JP2715628B2 - Stereophonic sound reproducer - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a stereophonic sound reproducing apparatus in which a localization position of an input signal is not limited to a setting position of an acoustic transducer used for reproduction.

2. Description of the Related Art In recent years, stereophonic reproduction by signal processing has been attempted while improving the sound quality of audio reproduction. For example, a signal input to a speaker is controlled to create an auditory phenomenon in which sound can be heard even in a place where no speaker exists, thereby realizing a three-dimensional sound field in which sound comes from all directions.

Hereinafter, an example of a conventional stereophonic sound reproducing device will be described with reference to the drawings.

FIG. 2 shows a conventional stereophonic sound reproducing apparatus.
In FIG. 2, 1 is a signal input terminal, 2 is a sound image control means for processing a signal so as to realize the arrival characteristic from the position of the virtual sound image to the ear of the listener by reproducing a real sound source, and 40 is a sound image control means. The listener, 60 is an amplifier, 70 is an acoustic converter, and 80 is a imaginary acoustic converter which the listener 40 feels by listening to the signal reproduced by the acoustic converter.

In order to realize an effect as if the input signal S is reproduced by the imaginary acoustic transducer 80 by using the acoustic transducer 70, the transfer characteristic from the acoustic transducer 70 to the ear of the listener 40 must be adjusted. Gf, and when the transfer characteristic from the imaginary acoustic transducer 80 to the listener 40 is Gr, the signal reproduced by the acoustic transducer 70 becomes GR at the position of the ear of the listener 40. 2
Outputs to the amplifier 60 a signal S × Grf obtained by subjecting the input signal S to convolution processing with the transfer characteristic of Grf (= Gr / Gf), and the acoustic converter 70 reproduces the signal S × Grf. Since the transfer characteristic from the acoustic transducer 70 to the ear of the listener 40 is Gf, the listener 40
The total characteristic at the ear position is S × Gr / Gf × Gf = S · Gr, and the listener 40 feels the position of the acoustic transducer 70 at the position of the transfer characteristic Gr.

However, in the configuration of the three-dimensional sound reproduction device as described above, the effect can be realized only in a state without reverberation where only the direct sound of the signal reproduced from the sound converter 70 can be heard. However, in a real room having many reflected sounds, the transfer characteristic Grf is convoluted with all the reflected sounds, which is unnatural, and there is a problem that the effect of clearly locating the imaginary speaker is reduced.

The present invention has been made in view of the above problems, and has a transfer characteristic Gr
By reproducing both the signal in which f is convolved and the signal in which the transfer characteristic (1-Grf) for restoring the transfer characteristic Grf to the initial characteristic is reproduced, the direct sound is the sound in which Grf is convolved. For the reflected sound that arrives at the listening position from all directions very densely, the average of each acoustic spectrum is the same as the originally input signal, and therefore, the natural virtual sound image control has reflection. It is an object of the present invention to provide a three-dimensional sound reproducing device that can be sensed even in an actual room.

Means for Solving the Problems To solve the above problems, a stereophonic sound reproducing apparatus according to the present invention comprises a signal input means for inputting a signal and at least one sound image localization location of a signal output from the signal input means. Two sound image control means, a sound image control auxiliary means for extracting a difference signal between a signal input to the sound image control means and an output signal of the sound image control means, and an output signal of the sound image control means and the sound image control auxiliary means. The apparatus includes an amplifying unit for amplifying power, and an acoustic converting unit for converting an output signal of the amplifying unit into an acoustic signal.

The present invention reproduces both the signal in which the transfer characteristic Grf for generating the virtual sound image is convolved and the signal in which the transfer characteristic (1-Grf) for returning the transfer characteristic Grf to the initial characteristic is convolved. Acoustic sound reproduction of the reflected sound arriving at the listening position from all directions very closely becomes the same as the originally input signal, so that a natural virtual sound image can be perceived even in an actual room with reflection. The device can be realized.

Embodiment 1 Hereinafter, a first embodiment of the present invention will be described with reference to the drawings.

An object of the present embodiment is to provide a stereophonic sound reproducing apparatus that can sense a natural virtual sound image even in an actual room having many reflected sounds. Hereinafter, a stereophonic sound reproducing apparatus according to the first embodiment of the present invention will be described with reference to FIG.

