JPH0614400A - Sound field controller - Google Patents

Abstract

PURPOSE:To increase an expanse sensation in a music assembly hall by a simple constitution by varying a delay time of either stereophonic signal to be branched from an effect sound signal, delayed and generated, a long with time. CONSTITUTION:A stereophonic modulating means 32 consists of an internal RAM or an external RAM of a digital signal processor, and at every sampling period of either signal of digital signals generated by an effect sound generating means 31, data are stored in plural addresses, respectively. Subsequently, by a stereophonic signal modulation control means 33, the data is read out of the stereophonic modulating means 32, as delaying the sampling period. Accordingly, since Rch of the stereophonic signal varies slowly a delay time, a correlation in each time of the left and the right signals due to a fact that the delay time is fixed as before can be lowered. In such a way, an expanse sensation of a stereo of an effect sound can be increased. Also, an expanse sensation of an initial reflected sound and a reverberation sound can be increased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION The present invention provides a feeling of expanse of a music venue.
The present invention relates to a sound field control device that can be enhanced with a simple configuration.

[0002]

2. Description of the Related Art FIG. 13 is a diagram showing stereo formation obtained by delaying a sound effect processed in monaural in a conventional sound field control device. In the sound field control device shown in the figure, the stereo input signals Lch and Rch are added and combined, and the combined signal is formed as a direct sound into a sound effect such as an initial reflected sound and a reverberant sound, and the sound effect is generated. It is divided into two, one is delayed and the levels are adjusted respectively to form stereo output signals Lch and Rch.

[0003]

However, in the conventional sound field control device, since the delay of the left and right signals of the formed stereo signal is constant, there is a left-right correlation and it is difficult to obtain a natural sense of expanse. There is. Furthermore, a signal (L +) obtained by adding and combining two stereo signals Lch and Rch.
When generating early reflections and reverberations from (R),
Since + R) is monaural, its output signal has a strong correlation, that is, the characteristic peculiarity of reverberant sound is inaudible to the ear, and therefore there is a problem that the expansiveness is lacking.

Therefore, an object of the present invention is to provide a sound field control device capable of obtaining a natural spread of a sound effect in view of the above problems.

[0005]

In order to solve the above problems, the present invention provides a sound field control device for generating a sound effect signal such as an initial reflected sound signal and a reverberation signal from a direct sound signal, The delay time of one stereo signal generated by branching and delaying from the sound effect signal is changed with time. The delay time for delaying the direct sound signal to generate the initial reflection sound signal and the reverberation sound signal of the sound effect signal is changed with time. The delay time of one stereo signal generated by branching and delaying from the sound effect signal is changed with time, and the direct sound signal is delayed to generate an initial reflected sound signal and a reverberation sound signal of the sound effect signal. The delay time may be changed with time.

[0006]

According to the sound field control device of the present invention, the left-right correlation can be weakened by changing the delay time of one of the stereo signals generated by branching and delaying the sound effect signal, thereby making the left-right correlation weak. The sense of expansiveness of the stereo will be enhanced. Further, by delaying the direct sound signal and changing the delay time for generating the initial reflection sound signal and the reverberation sound signal of the sound effect signal with time, the spread feeling of the initial reflection sound and the reverberation sound is enhanced. . A variable delay time of one stereo signal generated by branching and delaying from the sound effect signal and delaying the direct sound signal to generate an initial reflected sound signal of the sound effect signal and a reverberation sound signal By changing the delay time with time, it is possible to obtain the spread feeling of the stereo signal and the spread feeling of the initial reflected sound and the reverberation sound.

[0007]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a diagram showing a sound field control device according to an embodiment of the present invention. The sound field control device shown in the figure includes an adding unit 1 that adds and combines the stereo signals Lch and Rch,
A / D converter 2 (Analog to Digit) for converting the combined signal added by the adding means 1 from analog to digital
tal Converter) and an internal R used to form a signal digitized by the A / D converter 2 into a sound effect.
Digital signal processing device 3 having a program built in AM and ROM, and (Digital Signal Processor) external RAM 4 used in the digital signal processing device 3.
A microcomputer 5 for controlling the digital signal processing device 3; and D / A converters 6 and 7 (Digital to Analog Convert) for converting the signal processed by the digital signal processing device 3 into an analog signal as a stereo output signal.
er) is included.

FIG. 2 is a diagram showing the configuration of the sound field control apparatus according to the first embodiment of the present invention. As shown in the figure, the sound field control device configured in the digital signal processing device 3 is
A sound effect generating means 31 for generating a digital signal from the D converter 2 into a sound effect described later, and a delay of one signal for Rch into which the sound effect generated by the sound effect generating means 31 is branched into two. Stereo modulation means 32 for modulating
A stereo modulation control means 33 for controlling the stereo modulation of the stereo modulation means 32; a level adjustment means 34 for adjusting the level of the output signal of the effect sound generation means 31 as Lch; and an output signal of the stereo modulation means 32. It includes a level adjusting means 35 for adjusting the level as Rch. Next, the stereo modulation means 32 and the stereo modulation control means 33 will be described.

