JPH02233008A - Sound quality correction device - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention is directed to Ode. The present invention relates to a sound quality correction device such as an audio device.

2. Description of the Related Art Conventional sound quality correction devices are often used as part of audio equipment.

An example of the conventional sound quality correction device mentioned above will be described below with reference to the drawings.

FIG. 3 shows a part of the configuration of a conventional sound quality correction device. In FIG. 3, 1 is a signal input terminal, and 6 is a graphic equalizer for adjusting the levels of a plurality of frequency bands and correcting frequency characteristics. 21 is a volume for adjusting the volume. 18 is a low-pass filter, 19 is a level adjustment circuit that operates inversely to the volume 21, 20 is an adder circuit, 4 is a power amplifier, and 5 is a speaker.

The operation of the sound quality correction device configured as described above will be explained below.

The signal input from input terminal 1 is a graphic equalizer.
At step 6, the frequency characteristics are adjusted to the user's arbitrary frequency characteristics, and the volume is adjusted to an arbitrary volume at the volume 21, and then input to the adding circuit 20. In addition, in order to correct the fact that bass sounds are difficult to hear at low volumes, the output of the volume 21 is also input to a low-pass filter 18, and the low-frequency components are passed to the level adjustment circuit 18.
9 and is added to the original signal in an adder circuit 2o. Here, the level adjustment circuit 19 is linked inversely to the volume 6, so when the set level of the volume 21 is high, the output level of the level adjustment circuit 19 is low, and conversely, when the set level of the volume 21 is low, the output level of the level adjustment circuit 19 is low. , the output level of the level adjustment circuit 19 is increased. Therefore, adder circuit 2
When the set level of the volume 21 is low, the low range of the output of o is enhanced, and when the set level of the volume 21 is high, the low range enhancement level becomes small. FIG. 4 schematically shows the frequency characteristics at this time.

Problems to be Solved by the Invention However, in the above configuration, although the level of low-frequency enhancement changes depending on the setting level of the volume 21, the characteristics of the low-pass filter 18 do not change, so the Nakagusuku component is also increased more than necessary. There were cases where the sound quality was unnatural, such as being enhanced at the same time. Furthermore, when the volume is low, it becomes difficult to hear both bass and treble sounds, but in order to make this kind of correction, it is necessary to make corrections that create more complex frequency characteristics depending on the volume level.

Further, there is a problem that the correction curve for the frequency characteristics at low volume cannot be handled by a single correction curve due to large individual differences among users.

The present invention solves the above-mentioned problems by more finely correcting the insufficient bass and treble at low volumes, and furthermore allows the user to select from not only a single correction curve but also multiple correction curves. This eliminates individual differences in hearing perception,
To provide a sound quality correction device with excellent sound quality from low volume to high volume at low cost.

Means for Solving the Problems In order to solve the above problems, the sound quality correction device of the present invention has the following features:
The present invention includes a storage means for correcting the frequency characteristics of the electronic graphic equalizer in accordance with a set level of an electronic volume for adjusting the sound volume, and a control means.

According to the above-described configuration, the present invention can easily realize a complex correction curve by storing correction values for the frequency characteristics of the electronic graphic equalizer corresponding to the set level of the electronic volume in the storage means, thereby achieving excellent sound quality. is obtained.

Furthermore, it can be realized at low cost by using an electronic graphic equalizer that is normally used for correcting sound quality, without using a filter circuit or the like for correction of small sound scenes.

Embodiment Hereinafter, a sound quality correction device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 shows the configuration of a sound quality correction device in an embodiment of the present invention. In Figure 1, 1 is an input terminal, 2 is an electronic graphic equalizer that can electrically control the levels of multiple frequency bands and obtain arbitrary frequency characteristics, and 3 is an electronic that can electrically control the volume level. Volume, 4 is power amplifier, 5 is subi-
16 is a display section for displaying the frequency characteristics of the electronic graphic equalizer; 16 is a display section for displaying the set level of the electronic volume; 13 is an input key switch for varying the frequency characteristics of the electronic graphic equalizer. , 14 are input keys for varying the electronic volume. 17 is an input key switch for the user to select a correction value for correcting the frequency characteristics at low volume from a plurality of characteristics; 7 is a microcomputer, and the graphic equalizer corresponds to the setting level of the electronic volume 3; a read-only memory (ROM) 9 having data such as correction values of the electronic graphic equalizer 2, a random access memory (RAM) 10 capable of temporarily storing setting data of the electronic graphic equalizer 2, setting data of the electronic volume 3, etc.; ROM9 and RAM1o
an arithmetic unit 11 that reads and compares the contents of the electronic graphic equalizer 2, adds correction data for the set level of the electronic volume 3 to the current characteristic data of the electronic graphic equalizer 2, and determines actual control data of the electronic graphic equalizer; , an input section 12 such as an input key switch, and an output section 8.

FIG. 2 is a flow chart of essential parts for explaining the operation of the microcomputer 7 of this embodiment.

The sound quality correction device configured as above will be described below with reference to FIGS. 1 and 2.

A signal input from an input terminal 1 has its frequency characteristics adjusted by an electronic graphic equalizer 2, its volume is adjusted by an electronic volume 3, is amplified by a power amplifier 4, and is reproduced from a speaker 6.

Here, the electronic graphic equalizer 2 allows the user to obtain arbitrary frequency characteristics in the same way as a normal graphic equalizer by operating the graphic equalizer input keys. Furthermore, in addition to the above functions, under the control of the microcomputer 7, according to the set level of the electronic volume 3, the frequency characteristics can be corrected to enhance the bass and treble at low volumes and achieve excellent characteristics. It has a so-called loudness function. Further, the user can select and use the loudness correction characteristic from a plurality of correction characteristics by operating the correction curve selection input key switch.

