JPH02228200A - TV set with built-in sound reproduction system - 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 relates to a television set with a built-in sound reproduction system that matches images on a large-screen television.

Conventional Technology In recent years, a large number of movie software, typified by video and laser discs, have become available. In addition, as TV screens have become larger, it has become possible to experience the power and presence of movie theaters even in the comfort of your own home. In line with this trend, development of sound reproduction systems for televisions that match large-screen images is underway.

The configuration of a conventional TV set with a built-in sound reproduction system,
This will be explained below with reference to the drawings.

FIG. 2 shows the configuration of a conventional television set with a built-in sound reproduction system. In Fig. 2, 1 is an audio signal input means, 2 is a channel splitter, 3 is an amplifier, 4 is a left (L) channel speaker, 5 is a (R) right channel speaker, and 6 is a center (C) channel speaker. This is a speaker for use.

The operation of the conventional television set with a built-in sound reproduction system configured as described above will be described below.

A signal inputted by the audio signal input means 1 is split into R and C signals by a splitter 2. The C channel signal is amplified by an amplifier 2 and reproduced by a C channel speaker 6 placed below the television screen. Also,
The input and R signals are amplified by an amplifier 3 and then reproduced by an L channel speaker 4 and an R channel speaker 5, respectively. In this way, by reproducing the R signal not only from the R channel speaker but also from the C channel speaker, the effect of sound image localization can be improved compared to the case where the C channel speaker is not used. I was able to increase it.

Problems to be Solved by the Invention However, with the above configuration, it is necessary to have a C channel speaker that reproduces an audio signal of 207 to 20 KHz without any discomfort and has a wide directional characteristic so that the sound quality does not change depending on the listening position. However, for this reason, in order to incorporate the C channel speaker into the TV box, the TV box had to be made larger. Furthermore, there is a problem in that the sound image is localized below the television screen, and a sense of spaciousness cannot be obtained when the signal is reproduced using only the C channel speaker.

In view of the above-mentioned problems, the present invention includes a band pass device that extracts only a certain band of a signal to be reproduced from a C channel speaker, a band rejector that extracts other bands, and a band pass filter that outputs the output of the band pass device from a C channel speaker. By using the output of the band rejecter and reproducing it through the R channel speaker, a sense of spaciousness can be obtained without impairing the sound image localization effect compared to when band division is not performed, and the C channel speaker can be made smaller. The present invention provides a television set with a built-in sound reproduction system that can be built into a television box.

Means for Solving the Problems In order to solve this object, the television set with a built-in sound reproduction system of the present invention is constructed as follows.

a left channel speaker, a right channel speaker, a center channel speaker having an acoustic radiation surface at the bottom center of the brown can, a bandpass device for extracting only a certain frequency band of a signal to be reproduced by the center channel speaker; A band-elimination device is provided for extracting other frequency signals not included in the band-pass device, and the output of the band-pass device is power-amplified and then applied to a center channel speaker, and the output of the band-pass device is gain-adjusted. ,
Adds the signal played by the left and right channel speakers,
The configuration is such that the power of the added signal is amplified and applied to the left and right channel speakers.

There is a bandpass device that takes out only a certain band of the signal to be reproduced from the C channel speaker, a band rejector that takes out the other bands, and the output of the band pass is sent to the C channel speaker, and the output of the band rejector is sent to the C channel speaker. By using the R channel speaker for playback, you can obtain almost the same sense of sound localization and spaciousness as when no band division is performed, and the C channel speaker can be made smaller. This makes it possible to incorporate a C channel speaker at the TV center position where a natural sense of sound localization can be achieved.

EXAMPLE Hereinafter, an example of the present invention will be described with reference to the drawings. FIG. 1 shows an embodiment of the present invention as set forth in claim (1).

In FIG. 1, 1 is an audio signal input means, 2 is a channel splitter, 3 is a gain adjuster, 4 is an L channel speaker, 5 is an R channel speaker, 6 is a C channel speaker, 7 is an amplifier, and 8 is a band pass, 9 is a band reject, and IO is an adder.

The audio signal input by the audio signal input means 1 is sent to the channel demultiplexer 2.

The signal is split into R and C signals. A certain frequency band of the C signal to be reproduced by the C speaker is extracted by a bandpass device 8, amplified by an amplifier 7, and reproduced by a C channel speaker 6. Further, the C signal inputted to the band rejecter 9 has a band other than the band pass filter extracted, and the gain is adjusted by the gain adjuster 3 in order to adjust the efficiency of the speaker system. The gain-adjusted signals are L channel signals,
It is added with the R channel signal in the addition 2S10, and the amplifier 7
After being amplified, the signal is reproduced from the L channel speaker 4 and the R channel speaker 5.

In this way, by band-limiting the signal to be reproduced by the C-channel speaker, the C-channel speaker can be made smaller in size, and when played back at the same time as the video, a sound image localization feeling that does not feel out of place with the video can be achieved. It becomes possible to incorporate a C channel speaker in the position of the television center that can realize this.

