JPH0786859A - Acoustic device - Google Patents

Abstract

(57) [Summary] [Purpose] The purpose of this study is to make it possible to express the width of a sound field as a combination of parameters such as reverberation time for a direct sound and the level of reflected sound in a one-dimensional quantity relationship. A digital signal processor 2 for generating a plurality of single delay signals and cyclic delay signals based on digital signals and synthesizing and outputting these three signals.
And adjusting the combination of the three signals in the digital signal processor 2 to create a plurality of sound field patterns, changing the level and delay time of each signal, and causing the digital signal processor 2 to generate a sound field. And a microcomputer 7 for switching the feeling of expansion of the sound field, and the up-down operator 9 gradually increases and decreases the feeling of expansion of the sound field.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an audio device for adjusting a sound field created by using a digital signal processor by an external operation.

[0002]

2. Description of the Related Art FIG. 5 is a block diagram showing a conventional audio apparatus, in which 1 is an analog / digital converter for converting an analog signal as a music source into a digital signal, and 2 is an analog / digital converter 1. 3 is a digital signal processor for processing various audio signals based on the output of the digital signal, 3 is a digital / analog converter for converting a digital signal into an analog signal, and 4 is a volume for adjusting the volume.

Further, 5 is an amplifier as a low frequency amplifier for amplifying the output of the volume 4, 6 is a speaker for audio output, 7 is a microcomputer for controlling the digital signal processor 2, 8 is a display, and 15 is a display. A delay time selection switch, 16 is a signal level selection switch, and 17 is a channel selection switch.

FIG. 6 shows an analog (continuous time) input signal 2
3 shows a timing chart showing the relationship between a and a digital (discrete time) output signal 2b corresponding thereto and the sampling cycle 2c, and here shows the input / output state of the analog / digital converter 1. The digital / analog converter 3 reversely converts the digital signal into an analog signal.

FIG. 7 is a block diagram showing the details of the digital signal processor 2. In FIG.
a is an input signal, 2b is a digital output signal, 21 is an adder, 22 is a digital input signal delay device, 23 is a multiplier which forms a reflected sound generation system together with the delay device 22, 24,
Reference numeral 26 denotes a delay device 22 that forms a reverberation sound generation system together with the adder 25 and the multipliers 27 and 28, and is configured to add a direct sound and a reflected sound in the adder 21 to generate a reverberation sound.

FIG. 8 is a signal flow diagram of the response pattern of FIG. 7, in which the y-axis direction represents amplitude and x
The axial direction represents the delay time, 4a is a direct sound as a digital input signal, 4b is a reflected sound as a digital signal, 4d, 4e and 4f are delay times by delay devices 22, 24 and 26, and 4c1 to 4cx are reverberation sounds. Is.

In the conventional sound field creation, the reverberation time for the direct sound, the magnitude (amplitude) of the reflected sound and the reverberant sound, and the reflected sound for the direct sound are generally used as parameters representing the spread, depth and atmosphere of the sound field. There are the number and the number of reverberant sounds (density).

Next, the operation will be described. First, the power of the audio device is turned on, and then, as an input signal 2a from a radio, a television recorder, a CD player, or the like, as shown in FIG.
When an acoustic source as shown in (a) is input, this is converted into a digital output signal 2b as shown in FIG. 6 (b) by the analog / digital converter 1 and is then supplied to the digital signal processor 2. Is entered.

Therefore, in the digital signal processor 2, the delay time selection switch 15, the signal level selection switch 16 and the channel selection switch 17 are provided.
Based on the calculation and switching control of the sound field pattern by the microcomputer 7 by specifying the sound field element by, the predetermined reflected sound and reverberant sound are generated and output by the product-sum calculation.

The sound field signal output is digital /
After being converted into an analog signal by the analog converter 3, the output is adjusted by the volume 4, the sound quality is adjusted and amplified by the amplifier 5, and output as a sound signal with a sound field effect from the speaker 6. Become.