FIG. 3 is a diagram showing the storage of sound effects, and FIG.
FIG. 7 is a diagram showing a flowchart of a storage order of sound effects. As shown in the figure, the stereo modulation means 32
Is composed of the internal RAM or the external RAM 4 of the digital signal processing device 3, and outputs the digital signal generated by the sound effect generating means 31 to the address A at every sampling cycle.
1, A2, A3, ..., An are data D (1),
D (2), D (3), ..., D (n) are stored. Here, D (1) is the latest data and data (n) is the oldest, which is stored as shown in FIG. Such a memory is obtained as follows. First, in step 1, the constant i = 1 is set, and in step 2, the data D (i) of the address Ai is set to the address A.
Replace the data D (i + 1) with i + 1. After completion of this replacement, the constant i is incremented by 1 in step 3, and the above process is repeated until i = n in step 4. Then, in step 5, the data D (1) is input to the address A1. Next, the stereo signal modulation control means 33 reads data from the stereo modulation means 32 as follows.

FIG. 5 is a diagram showing a flow chart for explaining the modulation of a stereo signal. Before the description of this figure, assuming that the sampling frequency is 44.1 KHz, one cycle is about 0.0226 ms. In steps 11 to 13, the counter (not shown) starts counting the period number Δi of the sampling signal, and the data D (23) at the address A23 is read from the internal RAM or the external RAM 4. Here, the data D (23) is 22 with respect to D (1).
Although the sampling cycle is delayed, when converted into time, ΔT becomes ΔT = 0.0226 ms × 22 = 0.497 ms. If ΔT is 1 ms or more, binaural hearing is generally lost, so the range should be within this range.

The data D (23) at the address A23 is continuously output by Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time. In steps 14 to 16, similarly, the period number Δi of the sampling signal is similarly started, and the data D (19) at the address A19 is read from the internal RAM or the external RAM 4.

The data D (19) at the address A19 is continuously output for Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time. In steps 17 to 19, similarly, the period number Δi of the sampling signal is similarly started, and the data D (15) at the address A15 is read from the internal RAM or the external RAM 4.

The data D (15) at the address A15 is continuously output for Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time. In steps 20 to 22, similarly, the period number Δi of the sampling signal is similarly started, and the data D (19) at the address A19 is read from the internal RAM or the external RAM 4.

The data D (19) at the address A19 is continuously output as Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time. In steps 23 to 25, similarly, the period number Δi of the sampling signal is similarly started, and the data D (23) at the address A23 is read from the internal RAM or the external RAM 4.

The data D (23) at the address A23 is continuously output as Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time. Similarly, in steps 26 to 28, the number of cycles Δi of the sampling signal is similarly started, and the data D (27) at the address A27 is read from the internal RAM or the external RAM 4.

The data D (27) at the address A27 is continuously output as Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time. In steps 29 to 31, similarly, the number of cycles Δi of the sampling signal is similarly started, and the data D (31) at the address A31 is read from the internal RAM or the external RAM 4.

The data D (31) at the address A31 is continuously output for Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time. In steps 32 to 34, similarly, the period number Δi of the sampling signal is similarly started, and the data D (34) at the address A34 is read from the internal RAM or the external RAM 4.

The data D (34) at the address A34 is continuously output for Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time. The time required for the above processing is 11.3 ms × 8 = 90.4 ms. In other words, as shown in FIG. 3, the data D (23) at the address A23, that is, the data D (23) delayed by about 0.497 ms from the latest data (1) is about 11.3 ms.
Data is output with the delay time shifted by 0.0226ms x 4 = 0.0904ms for each cycle, and the cycle is 90.4ms.
Is.

Therefore, since the Rch of the stereo signal changes the delay time gently, it becomes possible to lower the correlation between the left and right signals at each time due to the fixed delay time as in the conventional case, and the natural spread is achieved. It becomes possible to give. The case where the delay time is changed in a certain cycle has been described above, but it is not necessary to have the periodicity as described below.

FIG. 6 is a diagram showing a flow chart for explaining the modulation of another stereo signal. Step 4 shown in this figure
At 0, the stereo modulation control means 33 has a random number generator (not shown), and α = 0, 1,
Random numbers of 2, 3, and 4 are generated. In step 41, the address Ai of the data D is calculated as Ai = 15 + α × 4 by using the random number.

In step 42, counting of the number of periods Δi of the sampling signal is started. Step 43
At, the data D at the address Ai is read from the internal RAM or the external RAM 4 and is continued until Δi = 500 as shown in step 44. The above process is repeated. Thus, since the delay time changes randomly as compared with the above, it is possible to further reduce the correlation between the left and right signals and enhance the spread feeling.