Next, let's talk about the control of the microcomputer 7. This will be explained using the flowchart shown in FIG.

First, when the power of this device is turned on, the program is started, and the initial settings in step 23 of the flowchart are performed. This sends data to electronic graphic equalizer 2 and electronic volume 2. This is to obtain a certain frequency characteristic and volume. At the same time, data is sent to the graphic equalizer display section 16 and the volume display section 16 so that a display corresponding to the frequency characteristics and volume can be displayed. This initialization data is stored in the ROM 9 as initialization data, enters the arithmetic unit through 9ya, and outputs sa, sb, ac,
Each sword will be issued by sci.

Next, in step 24, key manual processing is performed, and inputs are made using the input section 12 through the graphic equalizer input key switch 13, the volume input key switch 14, and the correction curve selection input key switch 170. The input state is temporarily stored in the RAM 10 from step 12t).

Next, the steno knob 26 checks whether or not the correction gap selection switch has been pressed as a result of the key manual processing in step 24. Here, for this correction curve, a plurality of groups of combinations of data of the electronic graphic equalizer 2 corresponding to the setting level of the electronic volume 3 are stored in advance in the ROM 9. Furthermore, which group is currently being used is stored in the RAM 1o as group 5. If there is a change in the correction curve in step 26, then in step 26 the correction curve is changed. This is to perform the above-mentioned group black change in RAM10. If there is no change in the correction curve or if the processing in step 26 is completed, the process advances to the next step 27.

In step 27, a change in volume is checked based on the processing result of step 24. If the volume is to be changed, the volume setting value data stored in the RAM 10 of the step 28 is changed, and in step 29, the R
The data of the volume setting value of AM10 is inputted to the output section 8 through 10&. The electronic volume setting value is changed through 8G from the output section 8 to change the volume, and 8d
The display of the volume display 16 can be changed through.

Further, the process proceeds to step 33, in which the group black of the correction data described above is first stored in the RAM in order to correct the graphic equalizer for the volume setting value described above.
The current volume setting value data is called from RAM10. Then, from the ROM 9, group 5 and the volume setting value are specified, and data of the correction value of the graphic equalizer for the current volume setting value is called to the calculation unit 11 through 911.

Furthermore, in step 34, control data for obtaining the frequency characteristics of the electronic graphic equalizer 2 arbitrarily set by the user is called from the RAM 10 to the calculation unit 11.
This is added to the correction data based on the volume setting value described above.

Then, obtain the setting values for each frequency band of the actual electronic graphic equalizer. For example, frequency 100Hz
If the correction value for the volume setting value is +3 dB and the setting value of electronic graphic equalizer -2 set by the user is +2 dB, +3 dB + (+2 dB) = +5 dB, and the actual setting value of electronic graphic equalizer -2 is +6 dB. Become.

In the next step 36, based on the calculation result of step 34, the output 111L of the calculation part 11 is inputted to the output part 8, and the electronic graphic equalizer 2 is controlled by this output 8b, so that the frequency characteristics based on step 34 are obtained. Become.

Also, if there is no change in volume on Stenop 2A,
Proceed to step 30 and check whether the settings of Graphic Ifriser have been changed. If there is a change, the setting value is changed in step 31.
This is done by changing the setting value data of the 0 graphic equalizer.

Next, in step 32, the setting value data of the graphic equalizer in step 31 is outputted from RAM10.
The signal is inputted to the output section through 81, and inputted from the output section to the graphic equalizer display section 16 to change the display. Further, the process advances to step 33, where the same processing as that for changing the volume described above is performed, and after adding a correction value to the volume setting value, data is sent to the electronic graphic equalizer 2 to change the frequency characteristics.

If there is no change in step 3o, or if the processing in step 36 described above is completed, the process proceeds to step 3e.

Step 36 is other processing that is not directly related to sound quality correction, and when this processing is completed, the process returns to step 24, which is manual key processing, and the above-mentioned processing is repeated.

As described above, according to this embodiment, a plurality of correction values for the electronic graphic equalizer are provided for the volume setting value, and the user can select them, thereby adjusting the treble at low volumes due to individual differences. It eliminates the difficulty of hearing bass sounds and reproduces sound with excellent characteristics from low volumes to high volumes.

Effects of the Invention The present invention uses an electronic graphic equalizer and an electronic volume in combination, and uses the electronic graphic equalizer to finely correct the frequency characteristics with respect to the set value of the electronic volume. This makes it possible to correct sound quality and at the same time eliminate the need for a conventional loudness circuit, making it possible to provide an excellent sound quality correction device at a lower cost.

[Brief explanation of the drawing]

Fig. 1 is a block configuration diagram of a sound quality correction device according to an embodiment of the present invention, Fig. 2 is a flowchart of the main part of the operation explanation in an embodiment of the present invention, and Fig. 3 is a block diagram of a conventional sound quality correction device. The configuration diagram, FIG. 4, is a schematic diagram of frequency characteristics of a conventional sound quality correction device. 1...Input terminal, 2...Electronic graphic equalizer, 3...Electronic volume, 4
...Power increase 11itL5...Speaker, 7...Microcomputer. Name of agent Patent attorney Shigetaka Awano Idiot 1 Figure 1

Claims (1)

[Claims] An electronic graphic equalizer that electrically independently controls the levels of a plurality of frequency bands, an electronic volume that electrically varies the output level, and a set level of the electronic volume and the electronic equalizer that corresponds to the set level of the electronic volume. A storage means that stores a combination of correction values of the graphic equalizer, a set level of the electronic volume and a set level of the electronic graphic equalizer, and calculates the stored content and the stored content of the storage means. A sound quality correction device comprising: a control means capable of outputting an output corresponding to a setting position of an electronic volume to the electronic graphic equalizer.