JP3243737B2 - Volume control circuit device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound volume adjusting circuit device for automatically adjusting a sound volume level suitable for use in a reproducing apparatus for reproducing a plurality of music sources such as a cassette tape, a compact disk, and a music broadcast. is there.

[0002]

2. Description of the Related Art FIG. 4 is a block diagram showing a configuration of a reproducing apparatus having a function of reproducing a plurality of music sources such as music and voice from a cassette tape, a compact disk, a music broadcast or the like. In the figure, 1 is a tuner for selecting a radio broadcast, 2 is a compact disc as a music source on which music and voice are recorded, 3 is a reproducing tape on which music is recorded, and 4 is a recording tape. This is a recording tape used when performing. Reference numeral 5 denotes a drive mechanism for driving the compact disk 2, the reproduction tape 3, and the recording tape 4. Reference numeral 6 denotes a signal switching unit, which is a circuit for switching a signal output from the tuner 1, the compact disk 2, or the reproduction tape 3. Reference numeral 7 denotes an electronic volume that varies the internal resistance and varies the level of an output signal with respect to an input signal. Reference numeral 8 denotes a volume drive motor that drives the electronic volume 7.

Reference numeral 9 denotes a preamplifier for performing equalization and amplification on an input signal, and reference numeral 10 denotes a power amplifier. 11 is a level detection circuit for detecting the output of the electronic volume 7,
This circuit supplies a detection output to the microprocessing unit 12. Microprocessing unit 12
Controls the volume drive motor 8 and the drive mechanism 5. An operation panel 13 has a volume down key 14, a volume up key 15, and the like.

This reproducing apparatus has a function of automatically adjusting the recording level only when recording on the recording tape 4.

[0005]

In the above-described reproducing apparatus, when signals supplied from a plurality of music sources such as a cassette tape, a compact disk, and a music broadcast are reproduced, the signals are recorded on the cassette tape or the compact disk. Since the level of the received signal and the signal level of the received music broadcast are different from each other, the following problems have been encountered. That is, for example, when listening on a compact disc and then listening to a cassette tape, the signal level is different, so the volume must be operated each time.

SUMMARY OF THE INVENTION The present invention has been made to solve the above problems, and has a volume control circuit device capable of obtaining an output of a desired volume level regardless of the level of a signal supplied from a music source. The purpose is to obtain.

[0007]

A volume control circuit device according to the present invention comprises volume level control means having a volume for changing the levels of signals supplied from a plurality of music sources, and a signal output from the volume. To detect
Accordingly, a level detecting circuit for detecting the level of the signal output from the volume, and volume memory keys for setting the volume level of preference for reproducing a signal supplied from said plurality of music source, the volume memory key And a memory for storing a volume level set by the volume control unit, wherein the volume level control means includes an internal resistance of the volume based on the level of the signal detected by the level detection circuit and the volume level stored in the memory. By changing the value, the level of the signal supplied from the plurality of music sources is automatically adjusted, and the volume when each of the signals supplied from the plurality of music sources is reproduced is controlled to the desired volume level. .

[0008]

The volume control circuit device according to the present invention detects a level of a signal output from a plurality of music sources and, when reproducing a signal output from the music source, sets a desired volume at which the volume level is set. The level of the signal supplied from the music source is automatically adjusted to the level, so that the output of the set desired volume level can be obtained regardless of the level of the signal of the music source. To

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings. FIG. 1 is a block diagram showing the configuration of a volume control circuit device according to the present embodiment. In FIG. 1, the same or corresponding parts as those in FIG.

In the figure, a level detection circuit 11 detects the output of an electronic volume 7 (volume level control means), and outputs a signal from a plurality of music sources such as music and voice from a compact disk 2, a reproduction tape 3 or a music broadcast. The signal level is being detected. 12a is a ROM included in the microprocessing unit 12 (volume level control means)
The program shown in the flowchart of FIG. 2 is stored. Similarly, reference numeral 12b denotes a RAM included in the microprocessing unit 12. Reference numeral 16 denotes a volume memory key operated by the user when setting the maximum volume level A of a desired volume.

Next, the operation of the volume setting process for automatically adjusting the volume level will be described with reference to the flowchart shown in FIG. First, the volume memory key 16 for setting the volume to a desired level is operated.
It is determined whether or not the maximum volume level A has been set (step S1). When it is determined that the operation of the volume memory key 16 is not performed, the process returns to the program address before the volume setting process. When it is determined that the volume memory key 16 has been operated and the maximum volume level A has been set, the maximum volume level A is stored in the RAM 12b of the microprocessing unit 12 (step S).
2).

When the processing in step S2 is completed, the volume down key 14 or the volume up key 15
Is determined (step S3), and the volume down key 14 or the volume up key 15
Is determined, the maximum volume level A stored in the RAM 12b is cleared, and the program returns to the program address before the volume setting process (step S).
4). When it is determined that the volume down key 14 or the volume up key 15 is not depressed, the maximum level X of the signal output from the music source at that time detected by the level detection circuit 11 at that time is determined.
And a value (A-α) obtained by subtracting the minimum adjustment unit level α from the maximum volume level A stored in the RAM 12b (step S5). As a result of this comparison, X = (A-α), that is, the minimum adjustment unit level α was subtracted from the maximum level X of the signal output from the music source and the maximum volume level A stored in the RAM 12b. If the values (A-α) are equal, it is considered that the maximum volume level A of the desired volume set by the user is satisfied by the volume level output from the speaker (not shown), and the process returns to step S3.