It should be noted that each of the delay units 22, 24,
26 is constituted by the following operating principle, for example. That is, as shown in FIG. 9, arbitrary data R is stored in the address A of the memory, and an arbitrary calculation program is operated C times to extract the value S from the address B. Where R and S are the same,
During this time, a delay of C × (time for one program cycle) is generated.

In the case of the digital signal processor 2, the address changes from A to A + 1 after one cycle of the program on the hardware. Therefore, if the arbitrary addresses A and B are designated by software. , It is possible to create an arbitrary delay that is an integral multiple of the program period.

The creation of the sound field according to FIG. 7 can be explained with reference to FIG. Now, when the signal of the direct sound 4a is input as the digital input signal 2a, it enters each of the delay devices 22 and 24, and after an arbitrary time, the multiplier 23 respectively.
And output to the adder 25.

Further, the signal of the direct sound 4a is input to the adder 21, but at this time, since the outputs from the delay units 22 and 24 have not been obtained yet, the signal of the direct sound 4a is output as the digital output signal 3b. Only is output as is.

The signal input to the multiplier 23 is multiplied by an arbitrary coefficient (0 to 1) here and output to the adder 21 as a signal of the reflected sound 4b in FIG. Further, the signal input to the adder 25 is added to the output of the multiplier 27, input to the delay device 26, delayed by a predetermined time, and input to the multiplier 27.

Further, the delayed signal is multiplied by an arbitrary coefficient (0 to 1) in the multiplier 27, input to the adder 21, and further output as a digital output signal 2b. This signal corresponds to the reverberation sound 4c1 in FIG. At this time, the output of the multiplier 27 also enters the multiplier 28 at the same time,
This signal is also multiplied by an arbitrary coefficient (0 to 1) and output to the adder 25.

At this time, since the adder 25 has no output from the delay device 24, the output of the multiplier 28 is again provided to the delay device 26.
Is input to the adder 21 and is output again as a digital output signal 2b from the adder 21. This signal corresponds to the reverberation sound 4c2 in FIG. After that, in the same way,
The reverberation sound 4c3, the reverberation sound 4c4, the reverberation sound 4c5, ... Are produced as a cyclic delay signal.

In the above description, the direct sound 4a is one digital pulse input, but in actual music, the direct sound 4a is continuous as shown in FIG. 6, and the direct sound 4a is successively input as a digital input signal in the sampling period. It is input.

When the sound field is created according to the above parameters, the physical quantity such as reverberation time for the direct sound should be determined to be optimum for the target sound field. Further, when reproducing a stereo sound field, at least two left and right channel sound sources are required, and in an audio device for the purpose of creating a sound field, generally four or more channel speakers are arranged. That is, it is necessary to determine the number of parameters obtained by multiplying the physical quantity by the number of reproduction channels.

Further, when it is desired to obtain a desired feeling of expanse with respect to a preset sound field pattern,
In the past, each of the above parameters was varied to find the optimum combination. That is, in FIG. 5, by using the delay time (delay time) table and the gain (signal level) table as shown in FIG. 10, the delay time and the gain are individually selected from the respective tables by the respective selection switches 1i to 1k. It was adjusted by operating.

Although such a method is very cumbersome and it is difficult to make such adjustments during driving, it is possible to carry out any combination of delay time and gain, in particular listening. Depending on the taste of the person, it was possible to reproduce the characteristics of a music hall that does not actually exist.

[0022]

Since the conventional acoustic device is constructed as described above, when the sound field is changed according to the preference of the user, the physical quantities concerning many parameters must be adjusted separately. However, there is a problem that the handling of the sound field selection function is complicated and troublesome.

Further, when the vehicle-mounted audio system is installed in a vehicle, for example, the operation for setting the sound field is only one hand during the operation of the steering wheel, and the number of switches on the operation surface in the layout of the instruments. Due to the lack of a large number of vehicles, there were problems such as deployment in vehicles with various restrictions in terms of operability and safe driving. In addition, as a technique similar to such a conventional audio device, the actual Kaihei 4-558 is used.
There is one disclosed in Japanese Patent No. 25.

