JPH047000A - Stereophonic sound reproducing device - Google Patents

Abstract

PURPOSE:To attain the reception of a natural imaginary sound image even in a room having much reflecting sound by reproducing a signal with a transfer characteristic of imaginary sound image production convoluted thereon and a signal with a transfer characteristic restoring its characteristic to the former transfer characteristic convoluted thereon. CONSTITUTION:A signal inputted to a signal input means 1 is inputted to an imaginary sound source control means 2 and a sound image control auxiliary means 3. The imaginary sound source control means 2 uses an acoustic transducer 70 so as to realize an effect as if the inputted signal S were reproduced by an imaginary acoustic transducer 80 and applies a transfer characteristic Grf for such the purpose to the signal and outputs the result to an amplifier 60 and the means 3. The means 3 convolutes the transfer characteristic of (1-Grf) to a signal from the means 1 based on a difference signal between inputted two signals and outputs the result to an amplifier 61. Signals outputted from the amplifiers 60, 61 drive the acoustic transducers 70, 71 respectively. Thus, a natural imaginary sound image is received even in a room having much reflecting sound.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a three-dimensional sound reproducing apparatus in which the virtual sound image localization position of an input signal is not limited to the setting location of an acoustic transducer used for reproduction.

2. Description of the Related Art In recent years, efforts have been made to improve the sound quality of audio reproduction and to provide three-dimensional reproduction through signal processing. For example, by controlling the signals input to speakers, we create an auditory phenomenon in which sounds can be heard even from places where there are no speakers, thereby creating a three-dimensional sound field in which sounds arrive from all directions.

An example of a conventional stereophonic sound reproduction device will be described below with reference to the drawings.

FIG. 2 shows a conventional three-dimensional sound reproduction device. In FIG. 2, 1 is a signal input terminal; 2 is a sound image control means that processes the signal so that the arrival characteristics from the virtual sound image position to the listener's ears can be realized by reproducing the real sound source;
40 is a listener, 60 is an amplifier, 70 is an acoustic transducer, 80
is an imaginary acoustic transducer that the listener 40 feels when listening to the signal reproduced by the acoustic transducer.

In order to use the acoustic transducer 70 to achieve an effect as if the input signal S were being reproduced by an imaginary acoustic transducer 80, the transfer characteristics from the acoustic transducer 70 to the ears of the listener 40 must be adjusted. Gf, from the imaginary acoustic transducer 80 to the listener 4
When the transfer characteristic up to 0 is Or, the sound image control means 2 applies Grf (
The signal S.sub.X Since the transfer characteristic from the acoustic transducer 70 to the ear of the listener 40 is Gf, the overall characteristic at the ear of the listener 40 is 5XGr/GfX
Gf=S-Gr, and the listener 40 feels the position of the acoustic transducer 70 at the position of the transfer characteristic Or.

Problems to be Solved by the Invention However, with the configuration of the stereophonic sound reproduction device as described above, the effect can only be achieved in a state without reverberation in which only the direct sound of the signal reproduced from the acoustic transducer 70 can be heard. In a real room where there are many reflected sounds, all the reflected sounds are convolved with the transfer characteristic Grf, resulting in an unnatural sound and a problem in that the effect of clearly localizing the virtual speaker is reduced.

In view of the above problems, the present invention provides a transfer characteristic Gr for virtual sound image generation.
By reproducing both the signal convolved with f and the signal convolved with the transfer characteristic (l-Grf) that returns the transfer characteristic Grf to the initial characteristic, the direct sound becomes the sound convolved with Grf. , and for reflected sounds that arrive at the listening position very densely from all directions, the average acoustic spectrum will be the same as the originally input signal,
Therefore, it is an object of the present invention to provide a three-dimensional sound reproducing device that can provide natural virtual sound image control even in an actual room with reflections.

Means for Solving the Problems In order to solve the above problems, the stereophonic sound reproducing apparatus of the present invention includes a signal input means for inputting a signal, and at least one for determining a sound image localization location of a signal output from the signal input means. a sound image control 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; Each device includes an amplifying means for amplifying power, and an acoustic converting means for converting the output signal of the amplifying means into an acoustic signal.

