JPH1023600A - Sound image localization device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a sound image localization device which can localize a sound image at a fixed point through simple arithmetic processing regardless of the turn of the headphones. SOLUTION: Head part transmission characteristics from forward obliquely left below (Ch1), front obliquely right below (Ch2), backward obliquely right below (Ch3), backward obliquely left below (Ch4), forward obliquely left above (Ch5), forward obliquely right above (Ch6), backward obliquely right above (Ch7), and backward obliquely left above (Ch8) are supplied to FIR filters of Ch1 to Ch8, and the direction of a virtual sound image position viewed from the headphones 3 is found from an azimuth sensor provided at the peak part of the headphones 3 and a virtual sound image position set with a joy stick; and the gain corresponding to the direction is set in the FIR filters of the said Ch1 to Ch8 to localize the sound image. At the same time, a distance feeling is given by properly setting the output tap of a delay line provided in front of the FIR filters.

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 apparatus for localizing a sound image of a musical tone output from an electronic musical instrument or audio equipment at a predetermined position.

[0002]

2. Description of the Related Art Electronic musical instruments and audio equipment increase the sense of realism of output musical sounds. And output timing are controlled. A “point” in this space is referred to as a virtual sounding position, and a virtual space area (where a virtual musical instrument is located) in which a musical sound is imaged as being sounded is referred to as a sound image.

[0003] In general stereo headphones at present, a musical sound is supplied to left and right speakers at a predetermined balanced volume so that the sound image of the musical sound is localized. However, since the headphones are mounted on the listener's head, when the listener moves his or her head, the speakers of the headphones also follow the headphone, and the sound image also moves with the above control alone. To cope with this, a headphone system has been proposed in which the position of a sound image does not change even if the head is moved by detecting that the listener has moved his / her head and controlling the tone characteristics output to the left and right speakers. (Japanese Unexamined Patent Publication No.
No. -44500).

[0004]

However, in the above-mentioned headphone system, a filter for the left ear and a filter for the right ear are provided, respectively, and a parameter of a response characteristic corresponding to the direction of the headphone is read out according to the direction of the headphone, and the read filter is used as the filter. Since the setting is controlled, it is necessary to store parameters corresponding to many virtual sounding positions in the parameter memory. For this reason, the sound image cannot be localized accurately unless a large parameter memory is provided.
There is a disadvantage that the parameters must be read out each time the listener moves his or her head.

SUMMARY OF THE INVENTION It is an object of the present invention to provide a sound image localization apparatus capable of localizing a sound image at a fixed point even when a listener moves his or her head by simple arithmetic processing.

[0006]

According to the first aspect of the present invention, there is provided a headphone having left and right separate speakers, an azimuth detecting means for detecting an orientation of the headphone, and a sound for setting a virtual sounding position of a musical sound. Position setting means, a plurality of filter means for convoluting a tone signal with tone transmission characteristics from a plurality of directions to both ears, and a headphone based on the setting contents of the sounding position setting means and the detection contents of the direction detecting means. Relative position data including at least the direction of the virtual sounding position is determined. Characteristic setting means for setting the gains of the plurality of filter means based on the determined relative position data, and output from the plurality of filter means. Synthesizing means for synthesizing a signal and supplying the synthesized signal to a speaker of the headphone.

The invention of claim 2 of the present application is characterized in that the azimuth detecting means is constituted by a magnet compass provided in the headphones and a sensor for detecting a pointing direction thereof.

According to a third aspect of the present invention, there is provided a headphone having left and right separate speakers, azimuth detecting means for detecting the direction of the headphone, sounding position setting means for setting a virtual sounding position of a musical sound, A plurality of filter means for convolving a tone signal with a tone transmission characteristic from both directions to the two ears, a delay means for delaying an input tone signal by a predetermined time and supplying the tone signal to the plurality of filter means, The relative position data including at least the direction of the virtual sounding position with respect to the headphones is determined based on the setting contents of the means and the detection contents of the azimuth detecting means, and the gains and the gains of the plurality of filter means are determined based on the determined relative position data. A characteristic setting unit for setting the delay time of each of the delay units; and a signal output from the plurality of filter units. Characterized by comprising a composite output means for supplying to the speaker of the headphone.

