JP3285151B2 - Volume control device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[Table of Contents] The present invention will be described in the following order. BACKGROUND OF THE INVENTION Problems to be Solved by the Invention Means for Solving the Problems (FIG. 1) Function (FIGS. 2 and 3) Example (FIGS. 1 to 3) Effects of the Invention

[0002]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a volume control device, and is suitably applied to, for example, a car audio device.

[0003]

2. Description of the Related Art Conventionally, there is an audio device mounted on a vehicle which can selectively reproduce a plurality of compact disks.

That is, in this type of audio device, a magazine containing a plurality of compact disks is inserted into a compact disk player provided in a trunk room, for example. As a result, in the audio apparatus, the operator can remotely operate the compact disk player by operating the operation device arranged on the dashboard, and can selectively reproduce a desired compact disk.

[0005] In this type of audio device, the volume and sound quality of an audio signal to be reproduced can be adjusted according to the driver's preference by operating an operator. Here, the playback volume level of the audio device is, for example, a maximum output of a sound range (hereinafter referred to as dynamic range) in which an audio signal can be reproduced without distortion.
If [dB] is used, it can be expressed as an attenuation x in the negative direction from 0 [dB].

The sound quality of the reproduced sound can be adjusted as desired by a so-called tone controller or equalizer. Here, the tone controller adjusts the sound quality by increasing or decreasing the volume of the low frequency range (bass) and high frequency range (treble) from the flat position, for example, centering on the middle frequency range, and the equalizer increases or decreases only the volume of the specific frequency. By doing so, the sound quality is adjusted.

Here, in this type of audio device, the amplification amount of the sound volume (hereinafter referred to as a boost amount) at the time of sound quality adjustment is increased by a predetermined amount to about +10 to +14 [dB] (+10 [dB]).
B) It is set so that it can be performed. By adjusting the volume and the sound quality, the driver can enjoy the reproduced sound of the desired volume and sound quality.

[0008]

However, as shown in FIG. 3, the boost amount y of a certain frequency band specified by the user is used.
If (<+ B) is larger than the attenuation x of the currently reproduced sound, the dynamic range may be exceeded and the output audio signal may be distorted. For this reason, the dynamic range of the volume that can be adjusted at the volume terminal is such that even if the boost amount y is adjusted to the maximum boost amount (+ B), the maximum output (0 [dB]) is set so that the audio signal volume is within the dynamic range. ]), A margin is provided for the maximum boost amount (+ B).

As a result, there is a problem that the dynamic range of the sound volume which can be adjusted by the volume terminal is narrowed, and a signal-to-noise ratio (hereinafter referred to as S / N) is deteriorated. Further, when only an audio signal in a specific frequency band is amplified to a maximum output (0 [dB]) or more, there is a problem that resonance occurs in the power supply circuit.

The present invention has been made in consideration of the above points, and can increase a dynamic range of a sound volume which can be adjusted by a sound volume adjusting circuit, and can obtain an audio signal having a high S / N. It is intended to propose a device.

[0011]

According to the present invention, in order to solve the above-described problems, a sound volume adjusting means for adjusting a sound volume level of an input audio signal, and a predetermined output audio signal output from the audio volume adjusting means. A sound quality setting means 3 for amplifying or reducing the sound volume level of the frequency band by a predetermined amount to adjust the sound quality of the output audio signal S4, and an attenuation amount x for the maximum output level 0 [dB] of the volume level of the output audio signal S4. Control means 4 for detecting and detecting a volume level amplification correction amount y of the specified output audio signal S4 and setting the increase / decrease y or x of the output audio signal S4 in accordance with the attenuation x.
If the designated volume level amplification correction amount y does not exceed the attenuation amount x, the volume level is amplified and output by the designated input amplification amount y, and the specified volume level amplification correction amount y becomes the attenuation amount. If it exceeds x, the volume level is amplified and output by the amount of attenuation x.