Operation The present invention reproduces both the signal convoluted with the transfer characteristic Grf for generating a virtual sound image and the signal convolved with the transfer characteristic (1-Grf) that returns the transfer characteristic Grf to its initial characteristic. Three-dimensional sound reproduction in which the acoustic spectrum average of the reflected sounds that arrive at the listening position very densely from all directions is the same as the original input signal, and therefore a natural virtual sound image can be perceived even in an actual room with reflections. This is what the device can achieve.

EXAMPLE A first example of the present invention will be described below with reference to the drawings.

The purpose of this embodiment is to provide a stereophonic sound reproducing apparatus that can sense a natural virtual sound image even in an actual room with many reflected sounds. Hereinafter, a three-dimensional sound reproducing apparatus according to a first embodiment of the present invention will be explained using FIG.

In FIG. 1, a signal input to signal input means 1 is input to virtual sound source control means 2 and sound image control auxiliary means 3. The imaginary sound source control means 2 is an acoustic transducer 8 whose input signal S is imaginary.
0, the sound transducer 7 creates an effect as if it were being played.
This is realized using 0. That is, when the transfer characteristic from the acoustic transducer 70 to the ear of the listener 40 is Gf, and the transfer characteristic from the imaginary acoustic transducer 80 to the listener 40 is Gr, the signal reproduced by the acoustic transducer 70 is Grf (=
The transfer characteristic Gr/Gf 1) is subjected to convolution processing and a signal 5XGrf is output to the amplifier 60 and the sound image control auxiliary means 3. The sound image control auxiliary means 3 receives the input 2
The difference signal between the two signals is lost by the input signal passing through the sound image control means 2 by using a subtraction circuit or by convolving the transfer characteristic of (1-Grf) with the signal input from the signal input means 1. Only the signal components are extracted and output to the amplifier 61. The signals output by the amplifiers 60, 61 drive acoustic transducers 70, 71 to generate sound that reaches the listener 40. The listener 40 is
By listening to the signal emitted from the acoustic transducer 70, one can feel as if a sound image is being reproduced from the imaginary acoustic transducer 80, and furthermore, the acoustic transducer 7
0 and the sound emitted by the acoustic transducer 71 are synthesized in space, resulting in a sound in which the transfer characteristics G r and f have been eliminated. The acoustic transducers 70 and 71 used in this embodiment may be, for example, speakers or headphones.

As described above, according to this embodiment, the signal input means, the sound image control means for determining the sound image localization location of the input signal, and the difference signal between the signal input to the sound image control means and the output signal thereof By providing a sound image control auxiliary means for extracting, an amplification means for power amplifying the output signals of the sound image control means and the sound image control auxiliary means, and an acoustic conversion means for converting each output signal of the amplification means into an acoustic signal, Even in an actual room with many reflected sounds, a natural virtual sound image can be perceived.

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

The purpose of this embodiment is to listen to direct sound by separating the sound emitted from the acoustic transducer, which is direct sound, and the output signal of the sound image control auxiliary means that compensates for the acoustic energy balance of reflected sound. The objective is to enhance the effect of the listener's perception of the false sound source.

FIG. 3 is a block diagram of a stereophonic sound reproducing apparatus according to a second embodiment of the present invention. Components having the same functions as those in FIG. 1 are given 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 temporally separating it from the direct sound or reflecting sound. It gives properties similar to . The output signal of the difference signal processing means 4 is radiated into space via an amplifier 62 and an acoustic transducer 72, and reaches the position of the listener 40.

As described above, according to this embodiment, the output signal of the sound image control means and the difference signal processing means is provided with a difference signal processing means that performs delay processing and/or reverberation processing on the output signal of the sound image control means. , an amplification means, and an acoustic conversion means, the sound controlled by the sound image control means can be easily heard as a direct sound, and the effect of the listener's perception of the false sound source is enhanced.

A stereophonic sound reproducing apparatus according to a third embodiment of the present invention will be described below.

The purpose of this embodiment is to reduce the number of amplifiers and acoustic transducers for reproducing the sound image control means and the difference signal processing means, respectively, 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 designated by the same reference numerals, and detailed explanation thereof will be omitted.