According to the invention of claim 4 of the present application, the delay means is provided with a plurality of output sections each having a different delay time set, and the characteristic setting means sets the delay time for each of the plurality of output sections. Means for performing

The invention of claim 5 of this application is characterized in that the characteristic setting means is means for setting a gain for each of the plurality of output units for each filter means.

According to the first aspect of the present invention, there are provided a plurality of filter means for convoluting and calculating a tone signal with a tone transmission characteristic from a plurality of directions to both ears, and setting the headphone direction and sounding position detected by the azimuth detecting means. The gain of each filter unit is set based on relative position data (for example, direction and distance) determined based on the virtual sounding position set by the unit. As described above, since the sound image can be localized only by setting the filter means corresponding to a plurality of directions in advance and setting the gain of each filter means in accordance with the localization direction, various parameters are read out each time. Compared to the setting method, sound image localization and localization movement can be performed by simple processing, and processing suitable for real-time sound image localization control corresponding to head movement can be performed.

According to the second aspect of the present invention, since the azimuth detecting means is constituted by a magnet compass and a sensor for detecting the direction indicated by the magnet compass, the azimuth of the headphones can be detected with an inexpensive configuration.

According to a third aspect of the present invention, a plurality of filter means for convolving a tone signal with a tone transmission characteristic from a plurality of directions to both ears, and a delay means for delaying a tone signal input to the plurality of filter means And the gain of each filter means and the delay time of the delay means based on the headphone direction detected by the azimuth detection means and the relative position data determined based on the virtual sounding position set by the sounding position setting means. Is set. As described above, the sound image can be localized only by providing the filter means and the delay means corresponding to a plurality of directions in advance and setting the gain of each filter means and the delay time of the delay means in accordance with the localization direction and the distance. Because it is possible, sound image localization and localization movement are possible with simple processing compared to the method of reading and setting various parameters each time, and processing suitable for real-time sound image localization control corresponding to head movement is possible It is.

According to the fourth aspect of the present invention, a plurality of output units having different delay times are provided in the delay means, so that a tone signal corresponding to a direct sound or an initial reverberation sound can be supplied to the filter means. Realistic sound image localization becomes possible.

According to the fifth aspect of the present invention, different gains are set for a plurality of tone signals supplied with different delay times, thereby enabling clearer sound image localization.

[0016]

FIG. 1 is a diagram showing a configuration of a headphone system according to an embodiment of the present invention. The headphone system supplies a tone signal generated by an electronic musical instrument 1 as a sound source to stereo headphones 3 via a sound image localization unit 2. An azimuth sensor 4 is provided at the top of the headphone 3, and the azimuth sensor 4 can detect which direction the headphone 3, that is, a listener wearing the headphone is facing. The content detected by the azimuth sensor 4 is input to the coefficient generator 5. A joystick 6 and a setting button 7 are connected to the coefficient generator 5. The joystick 6 is used to designate a virtual sounding position of a musical tone generated by the electronic musical instrument 1. The virtual sounding position is not relative to the headphones 3 worn by the listener and moves, but is set as an absolute position in the space. The setting button 7 is a button for setting an azimuth (an angle with north being 0 degree) when the listener wearing the headphones 3 faces the virtual wall 8 described later. In addition, a front direction register 5a and a virtual sounding position register 5b are set in the coefficient generator 5 corresponding to these operators.

FIG. 2 is a diagram illustrating a sound image localization method of the headphone system. FIG. 3 is a diagram showing a configuration of the sound image localization unit 2. In FIG. 3, the sound image localization unit 2 includes eight channels of FIR filters 15 (15L, 15R) in parallel. These eight channels Ch1 to Ch8
Respectively correspond to the directions of to in FIG.
That is, the Ch1 FIR filters 15L and 15R are:
Transfer characteristics of musical tones from the direction (position) of FIG. 2 (A) to the left ear and the right ear (head acoustic transfer function: HRTF)
Is an FIR filter that performs convolution operation on a musical tone signal.
Similarly, the Ch2 to Ch8 FIR filters are also shown in FIG.
This is an FIR filter that performs convolution calculation of a musical tone signal with musical tone transmission characteristics from the direction of to to the left and right ears. As described above, the symbol “〜” in FIG. 2A indicates the front direction of the listener, that is, the direction with respect to the headphones 3. When the listener changes his or her head, the direction of the symbol “〜” changes accordingly.