The invention of claim 1 has been made to solve the above-mentioned problems, and one-dimensionally determines the width of the sound field by a combination of parameters such as reverberation time for the direct sound and the level of the reflected sound. The purpose of the present invention is to provide an audio device that can be easily operated and selected so as to obtain a desired sound field effect without giving a user meaningless confusion.

It is an object of the present invention to provide an audio device in which the delay time and the amount of change in signal level are matched with the human sense to facilitate grasping the change in the feeling of sound field spread.

It is an object of the invention of claim 3 to obtain an acoustic device in which any person can easily set the sound field using the room size as an index.

It is an object of the invention of claim 4 to obtain an acoustic device capable of creating a sound field richer in atmosphere by using a filter.

An object of the invention of claim 5 is to provide an acoustic device capable of preventing the conventional features from being lost when the problem of complicated and troublesome handling is solved in the invention of claim 1.

[0029]

According to a first aspect of the present invention, there is provided an audio apparatus, wherein a digital signal is used as an original signal and a plurality of single delay signals and cyclic delay signals are generated based on the original signal. Digital that combines and outputs signals
A signal processor and a combination of the original signal, the single delay signal, and the cyclic delay signal in the digital signal processor are adjusted to create a plurality of sound field patterns, and the level of each signal with respect to the sound field pattern. And the delay time to change the digital signal
The processor is equipped with a microcomputer that switches the feeling of sound field expansion, and the up / down operator controls
The sound field spread feeling is gradually increased and gradually decreased.

According to a second aspect of the present invention, there is provided an audio apparatus, which causes a microcomputer to create a plurality of sound field patterns by adjusting a combination of an original signal, a single delay signal and a cyclic delay signal in a digital signal processor, The level of each of the signals is proportionally changed with respect to the sound field pattern, and the delay time is changed isosterically so that the digital signal processor switches the sense of sound field spread. is there.

In the audio device according to the invention of claim 3, the up / down operator can be operated so as to gradually increase or decrease the sense of expanse of the sound field using the room size as an index.

According to a fourth aspect of the present invention, the audio device is configured such that the filter characteristics of the filters connected in the front stage and the rear stage of the digital signal processor are changed according to the room size adjustment.

According to a fifth aspect of the present invention, in addition to the first aspect of the invention, an audio device is provided with a delay time selection switch and a signal level selection switch.

[0034]

According to the sound apparatus of the present invention, the width of the sound field is represented by a combination of parameters such as the reverberation time for the direct sound and the level of the reflected sound in a one-dimensional quantity relationship. This makes it easy to perform operations and selections that give the desired sound field effect without causing unnecessary confusion.

In the audio device according to the second aspect of the present invention, the signal level is expressed logarithmically (equal ratio intervals), and the change amount thereof can be treated linearly, so that the change amount of the delay time and the signal level is sensed by the human sense. To facilitate understanding of changes in the feeling of sound field spread.

According to the third aspect of the present invention, the sound device can easily set the sound field by using the room size as an index.

According to the fourth aspect of the invention, the acoustic device can create a sound field with a richer atmosphere by adding a film characteristic suitable for the room size.

In the audio device according to the fifth aspect of the present invention, the delay time selection switch and the signal level selection switch are independently used or used in combination with the up / down operator to provide a desired sound field which cannot be obtained only by the up / down operator. Make it possible to create.

[0039]

EXAMPLES Example 1. An embodiment of the present invention will be described below with reference to the drawings. In FIG. 1, 1 is an analog / digital converter for converting an analog signal as a music source into a digital signal, and 2 is an original signal based on the digitally converted digital signal, and a plurality of single delay signals and cyclic type signals based on the original signal. It is a digital signal processor that generates a delayed signal, synthesizes these three signals, and outputs them.

