n) and the output of the adder 18 is output.

The outputs of the subtracters 19 and 20 are input to the feedback controller 21, which subtracts from the preset positive values by the subtracters 19 and 20.
If the absolute value of the input from 20 is large, the command signal is output to the matrix calculator 11 to delay the h5 (n) and h6 (n) by a preset time and then perform the matrix calculation, and again. The matrix operation is performed in the same manner as described above, and the above operation is repeated.

However, in the feedback controller 21, if the absolute value of the input from the subtracters 19 and 20 becomes smaller than the preset positive value, the calculation is stopped, and h'which has already been obtained at that time is obtained. L (n) and h'R (n) are hL
(n), hR (n) outputs a command signal to the matrix calculator 11, and the matrix calculator 11 outputs the feedback controller 21.
According to the instruction of, hL (n) and hR (n) are output terminal 22-
Output from 1 and 22-2.

A similar sound image localization coefficient can be obtained by using an arithmetic operation unit which obtains a coefficient by performing Fourier transform on the impulse response and performing an operation in the frequency domain, instead of the matrix operation unit.

Further, without using the impulse generator 16 and the FIR filters 13 and 14, the impulse response h'L (n),
h'R (n) may be input to the FIR filters 15-1, 15-2, 15-3, 15-4.

As described above, the sound image localization coefficient of the sound image localization device when two reproduction speakers are used is obtained from the reproduction system characteristic and the target characteristic.

The sound image localization coefficient is similarly obtained when three or more speakers are used.

By setting the sound image localization coefficient thus obtained in the sound image localization device and reproducing the sound image, the sound image can be localized at a position where no speaker actually exists, and the actual speaker can be seen by the listener. By localizing the sound image at a position wider than the position of, it is possible to reproduce sound with a sense of spaciousness and presence.

[0048]

However, in the above-mentioned structure, the timbre of the sound image localized by the sound image localization device and the timbre of the sound reproduced from the reproduction speaker without using the sound image localization device are presented to the listener. And there is a difference between
As a result, this is one of the factors of the sound quality deterioration of the localized sound image by the sound image localization device.

In consideration of such a conventional problem, the present invention provides the listener with a tone color of a sound image localized by a sound image localization device and a tone color of a sound reproduced from a reproduction speaker without using the sound image localization device. So that there is no difference between
An object of the present invention is to provide a sound image localization coefficient calculation device that calculates a sound image localization coefficient.

[0050]

According to the present invention, there are provided reproduction system characteristic input means for inputting reproduction system impulse responses in the left and right ears of a listener to a plurality of reproduction speakers as input signals, and a position where a sound image is to be localized. Target characteristic input means for inputting target impulse responses in the left and right ears of the listener with respect to the target speaker actually placed on the target speaker, and the sound in the left and right ears of the listener when the sound is output from the target speaker. A peak sound pressure difference detecting means for detecting a pressure difference, a peak time difference detecting means for detecting a difference in arrival time of sounds reaching the left and right ears of the listener at that time, and one of the plurality of reproduction speakers. Input the respective reproduction system impulse responses in the left and right ears of the listener when the impulse is emitted from the reproduction speaker, and input the input signals. In the signal, the peak time difference adjusting means for adjusting and outputting the delay time so that the difference between the arrival times of the impulses becomes equal to the time difference detected by the peak time difference detecting means, and the output signal from the peak time difference adjusting means is inputted. A sound pressure difference in the input signal, peak sound pressure difference adjusting means for adjusting and outputting the amplitude so as to be equal to the sound pressure difference detected by the peak sound pressure difference detecting means,
The reproducing system impulse response and the output signal from the peak sound pressure difference adjusting means are input, and the calculating means has a calculating means for calculating a coefficient of the sound image localization device from the input signal. Sound image localization such that the reproduction system impulse response in the left and right ears of the listener when the output signal when an impulse is input is reproduced by the plurality of reproduction speakers is equal to the output signal from the peak sound pressure difference adjusting means. It is characterized by outputting the coefficient of the device.

[0051]

According to the present invention, the reproduction system characteristic input means inputs the reproduction system impulse response when a plurality of reproducing speakers are used, and the target characteristic input means inputs the target impulse response as the input signal. , The peak sound pressure difference detecting means detects the sound pressure in the left and right ears of the listener when the sound is output from the target speaker, and the peak time difference detecting means reaches the arrival time of the sound reaching the left and right ears of the listener at that time. Detect the difference between.

The peak time difference adjusting means inputs, as an input signal, respective reproduction system impulse responses in the left and right ears of the listener when an impulse is emitted from one reproduction speaker among the reproduction speakers. The delay time is adjusted and output so that the difference in arrival time becomes equal to the time difference detected by the peak time difference detecting means.

The peak sound pressure difference adjusting means inputs the output signal from the peak time difference adjusting means, and adjusts the amplitude so that the sound pressure difference in the input signal becomes equal to the sound pressure difference detected by the peak sound pressure difference detecting means. Then, the calculation means inputs the reproduction system impulse response and the output signal from the peak sound pressure difference adjustment means, and reproduces the output signal when the impulse is input to the sound image localization device by a plurality of reproduction speakers. At this time, the sound image localization coefficient of the sound image localization device is output so that the reproduction system impulse response in the left and right ears of the listener becomes equal to the output signal from the peak sound pressure difference adjusting means.