[0012]

In the case where the volume level amplification correction amount y of the specified output audio signal S4 is smaller than the attenuation x for the maximum output level 0 [dB] of the output audio signal S4 currently output,
The control means 4 controls the sound signal S output from the volume control means 2
4 is amplified by the amplification correction amount y and output from the sound quality adjusting means 3, and the specified volume level amplification correction amount y of the output audio signal S4 is the maximum output level 0 [dB] of the currently output audio signal S4. When the sound level is larger than the attenuation amount x, the control means 4 amplifies the sound signal volume level by the attenuation amount x instead of the amplification correction amount y and outputs the amplified sound signal from the sound quality adjustment means 3 so that the sound quality level is adjusted. The adjustment range can be increased or decreased in the range of the maximum output level 0 [dB], and the volume level can be adjusted in a much wider range than in the past.

[0013]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

In FIG. 1, reference numeral 1 denotes an audio device as a whole, which has a volume control circuit 2 and a sound quality control circuit 3 so as to adjust the volume and sound quality of audio signals supplied from various playback devices and output the adjusted signals. Has been made. For example, the audio device 1 includes a reproduced audio signal S1 reproduced from a compact disc player mounted on a car.
Is supplied to the volume control circuit 2.

The volume control circuit 2 controls the volume level (-) from a noise level to a maximum output of 0 [dB] in predetermined steps based on a volume control signal S2 input from the control circuit 4.
x) can be increased or decreased. Sound quality adjustment circuit 3
Increases or decreases the volume level (-x) of the audio signal S1 in the predetermined frequency band based on the sound quality control signal S3 input from the control circuit 4.

That is, the sound quality adjusting circuit 3 increases or decreases the sound volume of the audio signal S1 by the boost amount y in predetermined steps, based on the current sound volume level (-x) (ie, the attenuation amount x), and sends it to the subsequent amplification circuit 5. Output. The amplification circuit 5
The audio signal S4 is amplified so that the speaker 6 operates, and is output to the speaker 6.

Here, the key operation section 7 outputs a volume increase / decrease signal S5 to the control circuit 4 in response to the operation of the volume adjuster 7A or the tone quality adjuster 7B. Control circuit 4
Detects the amount of attenuation x and the amount of boost y from the maximum output 0 [dB] of the audio signal S1 currently being reproduced, and outputs a volume control signal S2 or a sound quality control signal S3 according to the volume increase / decrease signal S5. Has been made.

At this time, the control circuit 4 outputs the audio signal S
A boost amount y in a predetermined frequency band is set depending on whether or not the attenuation amount x from the maximum output 0 [dB] representing the volume of 1 is larger than the maximum boost amount B which is increased or decreased when adjusting the sound quality ( (Fig. 2). That is, the control circuit 4 starts the boost amount setting process from step SP1, as shown in FIG.
In step SP2, the amount of attenuation x of the audio signal S1 and the current amount of boost y are detected.

When the control circuit 4 proceeds to the next step SP3, it waits for the volume control 7A or the tone control 7B to be increased or decreased. The control circuit 4 proceeds to the next step SP4
In, the volume or sound quality adjuster 7A or 7B is operated by the volume increase / decrease signal S5, and an instruction to increase the attenuation x (that is, a decrease in the volume level) is issued or a decrease in the attenuation x (that is, an increase in the volume level) is performed. Detect if it is instructed.

Similarly, the control circuit 4 indicates that the boost amount y for adjusting the sound quality is instructed to increase (that is, the volume level of the predetermined frequency band is increased) or is decreased (that is, the volume level of the predetermined frequency band is decreased). Detect if it is instructed. Here, when detecting that the boost amount y is reduced, the control circuit 4 proceeds to step SP5 and lowers the boost amount y by one step. After that, the control circuit 4
Returns to step SP3, and repeats the above-described operation until the predetermined boost amount y is reduced.

At this time, the control circuit 4 increases or decreases the attenuation x by one step within the dynamic range depending on whether the attenuation x increases or decreases. In this case, the boost amount y is the most boost amount y with respect to the volume attenuation x.
Is not smaller than a value when the value is lowered (hereinafter, referred to as a minimum boost amount (-B)).

