JPH06232662A - Sound volume controller - Google Patents

Abstract

PURPOSE:To realize an ideal loudness characteristic. CONSTITUTION:The controller is provided with a 1st attenuator 3a and a 2nd attenuator 3b dividing a signal from a sound signal source 1 into a desired frequency band by a high pass filter 4 and a low pass filter 7 to control the sound volume of each frequency band independently, an attenuation control means 12 receives a position of a sound volume adjustment knob 10 to vary the attenuation of the 1st and 2nd attenuators 3a, 3b depending on the position of a sound volume knob. Since a low frequency sound or a high frequency sound is optionally emphasized depending on the position of the sound volume, the ideal loudness characteristic is realized.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a volume control device, and more particularly to a loudness function.

[0002]

2. Description of the Related Art FIG. 13 is a block diagram showing an embodiment of a conventional volume control device with a loudness function. 1 is an audio signal source, 2 is an electronic volume, an attenuator operated by an electric signal, 4 is a high-pass filter, 5 is an amplifier, 6 is a speaker, 7 is a low-pass filter, 8 is an amplifier, 9 is a speaker, 10 is The volume adjusting knob is a volume instructing means for instructing the volume. 12 is a microcomputer, 13
Is a boost circuit for loudness, which is connected to the electronic volume 2.

The audio signal from the signal source 1 is an electronic volume 2
Then, the sound is attenuated to a desired level, passes through the high-pass filter 4 and the amplifier 5, and the high-pitched sound is reproduced from the speaker 6, and the signal passed through the low-pass filter 7 passes through the amplifier 8 and the low-pitched sound is reproduced from the speaker 9. The attenuation amount of the electronic volume 2 is determined by the microcomputer 12 by taking the position of the volume adjusting knob 10.

FIG. 14 is an internal circuit diagram of the electronic volume 2. The signal is input to the ladder resistor 2a, and the analog switch 2b is turned on so that the desired attenuation amount is obtained. Normally Figure 1
The ladder resistor 2a has a two-stage structure as shown in FIG.
It is changed in dB steps, switched and output by the analog switch 2b, the signal is input to the ladder resistor 2c which can be switched by 2 dB steps, and switched and output by the analog switch 2d. Analog switch 2
The microcomputer 12 turns on / off b and 2d.
The control circuit 2e controls with the data from. Ladder resistance 2
A boost circuit 13 can be connected to the intermediate tap of a so that a loudness function that can emphasize low tones can be realized when the volume position is low.

[0005]

In such a conventional volume control device, the ladder resistance 2a has a large amount of change in one step, and therefore can be set only in several ways. 2a is 10 dB
Assuming that it changes in steps, 0 to −10 dB, −
Since only 3 ways of 10 dB to -20 dB and -20 dB or less can be set, the change is too large at the time of switching, and there is a feeling of strangeness. Further, since the boost circuit is composed of a primary filter, there is a problem that a characteristic of 6 dB / oct or more cannot be obtained.

The present invention has been made to solve the above problems, and an object thereof is to realize an ideal loudness characteristic.

[0007]

A volume control device according to the present invention comprises a filter for dividing an audio signal into a plurality of frequency bands, an attenuator for attenuating the audio signal for each of the divided frequency bands, It is provided with a volume instructing means for instructing to make a desired volume and an attenuation amount controlling means for individually changing the attenuation amount of each attenuator in response to this instruction.

The volume control device according to the present invention is
Attenuation amount control means is provided for controlling the amount of change of one attenuator to be smaller than the amount of change of another attenuator in response to a volume instruction.

The volume control device according to the present invention is
In the specified volume range of the volume indicating means, the change amounts of one attenuator and the other attenuator are the same, and in the other specified volume range, the change amount of one attenuator is the same as that of the other attenuator. The amount of change is smaller than that of the other attenuator, and the amount of change of one attenuator is controlled to be larger than the amount of change of the other attenuators in the other volume indication ranges.

The volume control device according to the present invention is
From the maximum value to the predetermined volume value of the volume instruction value of the volume instruction means, the attenuation amount control means for controlling the attenuation amounts of the respective attenuators to be substantially equal is provided.