FIG. 3 shows the configuration of a band pass device and a band reject device according to claim 2. In Figure 3, 1
1 is a low pass filter (hereinafter referred to as LPF), and 12 is a high pass filter (hereinafter referred to as HPF).

A C channel signal to be reproduced by the C channel speaker is input to the LPF II and HPF 12. Here, it is divided into a low frequency band that does not affect sound image localization and a higher frequency band. The output of the HPF 12 is reproduced from the C channel speaker, and distributed to the LPF II output and the R channel speaker. In this case LPF 11
．． The cutoff frequency (fcl) of HPF12 was found to be approximately 200 Hz to 300 Hz from the results of psychoacoustic experiments.

Next, a psychoacoustic experimental method for determining the cutoff frequency (fcl) will be described below.

FIG. 4 is a block diagram of an experimental apparatus for determining the cutoff frequency (f c 1). 13 is an audio signal input means, 14 is an L channel speaker, 15 is an R channel speaker, 16 is a C channel speaker, 17
is a gain adjuster, 20 is an amplifier, 18 is an LPF, 19 is an H
It is PF.

The signal input to the audio signal input means 13 is LPF
The signal is divided into a band above fc1 and a band below fc by the HPF 19. The signal that has passed through LPFlB has its gain adjusted by a gain adjuster 17, is amplified by an amplifier 20, and is reproduced from an R channel speaker. HPF1
The signal passing through C channel 9 is amplified by amplifier 20 and reproduced from the C channel speaker. Subjects were free to use LPF.

The cutoff frequency (fcl) of the HPF can be changed in conjunction. What the subject is required to do here is to demonstrate the maximum fclO value at which the sound image does not deviate from the center. The distance between the L and R channel speakers is 0.
In the range of 5 m - 1,2 m, the listening position is a general listening position at a viewing angle of 20°. The experiment was also conducted in a typical audio listening room in a Western-style room. The signal is a reading by a male and female announcer recorded in an anechoic chamber.

The experimental results are shown in Table 1.

(Margin below) Table As a result, it was found that the value of fcl was in the range of 200)(z ~ 300Hz. In this way, the value of fcl was found to be in the range of 200) (z ~ 300Hz).
By reproducing signals above z by the C channel speaker, and distributing signals below that to the R channel speaker for reproduction, the same level of sound image localization effect as when no band limitation is applied can be obtained. The channel speakers can be made smaller, and when played at the same time as the video, the C-channel speaker is placed in a position on the TV set that allows for sound image localization that does not feel out of place with the video.
It becomes possible to incorporate a channel speaker.

FIG. 5 shows the configuration of a band pass device and a band reject device according to claim 3. In Figure 5, 1
1 is a low pass filter (hereinafter referred to as LPF), 12 is a high pass filter (hereinafter referred to as HPF), and the C signal to be reproduced by the C channel speaker is LPFI l,
Manually powered by HPF12. Here, it is divided into a high frequency band that has little effect on sound image localization and provides a sense of spaciousness, and a lower frequency band. The output of LPFII is then played back by the C channel speaker, and the output of HPF12 and R
Distributed to channel speakers.

In this case, the cutoff frequency of LPFII and HPF12 (
fc2) is approximately 3KHz to 6 from the results of psychoacoustic experiments.
It turned out to be KHz.

A psychoacoustic experimental method for determining the cutoff frequency (fc2) will be described below.

FIG. 6 is a block diagram of an experimental apparatus for determining the cut-off frequency (fc2). 13 is an audio signal input means, 14 is an L channel speaker, 15 is an R channel speaker, 16 is a C channel speaker, 17 is a gain adjuster, 20 is an amplifier, 18 is an LPF, and 19 is an HP
It is F.

The signal input to the audio signal input means 13 is LPF
I8. The HPF 19 divides the signal into a band above fc2 and a band below fc2. The signal that has passed through the HPF 19 is gain adjusted by a gain adjuster 16, amplified by an amplifier 20, and reproduced from an R channel speaker. LPFI8
The signal passing through is amplified by an amplifier 20 and reproduced from a C channel speaker. What should be found here is a value of fc2 that provides a sense of sound image localization and a sense of spaciousness. The experimenter arbitrarily determines the cutoff frequency (f c 2) and presents the signal to the subject. Subjects responded to the presented signal with a range of categories shown in Table 2 (here, 0: same, 1
There were four levels: 1: Fairly good, 2: Quite good, and 3: Very good. ).

Table 2 The distance between the L and R speakers and the listening position are the same as the experimental conditions for determining fcl. Additionally, the experiment was conducted in an anechoic chamber. As a result, it was found that the value of fc2 that provides a certain degree of localization and a sense of spaciousness is in the range of 3 KHz to 6 KHz. In this way, signals with a frequency of 3KHz to 6KHz or less that should be played back from the C channel speaker are played back by the C channel speaker, and signals above that frequency are distributed and played back to the L and R channel speakers, thereby preventing them from being distributed. In this case, it is possible to obtain the effect of localizing the center sound image of the audio signal to the same extent as in the case where the center sound image is localized, and also to obtain a sense of spaciousness.