On the other hand, upon detecting that the boost amount y is to be increased, the control circuit 4 proceeds to step SP6 to determine whether the boost amount y specified by the user is smaller than the current attenuation amount x. Detect whether or not. If an affirmative result is obtained here (this means that the boost amount y specified by the user is smaller than the attenuation amount x of the audio signal S1), the control circuit 4 proceeds to the next step S.
The process proceeds to P7, where the boost amount y is increased by one step.

After that, the control circuit 4 moves to step SP3 and repeats the adjustment of the volume or the sound quality. On the other hand, if a negative result is obtained (this means that the boost amount y specified by the user is equal to or greater than the attenuation amount x), the control circuit 4 proceeds to step SP8.

Here, if the volume of the audio signal S1 in the predetermined frequency band is increased by the boost amount y specified by the user, the control circuit 4 exceeds 0 [dB] and exceeds the dynamic range of the reproduced signal. , The boost amount y is held at the maximum possible boost amount B1 (= x). After this, the control circuit 4 moves to step SP3 and repeats the adjustment of the volume or sound quality.

In the above configuration, the control circuit 4 detects the current volume level, that is, the attenuation amount x and the current boost amount y from the key operation unit 7. Here, the volume level of the reproduced audio signal S1 with respect to the maximum output level (0 [dB]) is (-x1), and the attenuation x1 at this time is larger than the maximum value B of the boost amount that can be adjusted by the sound quality adjustment circuit 3. If it is larger, the control circuit 4 increases or decreases the volume of the predetermined frequency band by the boost amount y input from the key operation unit 7 by the user (FIG. 3).

That is, the control circuit 4 includes the steps SP1 to SP1.
If it is detected in step SP4 that the user has operated the key so as to decrease the boost amount y for the predetermined frequency band as being too large, the process proceeds to step SP5. Here, the control circuit 4 outputs the volume control signal S2 to the volume adjustment circuit 2, and holds or increases or decreases the volume level to the attenuation amount x specified by the user.

Further, the control circuit 4 outputs the sound quality adjustment signal S3 to the sound quality adjustment circuit 3, and reduces the boost amount y from the current value by a predetermined number of steps. On the other hand, if it is detected that the boost amount y is small and the sound quality is insufficiently adjusted and the user operates the key to increase the boost amount y for the predetermined frequency band, the process proceeds to step SP6.

Here, the control circuit 4 calculates the current boost amount y
Is smaller than the attenuation x from the maximum output 0 [dB], but since the boost y is small, step SP7 is performed.
Increases the boost amount y.

On the other hand, the maximum output level (0 [dB])
If the volume level of the reproduced audio signal S1 is (−x2) and the attenuation amount x2 at this time is smaller than the maximum value B of the boost amount that can be adjusted by the sound quality adjustment circuit 3, the control circuit 4 The sound volume of the reproduced audio signal S1 is increased so that the boost amount y does not exceed the dynamic range.

At this time, the control circuit 4 performs steps SP1 to SP1.
If it is detected in step SP4 that the user has operated the key so as to decrease the boost amount y for the predetermined frequency band as being too large, the process proceeds to step SP5. Here, the control device 4 outputs a volume control signal S2 to the volume adjustment circuit 2 to hold or increase or decrease the volume level to the attenuation amount x specified by the user.

Further, the control circuit 4 outputs a sound quality adjustment signal S3 to the sound quality adjustment circuit 3, and reduces the boost amount y from the current value by a predetermined number of steps. On the other hand, if it is detected that the boost amount y is small and the sound volume adjustment is insufficient, and it is detected that the user has performed a key operation to increase the boost amount y for the predetermined frequency band, the process proceeds to step SP6.

Here, the control device 4 determines the current boost amount y
Is smaller than the attenuation x from the maximum output 0 [dB], and the process proceeds to step SP7 where a positive result is obtained. As shown in FIG. 3, since the maximum level B1 that can be currently taken as the boost amount y matches the attenuation amount x, the control circuit 4 determines that the current boost amount y is smaller than the attenuation amount x,
The boost amount y is increased according to the user's specification.