The volume control device according to the present invention is
A filter for dividing the audio signal into a plurality of frequency bands,
An attenuator for attenuating the audio signal for each of the divided frequency bands, a volume instructing means for instructing to set a desired volume, and an attenuation amount of each of the attenuators are individually changed according to the instruction. The attenuation amount control means, the storage means for storing a plurality of patterns having different change characteristics of the volume instruction value and the attenuation amount of the volume instruction means, and a desired pattern of the patterns is selected and input to the attenuation amount control means. And a switching means for switching.

[0012]

When the volume control device of the present invention is instructed to make a desired volume, the attenuation amount of each attenuator divided into a plurality of frequency bands is individually changed according to the instruction.

Further, the volume control apparatus of the present invention controls the variation of one attenuator to be smaller than the variation of another attenuator in response to the volume instruction.

Further, in the volume control device of the present invention, the change amount of one attenuator and the other attenuator are the same in the specified range of the specified volume of the volume indicating means, and in the specified range of the other specified volume. The change amount of one attenuator is smaller than the change amount of another attenuator, and the change amount of one attenuator is controlled to be larger than the change amount of another attenuator in other volume ranges.

Further, in the volume control device of the present invention, when the volume instruction value of the volume instruction means is from the maximum value to the predetermined volume value,
The amount of attenuation of each attenuator is controlled to be approximately equal.

Further, the volume control device of the present invention selects a desired pattern among the patterns of the change characteristics of the volume instruction value and the attenuation amount of the volume instruction means, and it is desirable that the volume instruction is given from the voice instruction means. The attenuation amount of each attenuator divided into a plurality of frequency bands by the pattern is individually changed.

[0017]

EXAMPLES Example 1. FIG. 1 is a block diagram showing an embodiment of a volume control device of the present invention. The signal from the signal source 1 is input to the first attenuator 3a and the second attenuator 3b.
The signal attenuated by the first attenuator 3a passes through the high-pass filter 4, is amplified by the amplifier 5, and the mid-high range sound is reproduced from the speaker 6.

The output of the second attenuator 3b is input to the low-pass filter 7, passes through the amplifier 8, and the low-pitched sound is reproduced by the speaker 9. First attenuator 3a and second attenuator 3
The attenuation amount of b is determined by the attenuation amount control means 11 which takes in the position of the volume control knob 10, and is independently controlled.

Assuming that the first attenuator 3a and the second attenuator 3 are
It is assumed that b is the same and that the attenuation amount can be changed in 1 dB steps. At the position where the volume adjusting knob is at the maximum, the attenuation amounts of both the first attenuator 3a and the second attenuator 3b are zero, but the first attenuator 3 is lowered each time the volume adjusting knob is lowered.
The attenuator control means controls so that a is increased by 2 dB and the second attenuator 3b is increased by 1 dB. First attenuator 3
Since a controls the volume of the mid-high range, the mid-high range is 2 dB.
However, the low-pitched sound whose volume is controlled by the second attenuator 3b changes only by 1 dB, and thus has the changing characteristic as shown in FIG. 4, and the lower-pitched sound volume is emphasized. In addition, since it changes finely, there is no discomfort when switching.

Such an attenuation amount control means can be easily realized by a program of a microcomputer. FIG. 2 is a block diagram when a microcomputer is used as the attenuation amount control means 11. Reference numeral 12 in the drawing is a microcomputer, which has a CPU 14, a memory 15, an input circuit 16, and an output circuit 17. An A / D converter 18 converts the voltage of the volume adjusting knob 10 into a digital signal.

Next, the operation will be described with reference to the flowchart of FIG. First, in the volume knob position input step 30, the volume position is input. In step 31, the volume position stored in the microcomputer 12 is compared with the volume position input in step 30, and if the volume position has changed, the process proceeds to the next step and the attenuation amount is changed. If they are the same, the process returns to step 30 and the operation is repeated. In order to change the attenuation amount, when the process proceeds to step 32, the process is divided depending on whether the volume is up or down.

To increase the volume, steps 33 and 34
To 1 dB for the second attenuator 3b and the first attenuator 3a.
Is changed so that the sound volume is up by 2 dB, and the data is output to each attenuator. When the volume is down, the attenuation amount is changed in steps 35 and 36 so that the volume is down, and the data is output to each attenuator. When the series of processes is completed, the process returns to step 30 and the same process is repeated. In this way, the first attenuator 3a can be changed in 2 dB steps and the second attenuator 3b can be changed in 1 dB steps.