[0054]

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a block diagram showing the arrangement of a sound image localization coefficient calculating device according to the first embodiment of the present invention.

In FIG. 1, 23 is a target characteristic input terminal 10-
A peak sound pressure difference detector that detects the difference between the peak sound pressures of the two signals input from 1 and 10-2, 24 is also the two signals input from the target characteristic input terminals 10-1 and 10-2 , A peak time difference detector for detecting the time difference at the time of peak sound pressure, 25 is the peak time difference detection of the time difference at the time of peak sound pressure of two signals input from the reproduction system characteristic input terminals 9-1 to 9-4. A peak time difference adjuster that adjusts the delay time so as to be equal to the time difference input from the device 24, and 26 is a difference in peak sound pressure between the two signals input from the reproduction system characteristic input terminals 9-1 to 9-4. Is a peak sound pressure difference adjuster for adjusting the amplitude so that it becomes equal to the sound pressure difference input from the peak sound pressure difference detector 23, and 27-1 and 27-2 are the reproduction system characteristic input terminals 9-1 to 9-4. Switch that inputs the two signals from and outputs either of them, aL (n), aR (n) Left from peak sound pressure difference regulator 26, a right output signal. Other functional elements similar to those in FIGS. 9 and 11 are indicated by the same numbers and symbols.

The operation of the sound image localization coefficient calculating apparatus according to the first embodiment having the above configuration will be described with reference to FIG.

From the reproduction system characteristic input terminals 9-1, 9-2, 9-3, 9-4, the reproduction system impulse responses h1 (n), h which are the characteristics of the reproduction system.
Input 2 (n), h3 (n), h4 (n), and input the target characteristic input terminal 10-
Target impulse response h5 which is the target characteristic from 1 and 10-2
Input (n) and h6 (n). The input signals are all branched into two, h1 (n) is input to the matrix calculator 11 and the switch 27-1, and h2 (n) is the matrix calculator 11 and the switch 27-1.
-2, h3 (n) is input to the matrix calculator 11 and the switch 27-1, h4 (n) is input to the matrix calculator 11 and the switch 27-2, and h5 (n) is the peak sound pressure difference. It is input to the detector 23 and the peak time difference detector 24, and h6 (n) is also input to the peak sound pressure difference detector 23 and the peak time difference detector 24.

In the peak sound pressure difference detector 23, the input h5
The peak sound pressures of (n) and h6 (n) are calculated, and the difference is output to the peak sound pressure difference adjuster 26. Further, the peak time difference detector 24 finds the time of each of the input h5 (n) and h6 (n) at the peak sound pressure, and outputs the time difference to the peak time difference adjuster 25.

The switch 27-1 inputs h1 (n) and h3 (n),
The switch 27-2 inputs h2 (n) and h4 (n). If you want to localize the sound image to the left of the listener, switch 27
-1 outputs h1 (n), and the switch 27-2 outputs h2 (n). Also, when it is desired to localize the sound image to the right side of the listener, the switch 27-1 sets h3 (n). , And switch 27-2
Outputs h4 (n) respectively. Switch 27-
The signals output from 1 and 27-2 are input to the peak time difference adjuster 25.

In this peak time difference adjuster 25, the delay time is adjusted so that the time difference at the peak sound pressure of the two input signals becomes equal to the time difference input from the peak time difference detector 24, and the adjusted 2 The two signals are output to the peak sound pressure difference adjuster 26. The peak sound pressure difference adjuster 26 adjusts the amplitude so that the difference between the peak sound pressures of the two input signals becomes equal to the sound pressure difference input from the peak sound pressure difference detector 23, and the adjusted two signals are adjusted. Is output to the matrix calculator 11.

Here, one of the output signals from the peak sound pressure difference adjuster 26 is represented by aL (n) and the other is represented by aR (n), and the peak time difference adjuster 25 and the peak sound pressure difference adjuster 26 By adjustment, aL (n) is the result of adjusting h1 (n) or h3 (n), and aR (n) is the result of adjusting h2 (n) or h4 (n).

In the matrix calculator 11, h1 (n), h2 (n), h3
(n), h4 (n), aL (n), aR (n) are input, and the impulse responses h1 (n), h2 (n), h3 (n), h4 (n) are the characteristics of the reproducing system, The sound image localization coefficient of the sound image localization apparatus in which aL (n) and aR (n) are the target characteristics, that is, the left side of Equation 10 is aL (n) and the left side of Equation 12 is aR (n), is satisfied. HL (n), hR (n)
The candidates h′L (n) and h′R (n) of are calculated.

On the other hand, the subtractor 19 receives aL (n) and the output of the adder 17 as (h1 (n) + h3 (n)), and outputs the difference between aL (n) and the output of the adder 17. The subtractor 20 uses aR (n) and the adder 18
Output (h2 (n) + h4 (n)) is input and aR (n) and adder 18
Is output, and other operations are the same as those of the conventional sound image localization coefficient calculation device described with reference to FIG. 11, and finally the sound image localization coefficients hL (n) and hR (n) are Output from output terminals 22-1, 22-2 respectively.