On the other hand, when the current boost amount y is not smaller than the attenuation amount x, that is, when the current boost amount y is equal to the attenuation amount x, the controller 4 sets the boost amount y regardless of the user's designation. When the sound quality is adjusted while maintaining the current value without increasing the audio signal S4, the adjusted audio signal S4 can be prevented from exceeding the dynamic range.

According to the above configuration, the audio signal S1
By narrowing the maximum adjustment range of the boost amount y in accordance with the attenuation x with respect to the maximum output 0 [dB], it is possible to reduce the head margin for volume adjustment which was conventionally required, and to reduce the volume adjustment range. The maximum output range can be expanded to 0 [dB]. In addition, since the volume adjustment range can be widened, the S / N can be improved, and the sound quality of the reproduced sound can be further improved.

In the above-described embodiment, the case where the present invention is applied to a sound volume and sound quality adjusting device in an in-vehicle audio device has been described. However, the present invention is not limited to this, and is applied to a sound volume and sound quality adjusting device of various audio devices. be able to.

In the above embodiment, the case where the volume level is adjusted by the control circuit 4 which is common to the volume adjustment circuit 2 and the tone quality adjustment circuit 3 has been described. However, the present invention is not limited to this. Also, a control device may be provided for each sound quality adjustment circuit 3 and the control devices may be connected to each other by a data bus.

Further, in the above-described embodiment, the case where the sound quality adjusting circuit 3 uses the equalizer for increasing or decreasing the volume level for each predetermined frequency band has been described. However, the present invention is not limited to this, and the present invention is not limited to this. A device that can adjust the volume level over a wide range may be used.

Further, in the above-described embodiment, the case where one sound quality adjustment circuit 3 is controlled by the control circuit 4 has been described. However, the present invention is not limited to this, and the case where a plurality of sound quality adjustment circuits 3 are controlled is described. It can also be applied to

[0039]

As described above, according to the present invention, the amount of attenuation of the volume level output from the volume control device with respect to the maximum output level is detected, and the volume level amplification correction designated and input to the sound quality control device is determined. If the attenuation does not exceed the specified input volume level, the volume level is amplified and corrected and output, and if the volume level amplification correction specified and input to the sound quality control device exceeds the attenuation, By suppressing the amplification correction charge by the amount of attenuation, the adjustment range of the sound volume level output from the sound volume adjustment device can be expanded to the maximum output range. As a result, the signal-to-noise ratio can be increased, and an audio signal with good sound quality can be output.

[Brief description of the drawings]

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

FIG. 2 is a flowchart for explaining the operation of the control device.

FIG. 3 is a schematic diagram for explaining a sound quality adjustment range.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Audio device, 2 ... Volume adjustment circuit, 3 ... Sound quality adjustment circuit, 4 ... Control device, 7 ... Key operation part.

Claims (1)

(57) [Claims] A volume adjusting means for adjusting the volume level according to claim 1 input audio signal, a predetermined amount amplify or reduce the volume level of the out stations <br/> constant frequency band of the output audio signal outputted from the volume adjustment means This
And by the tone control hand <br/> stage to adjust the sound quality of the output audio signal, based on the input operation of the user in the operation unit, the output sound
The voice signal has the maximum dynamic range of that volume level.
Detects the amount of attenuation from the force level and
Volume level of the predetermined frequency band in the output audio signal
Volume level amplification correction to amplify or reduce
And the detected level of attenuation and volume level
Frequency band of the output signal based on the amount of amplification
Control means for amplifying or reducing the volume level of the region by a predetermined amount;
The control means is controlled by the sound quality adjusting means.
The adjusted amplification level of the volume level exceeds the attenuation level.
If not, the sound quality is adjusted by the sound quality adjustment means.
Amplifying the volume level of the predetermined frequency band,
Of the volume level adjusted by the sound quality adjusting means.
If the amount of amplification correction exceeds the amount of attenuation, the amount of attenuation
Amplify the volume level of the predetermined frequency band by
Volume control apparatus, characterized in that that.