JPH04135100U - Reverberation sound generation device - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose is to generate a reverberant sound signal according to the correlation of reproduced signals. [Structure] A correlation coefficient calculation unit 11 calculates correlation coefficients between L-side and R-side reproduced signals. The control unit 12 determines whether the value of this correlation coefficient is larger or smaller than a predetermined threshold value, and when the value is larger than the predetermined threshold value, the control unit 12 controls the correlation coefficient so as to emphasize the low frequency component based on the L-R side reproduction signal.
When it is smaller, the coefficients of the digital filter section 13 at the front stage of the reverberation sound generation section 14 are controlled so as to generate a reverberation sound signal based on the L+R side reproduction signal.

Description

[Detailed explanation of the idea]

0001

[Industrial application field]

The present invention relates to a reverberant sound generation device, and in particular, it The present invention relates to a reverberation sound generation device that can obtain acoustic effects.

0002

[Conventional technology]

Traditionally, the method of creating a spacious sound field is to add reverberation electrically. There is a method, but this method generally uses a signal with the opposite channel signal slightly subtracted. Based on this, a reverberant sound signal was created.

0003 Figure 6 shows an in-vehicle device using this conventional method to form a spacious sound field. A sound device is shown. In the same figure, 1R and 1L are instrument panel embedded speakers. 2R, 2L are door built-in speakers, 3R, 3L are rear parcel tray built-in speakers. A speaker, 4 is an acoustic signal source such as a CD player, 5 and 6 are reverberation sound adding circuits, and 7 is an initial stage. Reflected sound adding circuits 8, 9, and 10 are amplifiers, respectively.

0004 FIG. 7 shows an example of the configuration of the reverberation sound adding circuit. In the same figure, 40-43 are husbands. 44 to 50 are adder circuits, and 51 to 63 are coefficient multipliers.

[0005]

[Problem that the idea aims to solve]

However, according to the conventional reverberation sound generation method described above, the low frequency components become monaural. Because they are close to each other, there is a drawback that this low frequency component is attenuated. Therefore, a reverberant sound signal is created by adding the signal of the opposite channel. could also be considered, but this would increase the low frequency components, but at the same time, for example, the vocal When you play a song that includes vocals, etc., the vocals may also be emphasized. Ru. Moreover, in this case, the above-mentioned low-frequency components are generally reproduced from the speakers behind the listener. Because of this, the sound from the rear becomes dominant, and the balance of the sound field is lost. There was a drawback that

[0006] The purpose of this invention is to generate reverberation that corresponds to the correlation between the channels of the audio signal being played. To solve the above-mentioned drawbacks by providing a reverberant sound generating device for generating sound. It is in.

[0007]

[Means to solve the problem]

In order to achieve the above object, the reverberation sound generation device according to the present invention a correlation calculation unit that inputs a signal and calculates a correlation coefficient between the two signals; a reverberant sound generation unit that generates a predetermined reverberant sound signal based on the result of the correlation calculation; , a frequency characteristic response of the reverberant sound signal based on the result of the correlation calculation; a filter section that controls the It is determined whether the value obtained as a result of the correlation calculation exceeds a predetermined threshold, and , the reverberant sound signal emphasizes the low frequency components based on the L-R side playback signal. If the threshold value is not exceeded, a reverberant sound signal is generated based on the L+R side playback signal. a control unit that controls coefficients of the filter unit so as to It is characterized by having the following.

[0008]

[Effect]

The L side and R side reproduced signals are input to the correlation calculation section, and the correlation coefficient of both the above signals is calculated. be done. The reproduced signal is input to the reverberation sound generation section via the filter section. If the correlation coefficient exceeds a predetermined threshold, the control section When a reverberant sound signal is generated that emphasizes the low frequency component and does not exceed the threshold value, controls the filter section to generate a reverberant sound signal based on the L+R side reproduced signal. .

[0009]

【Example】

An embodiment of the present invention shown in the drawings will be described below. FIG. 1 shows an embodiment of a reverberation sound generation device according to the present invention. In the same figure, 11 is Correlation coefficient calculation section, 12 is a control section, 13 is a digital filter section, 14 is a reverberation sound generator 15 and 16 are L side and R side reproduction signal input terminals, 17 and 18 are coefficient multipliers, 19 is an adder, and 20 and 21 are L side and R side reverberant sound signal output terminals. The reverberation sound generation unit 14 is configured, for example, as shown in FIG. 2. 30-33 is Canada 34 and 35 are delay circuits, and 36 to 41 are coefficient multipliers.