Hereinafter, the peak sound pressure difference detector shown in FIG.
23, the peak time difference detector 24, the peak time difference adjuster 25, and the peak sound pressure difference adjuster 26 will be described respectively.

FIG. 2 is a schematic diagram showing the configuration and operation of the peak sound pressure difference detector.

In FIG. 2, 23-1 and 23-2 are input terminals of the peak sound pressure difference detector, 23-3 is a divider, and 23-4 is an output terminal.

The operation of the peak sound pressure difference detector 23 configured as described above will be described. First, input terminal 23
-Input signal 1 (h5 (n)) is input from -1, input signal 2 (h6 (n)) is input from input terminal 23-2, peak sound pressure A of input signal 1 and peak sound of input signal 2 Pressure B is detected and divider
It is output to 23-3, A / B is performed in the divider 23-3, and the result is output from the output terminal 23-4. In FIG. 2, the input signal 1 and the input signal 2 are schematically represented by a graph in which the horizontal axis represents time t and the vertical axis represents peak sound pressures A and B according to voltage values. Needless to say, when the sound pressure is expressed in decibels, a subtractor is used instead of the divider 23-3 to perform AB.

In this way, the peak sound pressure difference detector 23 detects and outputs the difference between the peak sound pressures of the two input signals.

FIG. 3 is a schematic diagram showing the structure and operation of the peak time difference detector.

In FIG. 3, 24-1 and 24-2 are input terminals of the peak time difference detector, and 24-3 is an output terminal.

The operation of the peak time difference detector 24 configured as described above will be described. First, input terminal 24
-1 receives the input signal 1 (h5 (n)), the input terminal 24-2 receives the input signal 2 (h6 (n)), the input signal 1 has a peak sound pressure time t1 and the input signal 2 Time t2 at peak sound pressure
Is detected, the difference Δt between t1 and t2 is obtained, and the output terminal 24
It is output from -3. Note that, in FIG. 3, the input signal 1 and the input signal 2 are schematically shown as in FIG.

In this way, the peak time difference detector 24 detects and outputs the time difference between the two input signals at the peak sound pressure.

FIG. 4 is a schematic diagram showing the configuration and operation of the peak time difference adjuster.

In FIG. 4, 25-1, 25-2, 25-3 are input terminals of the peak time difference adjuster, and 25-4, 25-5 are output terminals.

The operation of the peak time difference adjuster 25 configured as above will be described. First, input terminal 25
-The input signal 1 (h1 (n), h3 (n)) is input from -1, the input signal 2 (h2 (n), h4 (n)) is input from the input terminal 25-2, and the peak of the input signal 1 The time t'1 at the time of sound pressure and the time t'2 at the time of peak sound pressure of the input signal 2 are detected, and the input signal 3 is output from the input terminal 25-3 (the output Δt from the output terminal 24-3 of FIG. 3). , The time difference Δt is input, and the input signal 2 is changed to (Δt−t′2 + t′1) so that the difference between t′1 and t′2 becomes equal to Δt.
By delaying the input signal 2 so that the time of the peak sound pressure of the input signal 2 is t3, and the result is output terminal
The signal is output from 25-5, and the input signal 1 is output from the output terminal 25-4 as it is.

In this way, the peak time difference adjuster 25 adjusts the time difference between the two input signals at the time of peak sound pressure to be equal to the input time difference and outputs the adjusted signal.

FIG. 5 is a schematic diagram showing the structure and operation of the peak sound pressure difference adjuster.

In FIG. 5, 26-1, 26-2, 26-3 are input terminals of the peak sound pressure difference adjuster, 26-4 is a calculator, 26-5 is a multiplier, and 26-6, 26-7 are It is an output terminal.

The operation of the peak sound pressure difference adjuster 26 configured as above will be described. First, input terminal 26
Input signal 1 (output from output terminal 25-4 in FIG. 4) is input from -1 and input signal 2 (output terminal 2 in FIG. 4 is input from input terminal 26-2.
(Output from 5-5) is input, and the peak sound pressure A'of the input signal 1 and the peak sound pressure B'of the input signal 2 are detected.

The sound pressure difference C is input as an input signal 3 (output A / B from the output terminal 23-4 in FIG. 2) from the input terminal 26-3, and A ', B', C are calculated by the arithmetic unit 26-4. Input to the calculator 26
-4 is the calculation result A '/ (B' · C) is the multiplier 26-5
And the input signal 2 is output to A '/ (B' in the multiplier 26-5.
・ C) is multiplied and output, and the peak sound pressure of the output signal becomes A '/ C, and the peak sound pressure of the input signal 1 is A'.
It becomes equal to the sound pressure difference C between and. The output signal from the multiplier 26-5 is output from the output terminal 26-7, and the input signal 1 is output as it is from the output terminal 26-6.