In FIG. 1, a signal input to a signal input unit 1 is input to a virtual sound source control unit 2 and a sound image control auxiliary unit 3.
The imaginary sound source control means 2 is an acoustic transducer whose input signal S is imaginary.
80 as if it were being reproduced
It is realized using. That is, the listener from the sound transducer 70
Assuming that the transfer characteristic from the ear 40 is Grf and the transfer characteristic from the imaginary acoustic transducer 80 to the listener 40 is Grf, the signal reproduced by the acoustic transducer 70 is Grf at the position of the listener 40's ear. The input signal S is convolved with a transfer characteristic of Grf (= Gr / Gf1) so that the signal S × Grf is amplified by the amplifier 6.
0 and output to the sound image control assisting means 3. The sound image control auxiliary means 3 uses a subtraction circuit for the difference signal between the two input signals, or convolves the transfer characteristic of (1-Grf) with the signal input from the signal input means 1,
Only the signal component lost by the input signal passing through the sound image control means 2 is extracted and output to the amplifier 61. amplifier
The signals output by 60 and 61 generate sound reaching the listener 40 by driving the sound transducers 70 and 71. Listener
By listening to the signal radiated from the acoustic transducer 70, the user can feel as if a sound image is being reproduced from the imaginary acoustic transducer 80.
The sound radiated from the sound transducer 70 and the sound transducer 71 is synthesized in space, and becomes a sound in which the transfer characteristic Grf is eliminated. As the acoustic converters 70 and 71 used in this embodiment, for example, speakers or headphones may be used.

As described above, according to the present embodiment, signal input means,
Sound image control means for determining a sound image localization location of an input signal; sound image control auxiliary means for extracting a difference signal between a signal input to the sound image control means and its output signal; and sound image control means and sound image control auxiliary means. By providing amplification means for power-amplifying each output signal and acoustic conversion means for converting each output signal of the amplification means into an acoustic signal, a natural image of a false sound can be sensed even in an actual room having many reflected sounds. Is what you can do.

Next, a stereophonic sound reproducing apparatus according to a second embodiment of the present invention will be described.

The purpose of the present embodiment is to separate the sound radiated from the acoustic transducer, which is a direct sound, from the output signal of the sound image control auxiliary means for compensating for the acoustic energy balance of the reflected sound and the acoustic properties, so that the direct sound is received. The effect is to increase the effect of the listener perceiving the imaginary sound source.

FIG. 3 is a block diagram of a stereophonic sound reproducing apparatus according to a second embodiment of the present invention. Those having the same functions as those in FIG. 1 are denoted by the same reference numerals.

In FIG. 3, the difference signal processing means 4 performs time delay processing or reverberation generation processing on the signal output from the sound image control auxiliary means 3, thereby separating the signal from the direct sound temporally or reflecting the reflected sound. It has a property close to. The output signal of the difference signal processing means 4 is radiated to the space via the amplifier 62 and the acoustic transducer 72, and reaches the position of the listener 40.

As described above, according to the present embodiment, the output signal of the sound image control auxiliary means is provided with the difference signal processing means for performing the delay processing and / or the reverberation processing, and the output signals of the sound image control means and the difference signal processing means are provided. , The sound controlled by the sound image control means is easily heard as a direct sound, and the effect that the listener perceives the imaginary sound source is enhanced.

Hereinafter, a three-dimensional sound reproducing apparatus according to a third embodiment of the present invention will be described.

The purpose of this embodiment is to reduce the number of amplifiers and sound transducers for reproducing each of the sound image control means and the difference signal processing means,
An object of the present invention is to realize a stereophonic sound reproducing apparatus with a simple system and low cost.

FIG. 4 is a block diagram of a stereophonic sound reproducing apparatus according to a third embodiment of the present invention. Components having the same functions as those in FIG. 3 are denoted by the same reference numerals, and detailed description thereof will be omitted.

In FIG. 4, reference numeral 5 denotes an adder for adding signals output from the sound image control means 2 and the difference signal processing means 4 and outputting the added signal to the amplifier 63. In this way, the sound transducer is added by adding both signals.
Even if the signal is reproduced at 73, the correlation between the two signals on the time axis is reduced by the difference signal processing means 4, so that the effect of the virtual sound image control by the signal output from the sound image control means 2 is almost hindered. There is nothing.