On the other hand, the joystick 6 is an operator for setting a virtual sounding position of a musical tone generated by the electronic musical instrument 1 as described above. Virtual sound position in this embodiment from the headphones 3 to the distance z ₀ virtual wall surface 8
The coordinates on the plane 8 are x, with the origin at the intersection of the perpendiculars from the headphones 3.
Expressed in y-coordinate. When the joystick 6 is operated rightward, the x coordinate of the virtual sounding position increases, and when the joystick 6 is operated leftward, the x coordinate of the virtual sounding position decreases. When the joystick 6 is operated upward, the y coordinate of the virtual sounding position increases, and when the joystick 6 is operated downward, the y coordinate of the virtual sounding position decreases. In FIG. 2A,
Assuming that the virtual sounding position of the musical tone is set to the point 9 on the virtual wall surface 8 and the headphones 3 are in the illustrated direction, the direction of the virtual sounding position is one of the above basic directions.
, And α1, α2, α5, and α6.
Accordingly, the angles α1, α1 are applied to the gain multipliers 12, 13 of Ch1, Ch2, Ch5, Ch6 in FIG.
2, α5, α6, a gain that mainly captures a direct sound (preceding sound) is given to the other channels, and a gain that mainly captures an early reflection sound (following sound) corresponding to the angle is provided to the other channels. By giving the sound, the sound image can be localized at the point 9 in the headphones 3. When the direction of the headphone 3 changes, the angle between the point 9 and the headphone 3 also changes. At this time, angles α1, α2,
Since α5 and α6 are calculated and the gains corresponding to the calculated α5 and α6 are calculated, the sound image of the musical sound is always localized at the virtual sounding position 9 which is an absolute position in space no matter which direction the headphone wearer faces. become. If the virtual sounding position 9 is moved by operating the joystick 6, new angles α1, α2, α5, α
6 is calculated, and the localization moves.

In this description, only the case where the virtual sounding position is near the front of the headphones 3 has been described.
1, Ch4, Ch5, and Ch8, angles α1, α4,
α5, α8 are calculated and the corresponding gain is calculated. When the virtual sounding position is on the right side of the headphones 3, Ch is calculated.
2, Ch3, Ch6, and Ch7, angles α2, α3,
α6 and α7 are calculated and the corresponding gain is determined.
When the virtual sounding position is behind the headphones 3, the angle α with respect to Ch3, Ch4, Ch7, and Ch8.
3, α4, α7, α8 are calculated and the corresponding gain is calculated. When the virtual sounding position is above the headphones 3, the angle α with respect to Ch5, Ch6, Ch7, Ch8
5, α6, α7, α8 are calculated and the corresponding gain is calculated. When the virtual sounding position is below the headphone 3, the angle α with respect to Ch1, Ch2, Ch3, Ch4
1, α2, α3, α4 are calculated, and the corresponding gain is determined.

Although the virtual sounding position 9 can be set only on the virtual wall surface 8 in this embodiment, it may be set at any point in the space. In this case, the joystick 6 can be set to three-dimensional coordinates.

The operator for setting the virtual sounding position 9 is not limited to the joystick 6, but may be an operator for relatively increasing / decreasing coordinate values similar to the joystick 6, or directly inputting coordinate values such as a numeric keypad. The virtual sounding position may be set graphically in an image of a wall or space displayed on the monitor. Further, the setting switch 7 for resetting the direction toward the virtual wall surface 8 may be similarly set to a graphic.