In FIG. 4, reference numeral 5 denotes an adder that adds the signals output by the sound image control means 2 and the difference signal processing means 4 and outputs the result to the amplifier 63. In this way, even if both signals are added and reproduced by the acoustic transducer 73, the correlation between the two signals on the time axis is reduced by the difference signal processing means 4, so the sound image control means 2 outputs The effect of virtual sound image control using signals is hardly hindered.

As described above, according to this embodiment, the number of amplifiers and acoustic transducers is reduced, the system can be simplified, and costs 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 and 10 are signal manual means, 2 and 2° are sound image control means, 3 and 30 are sound image control auxiliary means, and 60° and 61
, 64.65 is an amplification means, 70.71.74.75 is an acoustic transducer, 40 is a listener, and 80.81 is an imaginary acoustic transducer.

In this embodiment, when there are two systems of input signals, the configuration shown in FIG. 1 is provided independently for each system to perform sound image control.

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

The purpose of this embodiment is to effectively perform virtual sound image control using two systems of transfer characteristics even in an actual room with many reflections.

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

First, the signal inputted by the signal input means 1 is inputted to the two sound image control means 21 and 22, and from the virtual sound regenerator 80 where a virtual sound image is created, the transfer characteristics to both ears are determined at the positions of both ears of the listener 40. In order to realize this, signal processing is performed in consideration of the transfer characteristics from the acoustic transducers 77 and 78 to the positions of both ears. The output signals of the two sound image control means 21 and 22 are radiated into space from acoustic transducers 77 and 78 through amplifiers 67 and 68, respectively. Further, the sound image control auxiliary means 3 compares the input signal with the output signals of the two sound image control means 21.22, outputs a signal that is not included in the sound image control means 21.22, and outputs a signal that is not included in the sound image control means 21.22. Acoustic radiation is emitted through the

As described above, according to this embodiment, even in a method of controlling a virtual sound image by focusing on the transfer characteristics to both ears, virtual sound image control is effectively performed even in a room with many reflections.

Effects of the Invention As described above, according to the present invention, a natural virtual sound image can be perceived even in an actual room with many reflected sounds. In addition, by performing time delay processing and 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 is more likely to be heard as a direct sound, thereby eliminating the false sound source. The effect perceived by the listener can be further enhanced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram showing a three-dimensional sound reproducing apparatus according to a first embodiment of the present invention, FIG. 2 is a block diagram showing a conventional three-dimensional sound reproducing apparatus, and FIG. 3 is a block diagram showing a conventional three-dimensional sound reproducing apparatus according to a second embodiment of the present invention. FIG. 4 is a block diagram showing a stereophonic sound reproducing device according to a third embodiment of the present invention, and FIG. 5 shows a stereophonic sound reproducing device according to a fourth embodiment of the present invention. Block Diagram FIG. 6 is a block diagram of a stereophonic sound reproducing apparatus according to a fifth embodiment of the present invention. 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,
60.61.62.63.6465, 66, 67, 68
......Amplifier, 70.71.72.73.74°75, 76, 77, 78...Acoustic transducer. Name of agent Patent attorney Shigetaka Awano 1 person 1 Z No. λ υ 1,000 N @ 81111 Uzai 6 Formerly 1 @ No wholesale assistance means increase Tsune Tomoe τ, ”; 'Pi\8゜Figure 2゛Go\8゜〼Go\e.

Claims (3)

[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 the signal output from the signal input means, a signal input to the sound image control means and the sound image control means a sound image control auxiliary means for extracting a difference signal from the output signal of the sound image control means, an amplification means for power amplifying the output signals of the sound image control means and the sound image control auxiliary means, respectively, and converting the output signal of the amplification means into an acoustic signal. A stereophonic sound reproducing device comprising a sound converting means. (2) Claim comprising a difference signal processing means for performing delay processing, reverberation processing, or both on the output signal of the sound image control auxiliary means and outputting it to the amplification means (
1) The three-dimensional sound reproduction device described above. (3) Difference signal processing means that performs delay processing and/or reverberation processing on the output signal of the sound image control auxiliary means, and adding the output signals of the difference signal processing means and the sound image control means and outputting the result to the amplification means. The stereophonic sound reproducing apparatus according to claim 1, further comprising control signal adding means.