Example 2. Further, as shown in the flowchart of FIG. 5, when changing the attenuation amount, steps 50 and 51 are performed.
a, 51b and steps 52, 53a and 53b, the second attenuator 3b changes in 1 dB steps within the range of 61 from the volume MAX to the predetermined volume position as shown in the change characteristic of FIG. In the range of 1, the change can be made in the same 2 dB step as the first attenuator 3a, and the bass is not emphasized too much and the sound quality balance is not disturbed.

Example 3. Further, the processing for determining the attenuation amount of the second attenuator 3b as in the flowchart of FIG. 7 is performed by steps 70a, 70b, 71a to 71c, 72a, 72.
b, 73a to 73c, it is possible to change the range 81 in the range 81 of FIG. 8 in 1 dB steps, the range 82 in 2 dB steps, and the range 83 in 4 dB steps. By adopting the change characteristic as shown in FIG. 8, it is possible to prevent the residual sound when the volume is minimized.

Example 4. Further, steps 90a to 90c, 91a to 91c, and step 9 in the flowchart of FIG.
If the processes 2a to 92c and 93a to 93c are performed, as shown in the change characteristic diagram of FIG. 10, in the range 101 from the volume MAX to the predetermined position, the first attenuator 3a and the second attenuator 3a are provided.
Attenuator 3b changes similarly, up to the range of 102 the second attenuator 3b changes in 1 dB steps, and in the range of 103 the same 2 dB steps as the first attenuator 3a
The range of 04 can be changed in 4 dB steps.

In this way, the volume position at which the loudness begins to be effective can be arbitrarily determined, and the loudness effect can be restricted so as not to be too effective, so that the loudness characteristic can be set in accordance with the characteristics of the speaker or the amplifier.

Example 5. Further, as shown in the block diagram of the attenuation amount control means of FIG. 11, the first memory 15a, the second memory 15b, and the third memory 15c, which store different control patterns as the storage means, and the control pattern of which memory If the switching means 19 for switching whether to control is provided, the loudness characteristics can be switched according to the characteristics of the speaker and the amplifier.

FIG. 12 is a flow chart showing the operation of the fifth embodiment. The operation will be described with reference to FIG. The state of the switching means 19 is input to the input circuit 16 and stored in the microcomputer 12. When the position of the volume knob changes, the process proceeds to step 120, where the process branches to steps 121 to 123 depending on the state of the switching means 19 stored in the microcomputer 12. Each calculates the attenuation amount of each attenuator according to the control pattern stored in the memory, and outputs a control signal. Thus, the loudness characteristic can be changed only by changing the state of the switching means, which is versatile.

Example 6. In the above embodiment, the microcomputer is used as the attenuation control means, but the characteristic of the resistor of the variable resistor is changed, the DC voltage with respect to the position of the volume knob is set to a different value, and each attenuator is controlled by the DC voltage. You may

Example 7. In the above embodiment, the high pass filter 4 and the low pass filter 7 are connected after the first attenuator 3a and the second attenuator 3b as shown in FIG.
High-pass filter 4 and low-pass filter 7 for signal source 1
May be connected, and then the first attenuator 3a and the second attenuator 3b may be respectively connected.

Example 8. Further, in the above-described embodiment, the first attenuator 3a is used for middle and high frequencies, and the second attenuator 3b is used for low frequencies. However, in the case of a three-way speaker of high tone, medium tone and low tone, high tone is generated. For high frequencies, a high-pass filter and a first attenuator are connected in series, for medium frequencies, a band-pass filter (cutting high and low frequencies) and a second attenuator are connected in series,
For low-pitched sound, a low-pass filter and a third attenuator are connected in series, and the first, second, and third attenuators are controlled by the attenuation amount control means to change the volume change characteristic. May be. In this case, a characteristic of a finer volume change can be obtained.

For a speaker system of 3 ways or more such as 4 ways, or a multiway system having other surround channels, an attenuator is used at a necessary place and controlled by an attenuation amount control means. Good.