The configuration of the sound image localization unit 2 will be described with reference to FIG. A tone signal input from the electronic musical instrument 1 is converted into a digital signal by the A / D converter 10. If the electronic musical instrument 1 is a digital musical instrument and outputs musical sounds as digital signals, the A / D converter 1
A signal may be directly input to the delay line 11 by skipping 0. The delay line 11 is composed of a multi-stage shift register, and sequentially shifts the input digital tone signal. This delay line 1
1. Two taps are provided at an arbitrary position (register) 1 and the two taps (preceding sound tap, succeeding sound tap)
, The delayed signal (preceding sound, succeeding sound) is taken out. The tap position is determined by a tap position coefficient input from the coefficient generator 5. Of the two taps, a signal extracted from a tap near the input end of the delay line 11 is called a preceding sound, and a signal extracted from a tap far from the input end is called a subsequent sound. The preceding sound corresponds to the direct sound, and the following sound corresponds to the early reflection sound. Preceding sound is C
The subsequent sound is input to the gain multipliers 12 of h1 to Ch8, and the following sound is input to the gain multipliers 13 of Ch1 to Ch8. Two taps of delay line 11 and gain multiplier 1
By appropriately setting the gains 2 and 13, a sense of distance and a sense of front and back of the sound image can be obtained.

For example, if the gap between the preceding sound and the following sound is reduced by shortening the tap interval, the sense of distance can be reduced, and the sound image can be localized closer. On the contrary, the difference between the preceding sound and the following sound is increased. Then, the sense of distance increases, and the sound image can be localized far. However, the difference between the preceding sound and the following sound is 2
Do not exceed 0 ms. If the difference exceeds 20 ms, the listener will recognize the sound as another sound.
Also, when the level difference between the preceding sound and the following sound (the difference between the gain of the gain multiplier 12 and the gain of the gain multiplier 13) is increased, the sound image is easily localized in the front, and the level difference between the preceding sound and the following sound is increased. When is reduced, the sound image can be easily localized backward.

Gain multipliers 12 and 13 for Ch1 to Ch8
Are input from the coefficient generator 5. The preceding sound signal and the following sound signal multiplied by the gain are added by the adder 14 and input to the FIR filter 15. In other words, the reason for taking out two signals of the preceding sound signal and the succeeding sound signal by delaying one musical sound signal is that the same musical sound signal is heard with a small time difference, and the level difference causes a sense of distance and a distance between front and rear. In order to get out. The FIR filter 15 is provided with two systems of a left ear filter 15L and a right ear filter 15R in parallel. Ch1 FIR filter 15
L simulates the sound when the musical sound is heard to the left ear from the direction of FIG. 2A by the head acoustic transfer function, and the FIR filter 15R of Ch1 outputs
The sound when heard from the direction of (A) to the right ear is simulated by the head-related transfer function. Similarly, Ch
FIR filter 15L, FIR filter 1 of 2-Ch8
5R simulates the transmission of musical tones from both directions to the left and right ears using the head acoustic transfer function.

If the direction of the virtual sounding position is a direction intermediate between these basic directions, the coefficient generation unit 5
Calculates the angle between the four directions surrounding the direction of the virtual sounding position among the directions of and the gain and delay line 1 corresponding to the angle, as shown in FIG.
A coefficient for determining one tap is given to the gain multipliers 12 and 13 and the delay line 11 of each channel. When the sound volume is not changed even when the sound image localization position in the headphones 3 changes, all the gain multipliers 1 are used.
The logarithmic total value of the gains given to 2, 13 is 1, but a special effect may be obtained by changing the total gain depending on the sound image localization position.

The signals output from the FIR filters 15L of the respective channels are added and synthesized by an adder 16L. The signals output from the FIR filters 15R of the respective channels are added and synthesized by an adder 16R. The digital music signal thus synthesized is added to the D / A converter 17.
Is converted to an analog signal, amplified by the amplifier 18, and then output to the headphones 3.