As described above, according to the present embodiment, the number of amplifiers and acoustic transducers is reduced, the system can be simplified, and the cost can be reduced.

FIG. 5 is a block diagram of a stereophonic sound reproducing apparatus according to a fourth embodiment of the present invention.

In FIG. 5, 1, 10 are signal input means, 2, 20 are sound image control means, 3, 30 are sound image control auxiliary means, 60, 61, 64, 65 are amplification means, 70, 71, 74, 75 are sound conversion. , 40 is a listener, and 80 and 81 are imaginary sound transducers.

In this embodiment, when there are two input signals, the first
The configuration shown in the figure is provided independently, and the sound image is controlled.

Hereinafter, a stereophonic sound reproducing apparatus according to a fifth embodiment of the present invention will be described.

An object of the present embodiment is to effectively perform the virtual sound image control even in an actual room where there are many reflections in the virtual sound image control using the transfer characteristics of two systems.

FIG. 6 shows a block diagram of a stereophonic sound reproducing apparatus according to a fifth embodiment of the present invention.

First, the signal input by the signal input means 1 is input to the two sound image control means 21 and 22, and the transfer characteristic to the both ears from the imaginary sound reproducer 80 in which a virtual sound image is created is calculated based on the position of both ears of the listener 40. Therefore, signal processing is performed in consideration of transfer characteristics from the acoustic transducers 77 and 78 to the positions of both ears. Output signals of the two sound image control means 21 and 22 are respectively supplied to amplifiers 67 and 68.
Through the acoustic transducers 77 and 78 to the space. The sound image control auxiliary means 3 compares the input signal with the output signals of the two sound image control means 21 and 22, outputs a signal not included in the sound image control means 21 and 22, and outputs an amplifier 66 and an acoustic converter 76. Sound is emitted through the

As described above, according to the present embodiment, the control of the virtual sound image by paying attention to the transfer characteristics to both ears and the virtual sound image control are effectively performed even in a room with many reflections.

Effect of the Invention As described above, according to the present invention, it is possible to sense a natural image of a virtual sound even in an actual room where there are many reflected sounds.
Further, by performing the time delay processing and the reverberation generation processing on the signal output from the sound image control auxiliary means by the difference signal processing means, the sound controlled by the sound image control means becomes easy to be heard as a direct sound, and the imaginary sound source is reduced. The effect perceived by the listener can be further enhanced.

[Brief description of the drawings]

FIG. 1 is a block diagram showing a stereophonic sound reproducing device according to a first embodiment of the present invention, FIG. 2 is a block diagram showing a conventional stereophonic sound reproducing device, and FIG. 3 is a block diagram showing a second embodiment of the present invention. FIG. 4 is a block diagram showing a stereophonic sound reproducing apparatus according to a third embodiment of the present invention. FIG. 5 is a block diagram showing a stereophonic sound reproducing apparatus according to a fourth embodiment of the present invention. FIG. 6 is a block diagram of a stereophonic sound reproducing apparatus according to a fifth embodiment of the present invention. DESCRIPTION OF SYMBOLS 1 ... Signal input means, 2 ... Sound image control means, 3 ... Sound image control auxiliary means, 4 ... Difference signal processing means, 5 ... Control signal addition means, 60,61,62,63,64,65, 66,67,68 …… Amplifier, 7
0,71,72,73,74,75,76,77,78 ... Acoustic transducer.

Claims (3)

(57) [Claims] 1. A signal input means for inputting a signal, at least one sound image control means for determining a sound image localization location of a signal output from the signal input means, a signal input to the sound image control means, and the sound image Sound image control assisting means for extracting a difference signal from the output signal of the control means, amplifying means for power-amplifying the output signals of the sound image control means and the sound image control assisting means, respectively, and converting the output signal of the amplifying means into an acoustic signal. A stereophonic sound reproduction device comprising: a sound conversion unit for converting. 2. A stereoscopic apparatus according to claim 1, further comprising a difference signal processing means for performing delay processing and / or reverberation processing on an output signal of the sound image control auxiliary means and outputting the processed signal to an amplification means. Sound reproduction device. 3. A difference signal processing means for performing delay processing and / or reverberation processing on an output signal of the sound image control auxiliary means, and an output signal of the difference signal processing means and the sound image control means are added to an amplification means. 3. The stereophonic sound reproducing apparatus according to claim 1, further comprising control signal adding means for outputting.