In summary, assuming that the address A from which data is read out, A = Ao + α × K; α: random number, K: constant. In the above description, numerical values are used for easy understanding, but the present invention is not limited to this.

Although the delay at the time of forming the stereo signal is variable in the above, the reverberation sound felt when the residual sound output from the effect sound generating means 31 is heard has a peculiar habit or improperness. There is naturalness. This occurs for the same reason as described above, as will be described below. FIG. 7 is a diagram showing a configuration of a sound effect generating means in the sound field control device according to the second embodiment of the present invention. As shown in this figure, A /
Initial delay modulating means 311 for initially delaying the signal from the D converter 2 as a direct sound and modulating the initial delay;
An initial reflected sound generation means 312 for generating an initial reflected sound based on the signal delayed by the initial delay modulation means 311;
A reverberation sound means 313 for generating a reverberation sound based on the signal delayed by the initial delay modulation means 311; an addition means 314 for synthesizing outputs of the initial reflected sound generation means 312 and the reverberation sound means 313; Delay modulation means 311
And delay modulation control means 315 for controlling the modulation of the delay time of the output signal of.

FIG. 8 is a diagram for explaining the sound field generated by the sound field control device. As shown in the figure, for the direct sound, the initial reflected sound generating means 312 converts the direct sound to the T
After one hour, the early reflection sound is generated, and the reverberation sound means 31
3 produces a reverberant sound T2 after the direct sound.
Since T1 and T2 are fixed, the initial reflected sound and the reverberant sound generated by the initial reflected sound generation unit 312 and the reverberation sound unit 313 have a strong correlation with the direct sound. The sound field is
Since the relationship with the direct sound is originally weak, it is necessary to weaken the above correlation.

FIG. 9 is a diagram showing the structure of the initial delay modulation means shown in FIG. As shown in the figure, the initial delay modulation means 31
A time τ (for example, about 1 m
A variable multiplier is provided for each s) and its multiplication factor is ao, a1,
Let them be a2, a3 and a4. Similarly, the time τ (about 1 ms) is centered on the delay time T2 of the initial delay modulator 311.
A variable multiplier is provided for each of the multiplication coefficients bo, b1, b2
, B3 and b4.

FIG. 10 is a diagram showing a flow chart for changing the multiplication count of the initial delay modulation means. The initial delay modulation means 311 is controlled by the delay modulation control means 315 as follows, and as shown in the figure, in steps 51 to 53, counting of the number of periods Δi of the sampling signal is started. Multiplication coefficients a2 = 1 and ao = a1 = a3 = a4
Set to = 0. These multiplication coefficients are continuously Δi = 5
00, that is, converted into time, setting continues for 500 × 0.0226 ms = 11.3 ms.

Similarly, in steps 54 to 56, counting of the period number Δi of the sampling signal is started. Multiplication coefficients a1 = 1 and ao = a2 = a3 = a4 =
Set to 0. These multiplication coefficients are continuously Δi = 50
0, that is, in terms of time, the setting continues to be 500 × 0.0226 ms = 11.3 ms.

In steps 57 to 59, counting of the number of periods Δi of the sampling signal is started. The multiplication coefficients ao = 1 and a1 = a2 = a3 = a4 = 0 are set.
These multiplication coefficients are continuously set by Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time.

In steps 60 to 62, counting of the number of periods Δi of the sampling signal is started. The multiplication coefficients a1 = 1 and ao = a2 = a3 = a4 = 0 are set.
These multiplication coefficients are continuously set by Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time.

In steps 63 to 65, counting of the number of periods Δi of the sampling signal is started. The multiplication coefficients a2 = 1 and ao = a1 = a3 = a4 = 0 are set.
These multiplication coefficients are continuously set by Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time.

In steps 66 to 68, counting of the number of periods Δi of the sampling signal is started. The multiplication coefficients a3 = 1 and ao = a1 = a2 = a4 = 0 are set.
These multiplication coefficients are continuously set by Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time.

In steps 66 to 68, counting of the number of periods Δi of the sampling signal is started. The multiplication coefficients a3 = 1 and ao = a1 = a2 = a4 = 0 are set.
These multiplication coefficients are continuously set by Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time.

In steps 69 to 71, counting of the number of periods Δi of the sampling signal is started. The multiplication coefficients a4 = 1 and ao = a1 = a2 = a3 = 0 are set.
These multiplication coefficients are continuously set by Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time.

In steps 72 to 74, counting of the number of periods Δi of the sampling signal is started. The multiplication coefficients a3 = 1 and ao = a1 = a2 = a4 = 0 are set.
These multiplication coefficients are continuously set by Δi = 500, that is, 500 × 0.0226 ms = 11.3 ms in terms of time.