0010 In FIG. 1, the L side and R side reproduced signals from input terminals 15 and 16 are processed by a correlation calculation section. 11, and the correlation calculation unit 11 calculates a correlation coefficient between the two signals. Further, both of the above signals are inputted to an adder 19 via coefficient multipliers 17 and 18. A composite signal synthesized by is applied to the digital filter section 13. digital The output signal of the filter section 13 is given to the reverberation sound generation section 14, and the generated reverberation sound signal is outputted. From the power terminals 20 and 21, for example, as shown in FIG. The reverberant sound is sent to the side sub-speakers 22 and 23 and reproduced. Note that 24 and 25 are husbands. The L-side and R-side main speakers placed in front of each other reproduce the L-side and R-side playback signals. is added.

[0011] The correlation coefficient calculated by the correlation calculation section 11 is sent to the control section 12, and the correlation coefficient is The controller 12 determines whether the correlation coefficient exceeds a predetermined threshold. the result , when the threshold value is exceeded, the control section 12 controls the coefficient multipliers 17 and 18 and the adder 19 outputs the L-R side reproduction signal and responds to the frequency characteristics of the filter section 13. Reverberation that emphasizes the low frequency components of the L-R side reproduced signal by controlling the Generate a sound signal. Further, when the correlation coefficient does not exceed the threshold value, the control unit 12 controls the L+R side. The coefficient units 17 and 18 and the filter are configured to generate a reverberant sound signal based on the reproduced signal. The data section 13 is controlled.

0012 Figure 4 shows another embodiment of the present invention, in which the above-mentioned reverberant sound generation algorithm is applied digitally. Realized by digital signal processor DSP and microcomputer CPU .

[0013] FIG. 5(a) is a flowchart showing the operation of the CPU, and FIG. 5(b) is a flowchart showing the operation of the DSP. This is a flowchart. As shown in FIG. 5(a), the CPU Then, the correlation coefficient is calculated from the L side and R side reproduced signals, and the above correlation coefficient is calculated in step ST2. Load the relational coefficient into the DSP, determine the song change in step ST3, and if YES , the process returns to step ST1, but if NO, the process returns to step ST3.

[0014] In the DSP, as shown in FIG. 5(b), in step ST4, the input signal, that is, the The L-R or L+R side reproduced signal is multiplied by the coefficient, and in step ST4, the signal is A reverberation sound signal is generated from the obtained signal in step ST5 by applying filter processing to do.

[0015]

[Effect of the idea]

As explained above, according to the present invention, the correlation can be determined from the L side and R side reproduced signals. Since it is possible to generate reverberant sound according to the Ru.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing an embodiment of a reverberation sound generation device according to the present invention.

FIG. 2 is a block diagram showing an example of the configuration of the reverberation sound generation section of the above embodiment.

FIG. 3 is a schematic diagram showing an example of arrangement of reproduction speakers.

FIG. 4 is a block diagram showing another embodiment of the present invention.

FIG. 5 is a flowchart for explaining the operation of the embodiment of FIG. 4;

FIG. 6 is a block diagram showing an example of a conventional in-vehicle audio device.

FIG. 7 is a block diagram showing an example of a conventional reverberation sound generation circuit.

[Explanation of symbols]

11 Correlation coefficient calculation section 12 Control section 13 Digital filter section 14 Reverberation sound generation section

Claims (1)

[Scope of utility model registration request] 1. A correlation calculation unit that inputs L-side and R-side reproduction signals and calculates a correlation coefficient between the two signals, and a reverberation sound that generates a predetermined reverberation sound signal based on the result of the correlation calculation. a generation unit; a filter unit that controls a frequency characteristic response of the reverberant sound signal based on the result of the correlation calculation; and a filter unit that determines whether or not a value obtained as a result of the correlation calculation exceeds a predetermined threshold. , when the threshold is exceeded, a reverberant sound signal is generated based on the L-R side reproduced signal with its low frequency components emphasized, and when the threshold is not exceeded, the reverberant sound signal is generated based on the L+R side reproduced signal. A reverberation sound generation device, comprising: a control section that controls coefficients of the filter section so as to generate a signal.