On the other hand, if the result of comparison in step S5 is X <(A
-Α), ie, the signal output from the music source
Is stored in the RAM 12b.
The minimum adjustment unit level α has been reduced from the maximum volume level A.
When the value is smaller than the value (A-α),
The level of the volume output from the
The sound output from the speaker, assuming that it falls below A
Adjust the level of quantity so that it is increased by the minimum unit level α
Controls the volume drive motor 8volume
(Volume) Adjusted to reduce the internal resistance of 7
Is performed (step S6), and the process returns to step S3.

On the other hand, if the comparison result in step S5 is X> (A
-Α), that is, when the maximum level X of the signal output from the music source is larger than the value (A-α) obtained by subtracting the minimum adjustment unit level α from the maximum volume level A stored in the RAM 12b. The maximum level X of the signal output from the music source;
A comparison is made with a value (A + α) obtained by adding the minimum adjustment unit level α to the maximum volume level A stored in b (step S7). The result of this comparison is X> (A +
α), that is, when the maximum level X of the signal output from the music source is larger than the value (A + α) obtained by adding the adjustment minimum unit level α to the maximum volume level A, the level of the volume output from the speaker is The volume drive motor 8 is controlled so that the level of the volume output from the speaker is reduced by the adjustment minimum unit level α, assuming that the maximum volume level A is exceeded, so that the internal resistance value of the electronic volume 7 is increased. Adjustment is performed (step S8), and the process returns to step S3.

In step S7, X <(A + α),
That is, the maximum level X of the signal output from the music source
Is smaller than the value (A + α) obtained by adding the minimum adjustment unit level α to the maximum volume level A stored in the RAM, the level of the volume output from the speaker satisfies the maximum volume level A. And returns to step S3. After returning to step S3, the operation after step S3 described above is repeated.

As a result, the maximum level X of the signal output from the music source is obtained by subtracting the minimum adjustment unit level α from the maximum volume level A stored in the RAM (A
−α) and a value (A + α) obtained by adding the minimum adjustment unit level α to the maximum volume level A, it is determined that the volume level output from the speaker satisfies the maximum volume level A. It is regarded.

The maximum level X of the signal output from the music source is a value (A-α) obtained by subtracting the minimum adjustment unit level α from the maximum volume level A stored in the RAM.
If it is smaller, the level of the volume output from the speaker is considered to be lower than the maximum volume level A of the desired volume set by the user, and the electronic volume 7 is adjusted to increase the volume level by adjusting the minimum unit level α. Each time the volume down key 14 or the volume up key 15 is pressed, or a value obtained by subtracting the minimum adjustment unit level α from the maximum volume level A (A−α).
Are adjusted step by step until the value reaches a value (A + α) obtained by adding the minimum adjustment unit level α to the maximum volume level A.

When the maximum level X of the signal output from the music source is larger than the value (A + α) obtained by adding the minimum adjustment unit level α to the maximum volume level A, the level of the volume output from the speaker is changed by the user. And the electronic volume 7 is adjusted so as to lower the volume level by the volume down key 1 for each minimum unit level α.
4 or the volume up key 15 is pressed, or a value (A-α) obtained by subtracting the minimum adjustment unit level α from the maximum volume level A, and the minimum adjustment unit level α is added to the maximum volume level A. It is adjusted step by step until it falls between the values (A + α) and repeated.

When the electronic volume 7 is adjusted step by step for each minimum adjustment unit level α, a saturation characteristic may be provided such that the volume level does not change any more when the number of adjustments reaches a predetermined number. . Also, if the minimum adjustment unit α is too small, automatic adjustment will always work, so that the change in volume will not be calm,
On the contrary, it is more difficult to hear, so it is better that the unit α is an appropriately large value. Further, the value of α may be changed by manual input. The block diagram in that case is as shown in FIG. Reference numerals 20 and 21 denote up-down keys for changing the setting of α.

[0020]

As described above, according to the present invention, even when a plurality of music sources are to be reproduced, the output of a desired volume level can be stably obtained without setting the volume by the volume each time. Has the effect.

[Brief description of the drawings]

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

FIG. 2 is a flowchart showing an operation of the volume control circuit device according to one embodiment of the present invention.

FIG. 3 is a block diagram showing another embodiment.

FIG. 4 is a block diagram showing a configuration of a conventional reproducing apparatus having a function of reproducing a plurality of music sources.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Tuner 2 Compact disk 3 Playback tape 4 Recording tape (music source) 7 Electronic volume 11 Level detection circuit 12 Microprocessing unit (volume level control means) 12b RAM 16 Volume memory key

Continuation of the front page (58) Field surveyed (Int.Cl. ⁷ , DB name) H04R 3/00 310 G11B 20/04 101 H03G 1/00 H04R 3/04 H04S 7/00

Claims (1)

(57) [Claims] 1. A volume level control unit having a volume for changing the level of a signal supplied from a plurality of music sources, and detecting a signal output from the volume.
Ri, a level detecting circuit for detecting the level of the signal output from the volume, and volume memory keys for setting the volume level of preference for reproducing a signal supplied from said plurality of music source, the volume memory key And a memory for storing a volume level set by the volume control unit, wherein the volume level control means includes an internal resistance of the volume based on the level of the signal detected by the level detection circuit and the volume level stored in the memory. By changing the value, the level of the signal supplied from the plurality of music sources is automatically adjusted, and the volume when each of the signals supplied from the plurality of music sources is reproduced is controlled to the desired volume level. A volume control circuit device characterized by the above-mentioned.