FIG. 4 is an external view of the headphones 3.
FIG. 5 is a configuration diagram of the azimuth sensor 4 attached to the top of the headphones 3. Both earpieces of the headphones 3 have built-in small speakers, and receive left and right analog tone signals output from the amplifier 18 respectively. An orientation sensor 4 is provided at the top of the arch. The direction sensor 4 is housed in a cylindrical case 28 and includes a compass 20 and photo sensors 25, 26,
27. The compass 20 has a spherical magnet body 21 accommodated in a spherical transparent acrylic case 22, and a gap between the spherical magnet body 21 and the inner wall surface of the transparent acrylic case 22 is filled with a liquid 23. This liquid 23 is colorless and transparent. The spherical magnet body 21 accommodates a plate-like magnet 21a in the center, a space 21c in the upper part, and a weight 21b in the lower part, in order to always maintain the vertical relationship with gravity in the liquid 23 and to point in the north-south direction. have. Thereby, as shown in FIG.
That is, no matter what direction the headphone 3 is oriented, the spherical magnet body 21a rotates and swings in the transparent acrylic case 20 such that a specific portion always points to the north and the weight 21b faces the direction of gravity. . The spherical magnet body 21 floats in the liquid 23 in the transparent acrylic case 22,
The rotation and swing can be performed in the transparent acrylic case 22 without friction.

The surface of the spherical magnet body 21 is colored with blue and red gradations as shown in FIG.
The blue gradation is colored in a meridian shape so that its density indicates the azimuth as shown in FIGS.
The density of blue decreases as you rotate from north to east to south to west to north. That is, the density (thinness) of blue represents the azimuth angle (clockwise angle with north being 0 degree). The red gradation is shown in Fig. (C), (D).
As shown in FIG. 5, the density is colored in a weft line so as to indicate the inclination angle, and the higher the transparent acrylic case 20 is inclined downward, the higher the density of red appears. Actually, the red gradation and the blue gradation are formed on the same spherical surface, and both colors are mixed.

In FIG. 5, photo sensors 25 to 27 are provided toward the side surface of the compass 20. The photo sensor 25 is a sensor for detecting the density of blue, and the photo sensors 26 and 27 are sensors for detecting the density of red. The photo sensor 25 is directed from the front of the headphones 3 to the side of the compass 20, the photo sensor 26 is directed from the right of the headphones 3 to the side of the compass 20, and the photo sensor 27 is directed from the rear of the headphones 3 to the compass 20. Is oriented to the side.

Each of the photo sensors 25, 26 and 27 is shown in FIG.
It has a configuration shown in FIG. An LED 30 and a photodiode 32 are provided toward the compass 20, and
An optical filter that allows only a predetermined color to pass is provided on the front surfaces of the ED 30 and the photodiode 32. LED30
Is continuously lit by the battery 31 and irradiates the surface of the spherical magnet body 21 of the compass 20. In addition, the photodiode 32 changes its resistance value by receiving the reflected light of the light emitted from the LED 30 on the surface of the spherical magnet body 21. The photodiode 32 is connected to the amplifier 33. The amplifier 33 amplifies the detection value of the photodiode 32 and inputs the amplified value to the LPF 34. The LPF 34 removes a minute vibration component from the detected value, extracts only the head movement as an operation, and outputs it to the coefficient generator 5.

The photo sensor 25 is mounted on the compass 20 from the front side.
By detecting the blue density of the spherical magnet body 21 of FIG. 9, based on the relationship between the detected density value and the azimuth angle shown in FIG.
It is possible to detect which direction the headphones 3 are facing. Further, the photo sensor 26 detects the red color of the spherical magnet body 21 from the right side surface, thereby obtaining the state shown in FIG.
Can be detected based on the relationship between the detected density value and the inclination angle shown in FIG. Further, the photo sensor 27 is connected to the spherical magnet 2 from the rear side.
By detecting the red color, it is possible to detect how much the headphones 3 are facing upward based on the relationship between the density detection value and the elevation angle shown in FIG.

By inputting these detected contents to the coefficient generator 5, the coefficient generator 5 can calculate in which direction and distance the virtual sounding position set by the joystick 6 is viewed from the headphones 3. The tap position of the delay line 11 and the gains of the gain multipliers 12 and 13 of Ch1 to Ch8 for realizing the direction and distance in a signal processing manner are calculated and output to the sound image localization unit 2.