Further, 3 is a digital / analog converter for converting the output signal of the digital signal processor 2 into an analog signal, 4 is a volume for adjusting the level of the analog output, and 5 is for adjusting the output of the analog-converted signal. It is an amplifier that outputs to the speaker 6 after

Further, 7 is the digital signal
The combination of the original signal, the single delay signal, and the cyclic delay signal in the processor 2 is adjusted to create a plurality of sound field patterns, and the level and delay time of each signal are changed with respect to the sound field pattern. It is a microcomputer that causes the digital signal processor 2 to switch the feeling of sound field expansion.

Further, 9 is an up-down operator which is operated so as to gradually increase and decrease the feeling of the sound field.
Reference numeral 8 is a display device for displaying a voice output level, a sound field spread and the like.

Next, the operation will be described with reference to the flowchart of FIG. First, adjust the power switch,
Perform initial setting operations such as volume adjustment, sound quality adjustment,
To enter the sound field setting mode, key input is performed (step ST1).

Subsequently, the up / down operator 9 shown in FIG.
Is operated to raise the sound field using the room size as an index, the up-down operator 9 is operated up (step ST2), and conversely, when the sound field is lowered, the up-down operator 9 is operated down (step ST3). When the up operation is performed, the memory address is incremented (step ST
4) If the down operation is performed, the memory address is counted down (step ST5).

Therefore, the microcomputer 7 reads the room size parameter corresponding to each memory address from the memory (step ST6) and transfers the parameter to the digital signal processor 2 (step ST7). Then, if the setting mode is continued (step ST8), the process from step ST2 is executed, and if it is not continued, the process stands by for another process (step ST9).

The room size parameter is, as shown in FIGS. 3A and 3B, data in which the delay time and the reflected sound level are associated with the room size. Table is formed corresponding to memory addresses.

That is, in the present invention, these respective parameters are combined as shown in the tables of FIGS. 3A and 3B, and the respective addresses are designated and stored in the memory of the control microcomputer 7. . Also, this combination is for each preset sound field mode,
The combination of parameters with different feelings of expanse corresponds to the room size.

Therefore, by storing such room sizes in order according to the size of the feeling of expanse and memorizing them, the room size is selected by the up / down operator 9, so that the user's favorite sound field can be obtained. You can easily choose.

Example 2. In the above sound field selection, the delay time of the audio signal is changed at equal intervals, and
The level (gain) of the audio signal is changed at equal intervals.
This makes these delay times and level changes easier to handle, and is more consistent with human hearing,
It becomes easier to understand the changing situation of the sound field.

For example, if the delay time is doubled, it is considered that the distance to the wall is doubled when considering the initial reflected sound. Also, by using the logarithmic expression (equal ratio interval) of the signal level (gain), the amount of change can be treated with a linear value, for example, −
The change from 20 dB to -14 dB is also from -10 dB to -4 d
The change of B can also be considered as a change of +6 dB, and the sound field setting and the operation amount of the sound field setting knob can be easily set.

Example 3. In each of the above embodiments, the room size (sound field pattern), the delay time, the sound reflection,
The case where the magnitude of reverberation and the number of reflections and reverberations are combined is shown. As shown in FIG. 4, a delay is further provided in the stage before the input part of the input signal 2a and the stage after the output part of the digital output signal 2b. To create a more diverse and rich sound field by arranging the multiplier 10, the multiplier 11 and the filters 12 and 13 and combining the delay time and the filter coefficient of the signal input to and output from the digital signal processor 2. You can also

In this case, reference numeral 20 is an interlocking control signal output from the digital signal processor 2 in response to the selection switching of the room size. By switching the interlocking control signal 20, the characteristics of the filters 12 and 13 are changed in association with the selection switching of the room size, and a more comfortable sound field effect can be produced.

Example 4. In the music apparatus of the first embodiment described above, the operation becomes easy, but it becomes impossible to select the characteristics other than the characteristics set in the predetermined table. The taste of music varies from person to person, and some people may not be satisfied with the above table in which settings imitating a music hall in a range considered to actually exist are input.

On the other hand, although it is easy to input a large number of combinations in the table, such an arrangement increases the difficulty in selecting by the operator, resulting in a result contrary to the intended purpose. Therefore, in order to solve such a contradiction, the delay time selection switch 15 and the signal level selection switch 16 of FIG. 5 may be further used in combination with the apparatus of FIG. 1 of the first embodiment.

