JPH08186899A - Sound field controller - Google Patents

Abstract

(57) [Abstract] [Purpose] To provide a video display device with a sound field control device, which solves the problem of securing a space for speaker placement during surround sound reproduction and obtains a sufficient sound field effect. Structure: Virtual sound image generating means for surround channel audio, first speaker and second speaker for surround channel, speaker for left channel, speaker for right channel, first speaker for center channel, second speaker, video A display device is provided, and a first speaker for surround channels, a speaker for left channels, and a first speaker for center channels are sequentially arranged from the upper left side to the lower side of the video display device, and similarly for the surround channels on the right side of the video display device. The second speaker, the right channel speaker, and the center channel second speaker are arranged at the same height as the speakers corresponding to the respective channels arranged on the left side.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a sound field control device for surround sound reproduction composed of multiple channels by a plurality of speakers.

[0002]

2. Description of the Related Art FIG. 3 shows a reproduction system of surround sound of four channels output from a MUSE decoder. In FIG. 3, 24 is a MUSE decoder, 25 is a surround channel audio signal output from the MUSE decoder 24, 26 is a left channel audio signal output from the MUSE decoder 24, and 27 is a right channel output from the MUSE decoder 24. Audio signal, 28 is a center channel audio signal output from the MUSE decoder 24, 29 is an amplifier circuit for amplifying the surround channel audio signal 25, 30 is an amplifier circuit for amplifying the left channel audio signal 26, 31 is the right An amplifier circuit for amplifying the channel audio signal 27, 32 is an amplifier circuit for amplifying the center channel audio signal 28, 33
a is a first speaker for surround channel driven by the amplifier circuit 29, 33b is a second speaker for surround channel driven by the amplifier circuit 29, 34a is a speaker for left channel driven by the amplifier circuit 30, 34b Is a right channel speaker driven by the amplifier circuit 31, 35 is a center channel speaker driven by the amplifier circuit 32, 36 is a video signal output from the MUSEd decoder 24, and 37 is the video signal 36
Is a video display device such as a CRT for inputting, and 38 is a viewer or an audience.

Next, the operation of each part will be described. Four surround sound signals 25, 2 output from the MUSE decoder 24
6, 27, and 28 are independently amplified by amplifier circuits 29, 30, 31, and 32, and the surround channel audio signal 25 is supplied to the left channel audio signal 26 by the surround channel first speaker 33a and the surround channel second speaker 33b. The left channel speaker 34a converts the right channel audio signal 27 into a right channel speaker 34b, and the center channel audio signal 28 into a center channel speaker 35. Further, the video signal 36 is converted into a video by the video display device 37. As a result, the viewer perceives the actual sound image of the left channel sound, the center channel sound, and the right channel sound at the position of the speaker in the front, and the center of the two surround channel first speakers 33a and the second speaker 33b at the rear. Virtual image of surround channel sound can be perceived.
It is possible to obtain the surround effect by the channel sound.

[0004]

As shown in FIG. 3, when a plurality of speakers are arranged around a viewer so that a 4-channel surround sound is perceived by the viewer, a space for arranging the speakers is secured, and particularly, a listening operation is performed. It is essential to secure a space for arranging the speakers for the surround channels installed in the rear of the person.

The present invention solves the problem of securing a space for speaker placement, which is a problem when reproducing a surround sound signal having a multi-channel structure, and also realizes a sound field control capable of obtaining a sufficient sound field effect. An object is to provide an image display device with a device.

[0006]

The sound field control device of the present invention for solving the above problems is an imaginary method for locating a surround channel audio signal at a predetermined position with respect to a surround audio signal composed of multiple channels. Sound image generating means,
A surround-channel first speaker and a surround-channel second speaker for reproducing the surround-channel audio signal generated by the virtual sound image generating means; and a left-channel speaker for reproducing a left-channel audio signal.
A right channel speaker for reproducing the right channel audio signal, a center channel first speaker for reproducing the center channel audio signal, and a center channel second
A surround-speaker first speaker, a left-channel speaker, and a center-channel first speaker, which are arranged in this order from the front left upper part of the audience toward the bottom, and the surround-channel second speaker. A speaker, the speaker for the right channel, and the second speaker for the center channel are arranged at the same height as the speaker corresponding to each channel arranged on the front left side of the audience, in order from the front right side of the audience toward the bottom. The feature is that they are arranged.

[0007]

Since all the speakers for each channel are arranged in front of the viewer, the problem of securing a space for arranging the speakers can be solved, and a virtual sound image generating means is applied to the surround channel audio signal, which is equivalent to the conventional case. A sound field effect can be obtained.

[0008]

Embodiment 1 FIG. 1 is a block diagram showing the configuration of a video display device with a sound field control device according to Embodiment 1 of the present invention.