The use of the geomagnetic sensor as the azimuth sensor has the following advantages over other sensors such as a gyro sensor. Even if the head is tilted and turned, no deviation or error occurs, so that stable sound image localization can be realized even when used for headphones of an electronic piano that performs by moving the upper body. Since the geomagnetism is always stable, once calibration (setting of the positional relationship) with a device serving as a sound source, such as an electronic musical instrument or AV equipment, is performed,
Thereafter, there is no need to take it again at the start of use or during use, and it is not necessary to move the apparatus thereafter. Also, it is cheaper than other direction sensors such as a gyro.

The responsiveness to the rotation of the head can be adjusted by adjusting the viscosity of the liquid floating the compass magnet. The transmission of the detected contents to the coefficient generator 5 may be wired or wireless. When performing wirelessly,
Although a battery is used as a power source, the battery may be charged.
For example, a charging function may be provided in a holder on which headphones are placed, and charging may be performed while the headphone is placed on the holder. In the case of a wired connection, signals and power can be transmitted and received via an audio cable of headphones.

FIGS. 10 and 11 are flowcharts showing the operation of the coefficient generator 5. In FIG. 10, when the operation of this apparatus starts, first, various registers are initialized. 0 degree data is input to the front direction register 5a. That is, the front (virtual wall surface 8) of the headphones 3 is assumed to face true north. Then, 0,0 is set as the x, y coordinates in the virtual sounding position register 5b. That is, it is set so that the virtual sounding position is located in front of the headphones 3. Thereafter, the setting button 7 is turned on (s2) or the joystick 6 is operated (s3).
Wait until there is. When the setting button 7 is turned on (s
2) The direction of the direction sensor 4 at that time (photo sensor 2
5 is detected (s4), and the direction is stored in the front direction register 5a (s5). On the other hand, when the joystick 6 is operated, the x and y coordinates of the virtual sounding position register 5b are rewritten according to the operation (s6). That is, when the joystick 6 is operated left and right, the value of the x coordinate is increased or decreased according to the operation, and when the joystick 6 is operated up or down, the value of the y coordinate is increased or decreased according to the operation.

FIG. 11 shows a timer interrupt operation.
This operation is a localization position control operation performed once every several tens of milliseconds. First, the detection values of the three photo sensors 25, 26, 27 built in the direction sensor 4 are read (s11). Then, the direction (azimuth) and inclination of the headphones 3 are detected based on the detected values (s12, s).
13). This data, the heading data, and the virtual sound source z ₀
Then, a direction and a distance to the virtual sounding position are calculated based on the x and y coordinates (s14). Gain and delay line 1 given to each channel based on this direction and distance
1 are determined (s15) and transmitted to the sound image localization unit 2 (s16).

The calculation of the gain, tap position, and the like may be calculated by using a predetermined arithmetic expression based on the calculated direction and distance. Coefficients corresponding to various directions and distances are stored as a table. Then, an appropriate one of the information may be read out. Since the data amount of this coefficient table is extremely small as compared with the table in which the transfer characteristic parameters of the FIR filter corresponding to a plurality of distances and directions are stored, the memory capacity is small even in this case.

[0038]

As described above, according to the first aspect of the present invention, a sound image is localized only by providing filter means corresponding to a plurality of directions in advance and setting the gain of each filter means in accordance with the localization direction. Therefore, compared to the method of reading and setting various parameters each time, it is possible to perform sound image localization and localization with simple processing, and processing suitable for real-time sound image localization control corresponding to head movement is possible. It is possible.

According to the second aspect of the present invention, since the azimuth detecting means is constituted by a magnet compass and a sensor for detecting the indicated direction, the azimuth of the headphones can be detected with an inexpensive configuration.

According to the third aspect of the present invention, filter means and delay means corresponding to a plurality of directions are provided in advance, and only the gain of each filter means and the delay time of the delay means are set in accordance with the localization direction and the distance. Since the sound image can be localized, the sound image localization and the movement of the localization are possible by simple processing, compared with a method of reading and setting various parameters each time, and real-time sound image localization control corresponding to the movement of the head The processing suitable for is possible.