Although not shown in the figure, a switch for selecting whether to operate using the up / down operating element 9 or the conventional selection switches 15 and 16 may be additionally provided. Good.

Further, the up / down operator 9 and the above-mentioned selection switches 15 and 16 are configured so as to operate in parallel (at the same time), and by operating these selection switches 15 and 16, the operator can select a desired sound field. You may make it shift the characteristic change range by the up-down operator 9 toward the characteristic with which a feeling is obtained. If the shape of the selection switches in such a case is such that they are operated by using a driver, for example, no problem will occur with respect to the above-mentioned small space around the driver's seat.

[0057]

As described above, according to the invention of claim 1, a digital signal is used as an original signal, and a plurality of single delay signals and cyclic delay signals are generated based on the original signal.
A digital signal processor that synthesizes and outputs these three signals and a combination of the original signal, the single delay signal, and the cyclic delay signal in the digital signal processor are adjusted to create a plurality of sound field patterns. , A microcomputer for changing the level and delay time of each of the signals with respect to the sound field pattern to cause the digital signal processor to switch the sense of spread of the sound field, and the sound field by the up-down operator. Since it is configured to gradually increase and decrease the feeling of expanse, the width of the sound field is expressed by a combination of parameters such as reverberation time for the direct sound and the level of the reflected sound in a one-dimensional quantity relationship. It is possible to obtain a desired sound field effect that can be easily operated and selected without causing unnecessary confusion. There is a result.

According to the invention of claim 2, the microcomputer is caused to adjust the combination of the original signal, the single delay signal and the cyclic delay signal in the digital signal processor to create a plurality of sound field patterns, Since the level of each of the above signals is proportionally changed with respect to the field pattern and the delay time is changed isochronously, the digital signal processor is configured to switch the sense of sound field spread. There is an effect that a change in time and signal level can be matched with a human sense to facilitate grasping a change in the sense of sound field spread.

According to the third aspect of the present invention, the up / down operator can be operated so as to gradually increase or decrease the sense of expanse of the sound field using the room size as an index, so that the room size is used as an index. There is an effect that a person can easily set the sound field.

According to the invention of claim 4, the filter characteristics of the filters connected to the front and rear stages of the digital signal processor are changed according to the room size adjustment. It has the effect of creating a sound field with a rich atmosphere.

According to the fifth aspect of the invention, the up-down operator is operated independently or in combination,
Since the delay time selection switch and the signal level selection switch that arbitrarily change the delay time and the level of each signal with respect to the sound field pattern are provided, the sense of spread of the sound field is gradually increased by the up / down operator. In addition to the effect of the invention of claim 1 that can be gradually reduced, a unique characteristic according to operator preference or a characteristic that is not within the adjustment range of the up / down operator can be set. There is an effect that it is possible to obtain a sound device that the user has.

[Brief description of drawings]

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

FIG. 2 is a flowchart showing a sound field signal output processing procedure according to the present invention.

3 is a table showing a table of room size parameters stored in a memory in the microcomputer shown in FIG.

FIG. 4 is a block diagram showing a main part of an audio device according to an embodiment of the invention of claim 4;

FIG. 5 is a block diagram showing a conventional acoustic device.

6 is a waveform diagram showing an analog input signal and a digital output signal of the analog / digital converter in FIG.

7 is a block diagram showing details of the digital signal processor in FIG.

FIG. 8 is a timing chart showing signals in each part of the block of FIG.

9 is an explanatory diagram showing the operation of the delay device in FIG. 7. FIG.

10 is a table diagram showing a delay time table and a gain table stored in a memory in the microcomputer shown in FIG.