When the sound image is localized on the left side of the listener, the output from the output terminal 26-6 is aL (n), the output terminal 26 is
The output from -7 is aR (n), and when the sound image is localized to the right of the listener, the output from output terminal 26-6 is aR (n),
The output from the output terminal 26-7 becomes aL (n).

In this way, the peak sound pressure difference adjuster 26 adjusts the difference between the peak sound pressures of the two input signals to be equal to the input sound pressure difference C and outputs the adjusted signal.

As described above, the target impulse responses h5 (n) and h6 (n), which are the target characteristics, are not directly input to the matrix calculator 11, but are reproduced system impulse responses h1 (n) and h3 (n).
Alternatively, the amplitude and delay time of h2 (n) and h4 (n) are adjusted and input to the matrix calculator 11. As a result, when the calculated sound image localization coefficients hL (n) and hR (n) are set in the sound image localization device, a predetermined reproduction speaker is connected, and an impulse is input to the sound image localization device. To localize the sound image to the left side of the listener, the impulse response in the left ear of the listener becomes equal to h1 (n), and the impulse response in the right ear of the listener changes the delay time and amplitude of h2 (n). However, the time delay due to feedback control is ignored. Also, in order to localize the sound image to the right side of the listener, the impulse response in the right ear of the listener is h4.
(n) and the impulse response in the left ear of the hearing is h3
(n) Delay time and amplitude are changed (however,
As with the left localization, the time delay due to feedback control is ignored. The sound image localization coefficient is as follows.

As described above, when the sound is output from the speaker placed at the position where the sound image is desired to be localized, the arrival time difference and the sound pressure difference of the person who has reached the left and right ears of the listener are realized to reach the target position. Sound image localization is not only possible, but when a sound image is localized on the left side of the listener by a sound image localization device, it is reproduced from the left reproduction speaker without using the localized sound image and the sound image localization device. It is possible to minimize the difference in timbre that occurs between different sounds.

When a sound image is localized on the right side of the listener by the sound image localization device, a tone color generated between the localized sound image and the sound reproduced from the reproduction speaker on the right side without using the sound image localization device. It is possible to minimize the difference between. As a result, it is possible to calculate a sound image localization coefficient that minimizes the sound quality deterioration of the localization sound image by the sound image localization device.

In this embodiment, the case where the sound image is localized on the left side of the listener and the case where it is localized on the right side are distinguished. However, regardless of the position of the sound image localization, h1 (n) and h2 (n) are always used.
Alternatively, either h3 (n) or h4 (n) may be input to the peak time difference adjuster 25.

In this embodiment, the output signals from the peak time difference adjuster 25 and the peak sound pressure difference adjuster 26 are both 2.
However, since one of the output signals is equivalent to the output signal from the switch 27-1 or the switch 27-2 from the adjustment method by the peak time difference adjuster 25 and the peak sound pressure difference adjuster 26, The output signal from the switch 27-1 or the switch 27-2, which is equivalent to the output signal, is stopped, and the output signals from the peak time difference adjuster 25 and the peak sound pressure difference adjuster 26 are both one. Switch to 11 27
-1 or the output signal from the switch 27-2 may be branched and input.

In this embodiment, the outputs of the switches 27-1 and 27-2 are input to the peak time difference adjuster 25.
It is also possible to input only one of the outputs of the switches 27-1 and 27-2 and output the input signal itself and the signal in which the delay time of the input signal is adjusted.

Further, in this embodiment, the peak sound pressure difference adjuster 26 is connected after the peak time difference adjuster 25 to adjust the peak time difference and then the peak sound pressure difference. (Embodiment 2 of the invention described in 2), the peak time difference adjuster 25 may be connected after the peak sound pressure difference adjuster 26, and the peak time difference may be adjusted after the peak sound pressure difference is adjusted. Do the same as you did.

Next, a second embodiment of the present invention will be described with reference to the drawings.

FIG. 6 is a block diagram showing the arrangement of a sound image localization coefficient calculating device according to the second embodiment of the present invention.

In FIG. 6, 28 is a target characteristic input terminal 10-
Amplitude frequency characteristic difference detector that detects the difference in amplitude frequency characteristic of the two signals input from 1 and 10-2, and 29 is the two signals input from the reproduction system characteristic input terminals 9-1 to 9-4 The amplitude frequency characteristic difference adjuster that adjusts the amplitude on the frequency axis so that the amplitude frequency characteristic difference of is equal to the amplitude frequency characteristic difference input from the amplitude frequency characteristic difference detector 28, and 30 is a reproduction system characteristic input terminal 9 Switches that input two signals from -1 and 9-4 and output either of them, bL (n), bR (n)
Is an output signal from the amplitude frequency characteristic difference adjuster 29. Other functional elements similar to those in FIG. 1 are indicated by the same numbers and symbols.

The operation of the sound image localization coefficient calculating device in the second embodiment configured as described above will be described with reference to FIG.