Example 9. Also in a 3-way speaker system, a high-pass filter and a band-pass filter are connected after the first attenuator to drive a high-frequency speaker and a mid-frequency speaker, respectively, and a second attenuator is used. A low pass filter may be connected to drive a bass speaker. That is, two attenuators are associated with three speakers and controlled by the attenuation amount control means. It should be noted that the first attenuator may be used for high frequencies and the second attenuator may be used for medium and low frequencies. In this embodiment, a three-way speaker has been described, but it can be applied to four or more speakers such as a four-way speaker.

[0034]

As described above, according to the present invention, since the sound volume of each of the frequency bands divided into a plurality of parts is individually controlled, it is possible to finely control the grain of wood and to feel a sense of discomfort when the sound volume changes. There is an effect that it can be eliminated and a sufficient loudness effect can be obtained. In addition, since the loudness characteristic can be set according to the characteristics of the speaker and the amplifier, there is an effect that an ideal loudness characteristic can be realized.

[Brief description of drawings]

FIG. 1 is a block diagram of a volume control device according to a first embodiment of the present invention.

FIG. 2 is a block diagram of attenuation amount control means according to the first embodiment of the present invention.

FIG. 3 is a flowchart showing the operation of the first embodiment of the present invention.

FIG. 4 is a volume change characteristic diagram of the first embodiment of the present invention.

FIG. 5 is a flowchart showing the operation of the second embodiment of the present invention.

FIG. 6 is a volume change characteristic diagram of the second embodiment of the present invention.

FIG. 7 is a flowchart showing the operation of the third embodiment of the present invention.

FIG. 8 is a volume change characteristic diagram of the third embodiment of the present invention.

FIG. 9 is a flowchart showing the operation of the fourth embodiment of the present invention.

FIG. 10 is a sound volume change characteristic diagram of the fourth embodiment of the present invention.

FIG. 11 is a block diagram of an attenuation amount control means according to a fifth embodiment of the present invention.

FIG. 12 is a flowchart showing the operation of the fifth embodiment of the present invention.

FIG. 13 is a schematic configuration diagram of a conventional volume control device.

FIG. 14 is an internal circuit diagram of an electronic volume 2 of a conventional volume control device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 signal source 2 electronic volume 3a 1st attenuator 3b 2nd attenuator 4 high-pass filter 5 amplifier 6 speaker 7 low-pass filter 8 amplifier 9 speaker 10 volume control knob (volume indicating means) 11 attenuation control means 12 microcomputer 13 Boost circuit 14 CPU 15 Memory (storage means) 15a, 15b, 15c Memory (storage means) 16 Input circuit 17 Output circuit 18 A / D converter 19 Switching means

Claims (5)

[Claims] 1. A filter for dividing an audio signal into a plurality of frequency bands, an attenuator for attenuating the audio signal for each of the divided frequency bands, and a sound volume indicating means for instructing a desired sound volume. A sound volume control device comprising attenuation amount control means for individually changing the attenuation amount of each of the attenuators according to this instruction. 2. When the volume instructing means gives an instruction to change the volume, the attenuation amount control means changes the amount of change of one attenuator to the amount of change of the other attenuator in accordance with the instruction. A volume control device characterized by controlling so as to be smaller. 3. The volume control means according to claim 1, wherein the attenuation amount control means sets the change amounts of one attenuator and another attenuator to be the same in the specified volume range of the volume instructing means, and another specific volume. In the indicated range, the change amount of the one attenuator is smaller than the change amount of the other attenuator, and in the indicated range of other volume, the change amount of the one attenuator is the change amount of the other attenuator. A volume control device that is controlled to increase the volume. 4. The attenuation amount control means according to claim 1, wherein the attenuation amount control means controls the attenuation amounts of the respective attenuators to be substantially equal from the maximum value to the predetermined volume value of the volume instruction value of the volume instruction means. Volume control device characterized by. 5. A filter for dividing an audio signal into a plurality of frequency bands, an attenuator for attenuating the audio signal for each of the divided frequency bands, and a volume instructing means for instructing a desired volume. An attenuation amount control means for individually changing the attenuation amount of each attenuator according to this instruction, and a storage means for storing a plurality of patterns having different change characteristics of the volume instruction value and the attenuation amount of the volume instruction means. And a switching means for selecting a desired one of the patterns and inputting it to the attenuation amount control means. The attenuation amount control means receives the volume instruction from the voice instructing means, and each of the above-mentioned desired patterns is selected. A voice control device characterized in that it controls an attenuator.