According to the fourth aspect of the present invention, a plurality of output units having different delay times are provided in the delay means, so that a tone signal corresponding to a direct sound or an initial reverberation sound can be supplied to the filter means. Realistic sound image localization becomes possible.

According to the fifth aspect of the present invention, different gains are set for a plurality of tone signals supplied with different delay times, thereby enabling clearer sound image localization.

[Brief description of the drawings]

FIG. 1 is a block diagram of a sound image localization apparatus according to an embodiment of the present invention.

FIG. 2 is a diagram illustrating a sound image localization method of the sound image localization apparatus.

FIG. 3 is a block diagram of a sound image localization unit of the sound image localization apparatus.

FIG. 4 is an external view of headphones of the sound image localization apparatus.

FIG. 5 is a configuration diagram of an azimuth sensor provided in the headphones.

FIG. 6 is a diagram showing a state when the azimuth sensor is inclined.

FIG. 7 is a view for explaining coating of a spherical magnet body of the same direction sensor.

FIG. 8 is a configuration diagram of a photo sensor provided in the same direction sensor.

FIG. 9 is a diagram showing a relationship between a density detection value of a photosensor of the same direction sensor and each direction and inclination.

FIG. 10 is a flowchart showing the operation of a coefficient generation unit of the sound image localization apparatus.

FIG. 11 is a flowchart showing the operation of a coefficient generation unit of the sound image localization apparatus.

[Explanation of symbols]

2… Sound image localization section 3… Headphones 4… Azimuth sensor 5
... Coefficient generation unit, 5a... Front direction register, 5b... Virtual sounding position register, 6... Joystick, 7... Setting button, 11.
12, 13: gain multiplier, 15L, 15R: FIR filter, 16L, 16R: adder, 20: compass, 2
1: spherical magnet body, 21a: plate magnet, 21b: weight, 2
1c: Space, 23: Liquid, 25, 26, 27: Photosensor, 28: Case 30: LED, 32: Photodiode, 35: Filter

──────────────────────────────────────────────────続 き Continued on the front page (51) Int.Cl. ⁶ Identification number Agency reference number FI Technical display location H04S 7/00 H04S 7/00 F

Claims (5)

[Claims] 1. Headphones having left and right separate speakers, azimuth detecting means for detecting the direction of the headphones, sounding position setting means for setting a virtual sounding position of a musical sound, and musical sounds to both ears from a plurality of directions A plurality of filter means for convolving a tone signal with transfer characteristics, and calculating relative position data including at least a direction of the virtual sounding position with respect to headphones based on the setting contents of the sounding position setting means and the detection contents of the direction detecting means. A characteristic setting unit that sets gains of the plurality of filter units based on the determined relative position data; and a synthesis unit that synthesizes signals output from the plurality of filter units and supplies the signals to the headphone speaker. A sound image localization device, comprising: output means. 2. The sound image localization apparatus according to claim 1, wherein the azimuth detecting means includes a magnet compass provided in the headphones and a sensor for detecting a pointing direction. 3. Headphones having left and right separate speakers, azimuth detecting means for detecting the direction of the headphones, sounding position setting means for setting a virtual sounding position of a musical tone, and musical sounds to both ears from a plurality of directions. A plurality of filter means for convolving a tone signal with a transfer characteristic, a delay means for delaying an input tone signal by a predetermined time and supplying it to the plurality of filter means, a setting content of the sounding position setting means and the azimuth detection The relative position data including at least the direction of the virtual sounding position with respect to the headphones is determined based on the detection content of the means, and the gains of the plurality of filter means and the delay time of the delay means are determined based on the determined relative position data. A characteristic setting unit for setting each of the signals; and a signal output from the plurality of filter units, and synthesizing the signals output from the headphones. A sound image localization apparatus comprising: a synthesis output unit that supplies the sound image localization to a car. 4. The delay unit has a plurality of output units each having a different delay time set therein, and the characteristic setting unit is a unit for setting a delay time for each of the plurality of output units. Item 3. The sound image localization device according to Item 3. 5. The sound image localization apparatus according to claim 4, wherein said characteristic setting means is means for setting a gain for each of said plurality of output units for each filter means.