From the reproduction system characteristic input terminals 9-1, 9-2, 9-3, 9-4, the reproduction system impulse responses h1 (n) and h which are the characteristics of the reproduction system.
Input 2 (n), h3 (n), h4 (n), and input the target characteristic input terminal 10-
Target impulse response h5 which is the target characteristic from 1 and 10-2
(n) and h6 (n) are input, h1 (n) and h4 (n) are branched into two, and h1 (n), h2 (n), h3 (n) and h4 (n) are matrices. The branched h1 (n) and h4 (n) input to the arithmetic unit 11 are input to the switch 30.

The above h5 (n) and h6 (n) are input to the amplitude frequency characteristic difference detector 28, and the amplitude frequency characteristic difference detector 28 inputs the respective amplitude frequencies of h5 (n) and h6 (n). The characteristic is obtained, and the difference between the respective amplitudes on the frequency axis is output to the amplitude frequency characteristic difference adjuster 29. Switch 30 is h1
(n) and h4 (n) are input, h1 (n) is output when the sound image is localized on the left side of the listener, and h4 (n) is output when the sound image is localized on the right side of the listener. n) output and switch
The signal output from 30 is input to the amplitude frequency characteristic difference adjuster 29.

The amplitude frequency characteristic difference adjuster 29 receives the output from the switch 30 and the output from the amplitude frequency characteristic difference detector 28, and detects the amplitude frequency characteristic difference from the amplitude frequency characteristic of the signal input from the switch 30. With the amplitude reduced on the frequency axis by the amplitude frequency characteristic difference input from the device 28,
The signal input from the switch 30 is output to the matrix calculator 11.

Here, one of the output signals from the amplitude frequency characteristic difference adjuster 29 is represented by bL (n) and the other is represented by bR (n), and when it is desired to localize the sound image to the left side with respect to the listener. Indicates that bL (n) is the same as h1 (n), and bR (n) is the result of adjusting h1 (n) by the adjustment in the amplitude frequency characteristic difference adjuster 29, and To localize the sound image, bR (n) is equivalent to h4 (n), and bL (n) is the result of adjusting h4 (n) by the adjustment in the amplitude frequency characteristic difference adjuster 29. To do.

Next, in the matrix calculator 11, h1 (n), h2 (n), h
When 3 (n), h4 (n), bL (n) and bR (n) are input and the impulse responses h1 (n), h2 (n), h3 (n) and h4 (n) are the characteristics of the playback system , BL (n), bR (n) are target characteristics, the sound image localization coefficient of the sound image localization apparatus, that is, the left side of (Equation 10) is represented by bL (n), (Equation 1
HL (n), h that satisfies the expression in which bR (n) is changed on the left side of 2)
The candidates h'L (n) and h'R (n) of R (n) are calculated, and bL (n) and the output of the adder 17 are input to the subtractor 19 and bL (n) and the adder 17 are input.
Is output to the subtractor 20 and bR (n) and the adder
The output of 18 is input and the difference between bR (n) and the output of the adder 18 is output. Other operations are the same as the operations of the conventional sound image localization coefficient calculation device described using FIG. Sound image localization coefficients hL (n) and hR (n) are output terminals 22-1 and 22 respectively.
Output from -2.

The amplitude frequency characteristic difference detector 28 and the amplitude frequency characteristic difference adjuster 29 will be described in detail below.

FIG. 7 is a block diagram showing the structure of the amplitude frequency characteristic difference detector.

In FIG. 7, 28-1 and 28-2 are input terminals of the amplitude frequency characteristic difference detector, 28-3 and 28-4 are Fourier transformers,
28-5 is a difference extractor and 28-6 is an output terminal.

The operation of the amplitude frequency characteristic difference detector 28 constructed as described above will be described.

First, h5 (n) is input from the input terminal 28-1 and h6 (n) is input from the input terminal 28-2. In the Fourier transformers 28-3 and 28-4, h5 (n) and h5 (n) are input, respectively. h6 (n) is input and Fourier transform is performed, and the resulting amplitude frequency characteristics F (h5 (n)) and F (h6 (n)) are output to the difference extractor 28-5. In this difference extractor 28-5, F (h5 (n)), F (h6
(n)) is input and the difference in amplitude on the frequency axis is extracted, and the result F (h5 (n)) / F (h6 (n)) is output, and the difference extractor 28-5 outputs it. The output is output from the output terminal 28-6.

When the amplitude frequency characteristics are expressed in decibels, the output of the difference extractor 28-5 is F (h5 (n))-F (h6
It goes without saying that (n)).

In this way, the amplitude frequency characteristic difference detector
The difference between the amplitude frequency characteristics of the two input signals is detected and output by 28.

FIG. 8 is a block diagram showing the structure of the amplitude frequency characteristic difference adjuster.

In FIG. 8, 29-1 and 29-2 are input terminals of the amplitude frequency characteristic difference adjuster, 29-3 is a Fourier transformer, 29-4 is a divider, 29-5 is an inverse Fourier transformer, and 29-5. -6 and 29-7 are output terminals.

The operation of the amplitude frequency characteristic difference adjuster 29 configured as described above will be described.