[Explanation of symbols]

 1 analog / digital converter 2 digital signal processor 3 digital / analog converter 5 amplifier 6 speaker 7 microcomputer 9 up / down operator 12, 13 filter 15 delay time selection switch 16 signal level selection switch

Claims (5)

[Claims] 1. An analog / digital converter for converting an analog signal as a music source into a digital signal, and a plurality of single delay signals and cyclic delay signals based on the original signal which is the digital converted digital signal. A digital signal processor for generating and synthesizing and outputting these three signals, a digital / analog converter for analog-converting the output signal of the digital signal processor, and an output adjustment of the analog-converted signal. After that, the combination of the amplifier output to the speaker and the combination of the original signal, the single delay signal and the cyclic delay signal in the digital signal processor is adjusted to create a plurality of sound field patterns. By changing the level and delay time of each of the above signals,
An audio device comprising: a microcomputer that causes the digital signal processor to switch a feeling of sound field expansion; and an up-down operator that is operated to gradually increase and decrease the feeling of sound field expansion. 2. An analog / digital converter for digitally converting an analog signal as a music source, and a plurality of single delay signals and cyclic delay signals based on the original signal, which is the digitally converted digital signal. A digital signal processor for generating and synthesizing and outputting these three signals, a digital / analog converter for analog-converting the output signal of the digital signal processor, and an output adjustment of the analog-converted signal. After that, the combination of the amplifier output to the speaker and the combination of the original signal, the single delay signal and the cyclic delay signal in the digital signal processor is adjusted to create a plurality of sound field patterns. The level of each signal is changed proportionally, and the delay time is changed proportionally. An audio device comprising a microcomputer for causing the digital signal processor to switch the sound field expanse, and an up-down operator operated to gradually increase and decrease the sound field expanse. 3. An analog / digital converter for digitally converting an analog signal as a music source, and a plurality of single delay signals and cyclic delay signals based on the original signal, which is the digitally converted digital signal. A digital signal processor for generating and synthesizing and outputting these three signals, a digital / analog converter for analog-converting the output signal of the digital signal processor, and an output adjustment of the analog-converted signal. After that, the combination of the amplifier output to the speaker and the combination of the original signal, the single delay signal and the cyclic delay signal in the digital signal processor is adjusted to create a plurality of sound field patterns. By changing the level and delay time of each of the above signals,
An audio device provided with a microcomputer for causing the digital signal processor to switch the feeling of sound field expansion and an up-down operator operated to gradually increase and decrease the feeling of sound field expansion with room size as an index. . 4. An analog / digital converter for digitally converting an analog signal as a music source, and a plurality of single delay signals and cyclic delay signals based on the original signal, which is the digitally converted digital signal. A digital signal processor for generating and synthesizing and outputting these three signals, a digital / analog converter for analog-converting the output signal of the digital signal processor, and an output adjustment of the analog-converted signal. After that, the combination of the amplifier output to the speaker and the combination of the original signal, the single delay signal and the cyclic delay signal in the digital signal processor is adjusted to create a plurality of sound field patterns. By changing the level and delay time of each of the above signals,
A microcomputer for causing the digital signal processor to switch the sound field expanse, an up / down operator operated to gradually increase and decrease the sound field expanse with room size as an index, and the digital signal・ Connected to the front stage of the processor,
An audio device comprising: a filter whose filter characteristics are changed according to the room size adjustment. 5. An analog / digital converter for digitally converting an analog signal as a music source, and a plurality of single delay signals and cyclic delay signals based on the original signal, which is the digitally converted digital signal. A digital signal processor for generating and synthesizing and outputting these three signals, a digital / analog converter for analog-converting the output signal of the digital signal processor, and an output adjustment of the analog-converted signal. After that, the combination of the amplifier output to the speaker and the combination of the original signal, the single delay signal and the cyclic delay signal in the digital signal processor is adjusted to create a plurality of sound field patterns. By changing the level and delay time of each of the above signals,
A microcomputer that causes the digital signal processor to switch the sound field expansion feeling, an up-down operator that is operated to gradually increase and decrease the sound field expansion feeling, and the up-down operator independently. Or a combination thereof, which is arbitrarily operated, and includes a delay time selection switch and a signal level selection switch for arbitrarily changing the delay time and the level of each signal with respect to the sound field pattern.