Therefore, according to the present embodiment, the delayed signal to the initial reflected sound generating means 312 is τ time (1
The signal whose delay time is shifted by (ms) is output, and its cycle is 11.3 ms × 8 = 90.4 ms. The above is a case where the multiplication coefficient is made variable periodically, but as described below, it is not necessary to have periodicity. FIG. 11 is a diagram showing a flowchart for changing the multiplication coefficient of another initial delay modulation means. As shown in the figure, in step 81, the delay modulation control means 315 has a random number generator (not shown),
This random number generator determines which multiplication coefficient should be set to 1 and other multiplication coefficients to be set to 0.

In step 82, the determined multiplication coefficient is set in the multiplier. In step 83,
The counting of the period number Δi of the sampling signal is started. In step 84, the delay data in which the multiplication coefficient is set to 1 is output to the initial reflected sound generation means 312. Continue until Δi = 500, as shown in step 85. The above process is repeated.

In the case of outputting to the reverberation sound means 313, the multiplication coefficients bo, b1, b2, b3 and b4 are similarly given.
The same setting can be made, but the description will be omitted because it is redundant.
Modulating the signal in this way (increasing or decreasing the amount of delay) creates an atmosphere in which the periodicity of the original signal is distorted and the image of the sound spreads, so that the effect of the early reflections and reverberations becomes wider and the reverberation sounds natural. become. Furthermore, in the sound field control apparatus according to the first embodiment, the output is 4 channels or more, and if modulation is applied at the output section, modulation will be applied to each channel, and the number of steps of the algorithm Although this causes an increase, according to this embodiment, modulation is applied at the input unit, and an increase in the number of steps can be suppressed.

FIG. 12 is a diagram showing the configuration of a sound field control device according to the third embodiment of the present invention. The sound field control device shown in this figure is a combination of the first and second embodiments. According to this embodiment, a sound field having a weaker correlation with the direct sound can be formed. Since the sound effect delay time randomly changes compared to the above, it is possible to further lower the correlation between the left and right signals and enhance the feeling of spread.

[0039]

As described above, according to the present invention, since the delay time of the stereo signal is changed with time, the left-right correlation can be weakened, and the stereoscopic effect of the effect sound can be enhanced. Further, since the delay time for generating the initial reflected sound signal and the reverberant sound signal of the sound effect signal is changed with time, the spread feeling of the initial reflected sound and the reverberant sound is enhanced.

[Brief description of drawings]

FIG. 1 is a diagram showing a sound field control device according to an embodiment of the present invention.

FIG. 2 is a diagram showing a configuration of a sound field control device according to the first embodiment of the present invention.

FIG. 3 is a diagram showing storage of sound effect data.

FIG. 4 is a diagram showing a flowchart for forming a storage order of sound effects.

FIG. 5 is a diagram showing a flowchart for explaining modulation of a stereo signal.

FIG. 6 is a diagram showing a flowchart for explaining modulation of another stereo signal.

FIG. 7 is a diagram showing a configuration of a sound effect generating means of a sound field control device according to a second embodiment of the present invention.

FIG. 8 is a diagram illustrating a sound field generated by a sound field control device.

9 is a diagram showing a configuration of an initial delay modulation means of FIG.

FIG. 10 is a diagram showing a flowchart for changing the multiplication coefficient of the initial delay modulation means.

FIG. 11 is a diagram showing a flowchart for changing a multiplication coefficient of another initial delay modulation means.

FIG. 12 is a diagram showing a configuration of a sound field control device according to a third embodiment of the present invention.

FIG. 13 is a diagram showing stereo formation obtained by delaying a sound effect processed in monaural in a conventional sound field control device.

[Explanation of symbols]

 3 ... Digital signal processing device 4 ... External RAM 31 ... Effect sound generation means 32 ... Stereo modulation means 33 ... Stereo modulation control means 311 ... Initial delay modulation means 312 ... Initial reflected sound generation means 313 ... Reverberation sound means 315 ... Delay modulation control means

Claims (3)

[Claims] 1. A sound field control device for generating a sound effect signal such as an initial reflected sound signal and a reverberation signal from a direct sound signal, wherein one of the stereo signals generated by branching and delaying the sound effect signal is generated. A sound field control device characterized by changing a delay time with time. 2. The sound field control device according to claim 1, wherein a delay time for delaying the direct sound signal to generate an initial reflected sound signal and a reverberation sound signal of the sound effect signal is changed with time. 3. A sound field control device for generating a sound effect signal such as an initial reflected sound signal and a reverberation signal from a direct sound signal, wherein one of the stereo signals branched and delayed from the sound effect signal is generated. An initial reflected sound signal of the sound effect signal by changing the delay time with time and delaying the direct sound signal,
A sound field control device that changes a delay time for generating a reverberation sound signal with time.