First, from the input terminal 29-1 to a (n) (h1 (n), h
4 (n)) and the amplitude frequency characteristic difference F (h5 (n)) / F (h6) output from the input terminal 29-2 to the output terminal 28-6 of the amplitude frequency characteristic difference detector 28 in FIG. (n)) is input and the input terminal
The a (n) input from 29-1 is branched into two, one is output from the output terminal 29-6, and the other is the Fourier transformer 29.
-3 is input to the Frier converter 29-3, a (n) is input to the FRIE converter 29-3, and the F (a (n)) obtained as a result is output to the divider 29-4.

In the divider 29-4, F (a (n)) and F (h5
(n)) / F (h6 (n)) is input and division is performed, and the result F (a (n)) · F (h6 (n)) / F (h5 (n)) is reversed. It is output to the Fourier transformer 29-5, and F (a
(n)) · F (h6 (n)) / F (h5 (n)) is input and the inverse Fourier transform is performed and the result is F ~ ¹ (F (a (n)) · F (h6)
(n)) / F (h5 (n))) is output, and the output from the inverse Fourier transformer 29-5 is output from the output terminal 29-6.

When the amplitude frequency characteristic is expressed in decibels, the input from the input terminal 29-2 is F (h5 (n))-F.
(h6 (n)), and the output of the divider 29-4 is F (a (n)) + F (h
6 (n))-F (h5 (n)), and the output of the inverse Fourier transformer 29-5 is F ~ ¹ (F (a (n)) + F (h6 (n))-F (h5 (n It goes without saying that it will be))).

When the sound image is localized on the left side of the listener, the output from the output terminal 29-6 is bL (n), and the output terminal 29-6.
The output from -7 is bR (n), and when the sound image is localized on the right side of the listener, the output from output terminal 29-6 is bR (n),
The output from the output terminal 29-7 becomes bL (n).

In this way, the amplitude frequency characteristic difference adjuster
By 29, the amplitude-frequency characteristics of the input signal, the amplitude-frequency characteristics difference of which is subtracted from the amplitude on the frequency axis, and the input signal are output. That is, from one input signal, two signals whose frequency characteristic difference is equal to the input frequency characteristic difference are generated and output. However, one of the output signals is equivalent to the input signal.

As described above, the target impulse responses h5 (n) and h6 (n), which are the target characteristics, are not directly input to the matrix calculator 11, but are reproduced system impulse responses h1 (n) or h4 (n). The sound image localization coefficient hL calculated by inputting the adjusted vibration frequency characteristic of) to the matrix calculator.
For (n) and hR (n), when these are set in the sound image localization device and a predetermined reproduction speaker is connected and an impulse is input to the sound image localization device, the sound image is localized on the left side of the listener. , The impulse response in the left ear of the listener is h1 (n)
And the amplitude frequency characteristic of the impulse response h1 (n) in the right ear of the listener is changed (however, the time delay due to the feedback control is ignored).

In order to localize the sound image to the right side of the listener, the impulse response in the right ear of the listener becomes equal to h4 (n), and the impulse response in the right ear of the listener is the amplitude frequency characteristic of h4 (n). The sound image localization coefficient is such that (the time delay due to feedback control is ignored, as in the case of left-side localization).

As described above, by realizing the difference in the amplitude frequency characteristics of the sound reaching the left and right ears of the listener when the sound is output from the speaker placed at the position where the sound image is to be localized, it is possible to reach the target position. Not only is sound image localization possible, but it is also possible to minimize the difference in timbre that occurs between the sound image localized by the sound image localization device and the sound reproduced from the playback speaker without using the sound image localization device. Becomes As a result, it is possible to calculate a sound image localization coefficient that minimizes the sound quality deterioration of the localization sound image by the sound image localization device.

In this embodiment, the case where the sound image is localized on the left side of the listener and the case where it is localized on the right side are distinguished. However, regardless of the position of the sound image localization, h1 (n) or h4 (n) is always used. Either of these may be input.

Further, in this embodiment, although there are two output signals from the amplitude frequency characteristic difference adjuster, one of the output signals is output from the switch 30 due to the adjustment method by the amplitude frequency characteristic difference adjuster. Since it is equivalent to the output signal of, the output signal of the switch 30 is stopped and the output signal from the amplitude frequency characteristic difference adjuster is set to one and the output of the switch 30 to the matrix calculator is output. The signal may be branched and input.

[0120]

As described above, the sound image localization coefficient calculating device of the present invention has a difference in arrival time of sounds that reach the left and right ears of the listener when the sound is output from the speaker placed at the position where the sound image is desired to be localized. Not only enables the sound image localization to the target position, but also realizes the sound image localization to the target position by realizing the sound pressure difference between the listener and the left and right ears of the listener. When the sound image is localized on the left side, it is possible to minimize the difference in timbre that occurs between the sound image localized and the sound reproduced from the left playback speaker without using a sound image localization device. Becomes

When a sound image is localized on the right side of the listener by the sound image localization device, it occurs between the localized sound image and the sound reproduced from the right reproduction speaker without using the sound image localization device. It is possible to minimize the difference in timbre. As a result, it is possible to calculate a sound image localization coefficient that minimizes the sound quality deterioration of the localization sound image by the sound image localization device.