FIG. 7 shows the configuration of a band pass device and a band reject device according to claim 4. In Figure 7, 2
1 is a band pass filter (hereinafter referred to as BPF), and 22 is a band rejection filter (hereinafter referred to as BEF). The C channel signal to be played by the C channel speaker is BP.
A 3KHz to 6KHz signal is extracted from the 2507 by F21 and reproduced by the C channel speaker. In addition, the output of the BEF 22 for other bands is distributed to the R channel speaker. In this way, 250H of the signal to be reproduced from the C channel speaker
7 to 6 KI from z to 3 (bandpass device that extracts the z signal and reproduces it with the C channel speaker, and distributes the other bands and distributes them to the R channel speaker for reproduction,
By providing a band stopper and a band stopper, it is possible to obtain almost the same sense of sound localization and spaciousness as when no band restriction is applied to the C signal, and the speaker for the C channel can be made smaller. This makes it possible to incorporate a C channel speaker in a position on the television set that can provide a natural sense of sound and image localization.

Furthermore, by reproducing the entire band from the C channel speaker, it is possible to correct the phenomenon in which the sound image is located at the bottom of the screen.

Effects of the invention 25 Signals to be reproduced from the C channel speaker
By extracting only the band above 07 and reproducing it from the C channel speaker, and distributing the band below 250 and distributing it to the R channel speaker for reproduction, sound image localization can be achieved at almost the same level as when no band division is performed. To provide a sense of sound, to make the C channel speaker small, and to incorporate the C channel speaker in a position of a television set that can realize a sound image localization feeling that does not feel out of place with the video when played back simultaneously with the video.

In addition, by removing high-frequency components of 3KHz to 6KHz or more and distributing them to the R channel speaker, and reproducing the band of 3KHz to 6KHz or less using the C channel speaker,
By reproducing the entire band from the C channel speaker, it is possible to correct the phenomenon in which the sound image is located below the screen, and it is also possible to obtain a sense of spaciousness. Furthermore, by having a wide directional characteristic mainly in the horizontal direction and by using an R channel speaker, changes in sound quality depending on the listening position can be reduced.

[Brief explanation of the drawing]

FIG. 1 is a block diagram of a television set with a built-in sound reproduction system which is an embodiment of the present invention, FIG. 2 is a block diagram of a conventional television set with a built-in sound reproduction system, and FIG. 3 is an embodiment of the present invention. FIG. 4 is a block diagram of an experimental device for determining the cutoff frequency (f c 1), and FIG. 5 is a block diagram of a bandpass device that is an embodiment of the present invention. , Block diagram of bandstopper, No. 6
The figure is a block diagram of an experimental apparatus for determining the cut-off frequency (fc2), and FIG. 7 is a block diagram of a band pass filter and a band reject filter according to an embodiment of the present invention. 1.12... Audio signal input means, 2, 3
゜16.19...Amplifier, 4,13...
・Left (L) Chanful speaker, 5.14...
・Right (R) channel speaker, 6.15...
・Center (C) channel speaker, 7...
・Band pass device, 8...Band rejector, 9...
... Adder, 10.17 ... Low pass filter (LPF), 11.18 ... High pass filter (HP F). Name of agent Patent attorney Shigetaka Awano 1 person 1-m- O No. 4411 input +6 +3--- +4--- 15-・- +6 --- +7--- +9--- W-- O-ta Io priest J! Enter 71+6 Shisenya'7 Nell circle speaker R+ and Nell speed D C+ Yang Nell speaker 11! High 1kl'1Vha full 9 (LPF)

Claims (4)

[Claims] (1) A left channel speaker, a right channel speaker, a center channel speaker that has an acoustic radiation surface at the bottom center of the brown can, and a band pass that extracts only a certain frequency band of the signal to be reproduced by the center channel speaker. and a band-elimination device for extracting other frequency signals not included in the band-pass device, the output of the band-pass device is power-amplified and then applied to a center channel speaker, and the output of the band-pass device is applied to the center channel speaker. A television set with a built-in sound reproduction system characterized in that after adjusting the gain, the signal is added to the signal reproduced by the left and right channel speakers, and the power of the added signal is amplified and applied to the left and right channel speakers. (2) The bandpass device passes a band of 250Hz or higher,
2. The television set with a built-in sound reproduction system according to claim 1, wherein the sound range blocker blocks a frequency band of 250 Hz or more. (3) The television set with a built-in sound reproduction system according to claim 1, wherein the band pass device passes a band of 3 KHz to 6 KHz or less, and the band rejector blocks a band of 3 KHz to 6 KHz or less. (4) Bandpass is 250Hz to 3KHz to 6KHz
The band rejecter passes the band from 250Hz to 3KH.
2. The television set with a built-in sound reproduction system according to claim 1, wherein the television set has a built-in sound reproduction system.