[Brief description of drawings]

FIG. 1 is a block diagram showing a configuration of a sound image localization coefficient calculating device according to a first embodiment of the present invention.

FIG. 2 is a schematic diagram showing the configuration and operation of the peak sound pressure difference detector of FIG.

FIG. 3 is a schematic diagram showing the configuration and operation of the peak time difference detector of FIG.

FIG. 4 is a schematic diagram showing the configuration and operation of the peak time difference adjuster of FIG.

5 is a schematic diagram showing the configuration and operation of the peak sound pressure difference adjuster of FIG.

FIG. 6 is a block diagram showing a configuration of a sound image localization coefficient calculating device according to a second embodiment of the present invention.

7 is a block diagram showing a configuration of an amplitude frequency characteristic difference detector of FIG.

8 is a block diagram showing a configuration of an amplitude frequency characteristic difference adjuster of FIG.

FIG. 9 is a diagram showing a configuration of a conventional sound image localization device and a method of localizing a sound image to the left rear of a listener.

FIG. 10 is a block diagram showing a basic configuration of an FIR filter.

FIG. 11 is a block diagram showing a configuration of a conventional sound image localization coefficient calculating device.

[Explanation of symbols]

1 ... Sound image localization device, 2 ... Oscillator, 3, 4, 13, 14,
15-1, 15-2, 15-3, 15-4 ... FIR filter, 3-1, 23-
1, 23-2, 24-1, 24-2, 25-1, 25-2, 25-3, 26-1, 26-
2, 26-3, 28-1, 28-2, 29-1, 29-2 ... Input terminal, 3-2
Delay element, 3-3, 26-5 ... Multiplier, 3-4, 17, 18 ... Adder, 3-5, 22-1, 22-2, 23-4, 24-3, 25-4, 25 -5, 26-
6, 26-7, 28-6, 29-6, 29-7 ... output terminals, 5, 6 ... playback speaker, 7 ... target speaker, 8 ... listener,
9-1, 9-2, 9-3, 9-4 ... Playback system characteristic input terminal, 10-1, 10
-2 ... Target characteristic input terminal, 11 ... Matrix calculator, 12 ... Tap setter, 19, 20 ... Subtractor, 21 ... Feedback controller, 23 ... Peak sound pressure difference detector, 23-3, 29-4 ... Division 24 ... Peak time difference detector, 25 ... Peak time difference adjuster, 26 ... Peak sound pressure difference adjuster, 26-4 ... Calculator,
27-1, 27-2, 30 ... Switch, 28 ... Amplitude frequency characteristic difference detector, 28-3, 28-4, 29-3 ... Fourier transformer, 29 ... Amplitude frequency characteristic difference adjuster, 28-5 ... Difference extractor, 29-5 ... Inverse Fourier transformer.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI Technical indication location H04R 3/00 310 7346-5H H04S 1/00 K 8421-5H (72) Inventor Mitsuhiko Serikawa Osaka Prefecture 1006 Kadoma, Kadoma-shi, Matsushita Electric Industrial Co., Ltd. (72) Ryo Tagami, 1006 Kadoma, Kadoma, Osaka Prefecture Matsuda Denki Sangyo Co., Ltd. (72), Mikio Oda, 1006 Kadoma, Kadoma, Osaka Matsushita Sangyo Co., Ltd.

Claims (6)

[Claims] 1. A reproduction system characteristic input means for inputting a reproduction system impulse response in the left and right ears of a listener to each of a plurality of reproduction speakers as input signals, and a target speaker actually placed at a position where a sound image is to be localized. Target characteristic input means for inputting target impulse responses in the left and right ears of the listener as input signals, and a peak sound for detecting a difference in sound pressure between the left and right ears of the listener when sound is output from the target speaker. An impulse is emitted from the pressure difference detection means, the peak time difference detection means for detecting the difference in the arrival times of the sounds reaching the left and right ears of the listener at that time, and the reproduction speaker of one of the plurality of reproduction speakers. Input the reproduction system impulse responses of the left and right ears of the listener as input signals, and Peak time difference adjusting means for adjusting and outputting the delay time so that the difference in arrival time becomes equal to the time difference detected by the peak time difference detecting means, and an input signal from the output signal from the peak time difference adjusting means is inputted. The sound pressure difference at, the peak sound pressure difference adjusting means for adjusting and outputting the amplitude so as to be equal to the sound pressure difference detected by the peak sound pressure difference detecting means, and the reproduction system impulse response and the peak sound pressure difference adjusting means. An output signal and an arithmetic means for calculating a coefficient of the sound image localization apparatus from the input signal, wherein the arithmetic means reproduces the output signal when the impulse is input to the sound image localization apparatus from the plurality of reproduction signals. Image localization device such that the reproduction system impulse response in the left and right ears of the listener when reproduced by the speaker for use becomes equal to the output signal from the peak sound pressure difference adjusting means. Sound image localization coefficient calculation unit and outputs the coefficient. 2. The peak sound pressure difference adjustment means inputs respective reproduction system impulse responses in the left and right ears of a listener to one reproduction speaker of the reproduction speakers, and the sound pressure difference in the input signal is the sound pressure difference. The amplitude is adjusted and output so as to be equal to the sound pressure difference detected by the peak sound pressure difference detecting means, and the peak time difference adjusting means is
Input the output signal from the peak sound pressure difference adjusting means, the difference in the arrival time of the impulse in the input signal, the delay time is adjusted and output so as to be equal to the time difference detected by the peak time difference detecting means, and output, The computing means inputs the reproduction system impulse response and the output signal from the peak time difference adjusting means, calculates a coefficient of the sound image localization device from the input signal, and further the computing means outputs the output of the sound image localization device. A coefficient of the sound image localization device is output so that the reproduction system impulse response becomes equal to the output signal from the peak time difference adjusting means in the left and right ears of the listener when the signal is reproduced by the plurality of reproducing speakers. The sound image localization coefficient calculating device according to claim 1. 3. The peak time difference adjusting means inputs the reproduction system impulse response in one of the left and right ears of a listener to one reproduction speaker of the reproduction speakers as an input signal, and the peak time difference detecting means. The peak sound pressure difference adjusting means inputs the output signal from the peak time difference adjusting means, reduces the sound pressure difference detected by the peak sound pressure difference detecting means, and outputs it. Also, the arithmetic means inputs a signal equivalent to the signal input to the reproduction system impulse response and the peak time difference adjustment means and an output signal from the peak sound pressure difference adjustment means, and the coefficient of the sound image localization device is input from the input signal. Further, the calculating means calculates the left and right of the listener when the output signal of the sound image localization device is reproduced by the plurality of reproduction speakers. Of the reproduction system impulse response at the ear, one outputs a coefficient of the sound image localization device such that one becomes equal to the signal input to the peak time difference adjusting means and the other becomes equal to the output signal from the peak sound pressure difference adjusting means. The sound image localization coefficient calculation device according to claim 1. 4. The peak sound pressure difference adjustment means inputs a reproduction system impulse response in one of the left and right ears of a listener to one reproduction speaker of the reproduction speakers as an input signal, and the peak sound pressure difference is adjusted. The peak time difference adjusting means inputs the output signal from the peak sound pressure difference adjusting means and outputs it after delaying it by the time difference detected by the peak time difference detecting means. The calculation means inputs the reproduction system impulse response, a signal equivalent to the signal input to the peak sound pressure difference adjustment means, and an output signal from the peak time difference adjustment means, and the calculation means further includes a sound image localization device. Of the reproduction system impulse response in the left and right ears of the listener when the output signal of the above is reproduced by the plurality of reproduction speakers. 3. A sound image localization apparatus coefficient which is equal to the signal input to the pressure difference adjusting means and is equal to the output signal from the peak time difference adjusting means. Or 3
The sound image localization coefficient calculation device described. 5. A reproduction system characteristic input means for inputting reproduction system impulse responses in the left and right ears of a listener to each of a plurality of reproduction speakers as input signals, and a target speaker actually placed at a position where a sound image is to be localized. Target characteristic input means for inputting target impulse responses in the left and right ears of the listener as input signals, and an amplitude for detecting a difference in amplitude frequency characteristics between the left and right ears of the listener when a sound is output from the target speaker. The frequency characteristic difference detection means and the respective reproduction system impulse responses in the left and right ears of the listener with respect to one of the reproduction speakers are input as input signals, and the difference between the amplitude frequency characteristics in the input signals is the above-mentioned. The output is adjusted so that it becomes equal to the amplitude frequency characteristic difference detected by the vibration frequency characteristic difference detecting means. A vibration frequency characteristic difference adjusting means, and inputting the reproduction system impulse response and the output signal from the vibration frequency characteristic difference adjusting means, and a calculating means for calculating the coefficient of the sound image localization device from the input signal, The calculation means is such that the reproduction system impulse response in the left and right ears of the listener when the output signal of the sound image localization device is reproduced by the plurality of reproduction speakers is equal to the output signal from the amplitude frequency characteristic difference adjustment means. A sound image localization coefficient calculation device, which outputs the coefficient of a sound image localization device. 6. The amplitude frequency characteristic difference detecting means inputs the reproduction system impulse response in one of the left and right ears of a listener to one reproducing speaker among the reproducing speakers as an input signal, and the amplitude frequency characteristic difference is detected. The amplitude is reduced or increased by the amplitude frequency characteristic difference detected by the detecting means and output, and the arithmetic means is a signal equivalent to the reproduction system impulse response and the input signal to the amplitude frequency characteristic difference adjusting means. The output signal from the amplitude frequency characteristic difference adjusting means is input, the coefficient of the sound image localization device is calculated from the input signal, and the calculation means reproduces the output signal of the sound image localization device with the plurality of reproduction speakers. Of the reproduction system impulse response in the left and right ears of the listener,
A coefficient of the sound image localization device is output such that one becomes equal to the signal input to the amplitude frequency characteristic difference adjusting means and the other becomes equal to the output signal from the amplitude frequency characteristic difference adjusting means. Item 5. The sound image localization coefficient calculation device according to item 5.