In FIG. 1, 1 is a MUSE decoder and 2 is the aforesaid
Surround channel audio signal output from MUSE decoder 1, 3 is left channel audio signal output from MUSE decoder 1, 4 is right channel audio signal output from MUSE decoder 1, 5 is output from MUSE decoder 1 Center channel audio signal, 6 is an arithmetic processing unit that performs virtual sound image generation processing on the surround channel audio signal 2, 7a is an A / D converter for inputting the surround channel audio signal 2 to the arithmetic processing unit 6. , 8 is a band-pass filter processing unit that receives the output from the A / D converter 7a as input, 9 is an output from the band-pass filter processing unit 8 that is input, and delays the same phase / sound pressure level. 2 is a delay processing unit that outputs two signals 10 and 11, 12 is a phase adjustment processing unit that receives the output signal 10 from the delay processing unit 9 and performs phase adjustment, and 7b is the phase adjustment processing unit 1 D / A converter that receives the output from 2 as input, 7c is a D that receives the signal 11 as input
A / A converter, 13 is a first amplification circuit for surround channel audio, which receives the signal output from the D / A converter 7b as an input,
Reference numeral 14 is a second amplifier circuit for surround channel audio which receives the signal output from the D / A converter 7c, 15 is an amplifier circuit for left channel audio which receives the left channel audio signal 3, and 16 is the right circuit A right channel audio amplifier circuit that receives the channel audio signal 4 as input, 17 is a center channel audio amplifier circuit that receives the center channel audio signal 5 as input, and 18a is the second surround channel audio signal
A surround channel first speaker driven by the amplifier circuit 14, 18b is a surround channel second speaker driven by the surround channel audio first amplifier circuit 14, and 19a is driven by the left channel audio amplifier circuit 15. Left channel speaker, 19
b is a right channel speaker driven by the right channel audio amplifying circuit 16, 20a is a first center channel speaker driven by the center channel audio amplifying circuit 17, and 20b is the center channel audio amplifying circuit 17 Is a second speaker for the center channel, 21 is a video display device of CRT, 22 is a video signal output from the MUSE decoder 1 and input to the video display device 21. Next, the operation of each part will be described.

The MUSE decoder 1 includes the surround channel audio signal 2, the left channel audio signal 3, the right channel audio signal 4, the center channel audio signal 5, and the video signal.
22 is output, and the video display device 21 inputs the video signal 21 and converts it into a video.

With respect to the surround channel signal output from the A / D converter 7a, in the arithmetic processing unit 6 which is the virtual sound image generating means for surround channel sound, a band having a center frequency of 2 kHz and having the characteristics shown in FIG. 2kHz, which is important for the viewer to perceive backwards with a pass filter
Highlight and select surrounding signals.

Next, the output from the bandpass filter 8 is input, and the delay processing unit 9 performs delay processing with an upper limit of 50 ms. As a result, the viewer perceives that these surround-channel speakers 18a, 18b are actually installed visually farther than the positions of the speakers 18a, 18b.

Further, one of two signals having the same phase and the same sound pressure level, which are separated by the delay processing section 9,
The phase adjustment processing unit 12 inverts the phase of the signal 10. When a viewer simultaneously listens to two signals, one of which is in the opposite phase of the other, the viewer easily perceives it as a sound with a spread and a sound image localized in the rear.

By the processing of the arithmetic processing unit 6 described above, the viewer actually installs the surround channel audio signal reproduced by the first surround channel speaker 18a and the second surround channel speaker 18b at the rear of the speaker. It can be perceived as a sound image equivalent to the conventional surround channel sound to be reproduced. The center channel sound is the first speaker 20a for the center channel,
By connecting the center channel second speaker 20b in series to the center channel audio amplifier circuit 17, signals of the same phase and the same sound pressure level are reproduced from both speakers, and the center channel first speaker 20a and the center channel first speaker 20a are reproduced. The virtual sound image localization of the center channel sound is performed in the center between the two speakers 20b.

Next, the effect of the speaker arrangement in the first embodiment on the virtual sound image localization of each channel will be described.

The virtual sound image of the center channel audio signal reproduced from the two center channel speakers installed at the bottom as shown in FIG. 1 is displayed as a video image on the video display device because of its priority over the visual sense of hearing. It is guided to the center of the department and pulled up. The most reproduced channel audio signal among the surround channel audio signal, the left channel audio signal, the right channel audio signal, and the center channel audio signal is the center channel audio signal that mainly contains the serif in a movie etc., and the surround channel audio signal. Since the audio signal is rarely strongly correlated with the displayed image, it is less likely to be given priority to the visual sense of hearing, and the viewer can see the surround channel audio signal relative to the virtual image localization of the center channel audio signal. Perceive a virtual sound image localization.

Further, since the sound image reproduced in the front upper part is easily perceived in the rear part, the virtual sound image of the center channel audio signal is raised by the display image and the virtual sound image of the surround channel audio signal is induced as described above. In the case of being raised, it becomes easier to perceive backward than the virtual sound image localization of the surround channel audio signal, which has just undergone the virtual sound image generation processing by the arithmetic processing unit 6 for rearward localization.

As described above, the surround channel speaker is arranged in the upper part and the center channel speaker is arranged in the lower part with the image display device sandwiched therebetween, and the arithmetic processing unit 6 reproduces the surround channel audio signal having the virtual sound image generating means. The viewer can easily perceive the surround channel audio signal further behind.

In the virtual sound image generating means for the surround channel, an equivalent circuit can be achieved by an analog circuit, and a head-related transfer function capable of sound image localization is found in the rear of the viewer and convolved with the surround channel audio signal. It is also possible to perform a calculation. Further, the same effect can be obtained when a Dolby Surround 4-channel audio signal is used instead of the 4-channel surround audio in the first embodiment.

In this embodiment, one speaker for each channel is arranged on the left and right, but the number of speakers of the present invention is not limited.

Further, in this embodiment, the vicinity of 2 KHz is taken as the center frequency of the surround channel sound, but the same effect can be obtained by extracting and reproducing the bands around 2 KHz and around 8 KHz.

[0022]

As described above, according to the present invention, by arranging the speakers of each channel in front of the viewer, the problem of securing a space for arranging the speakers is solved, and a surround sound equivalent to the conventional one is provided. A sound field reproduction effect can be achieved.

[Brief description of drawings]

FIG. 1 is a block diagram of a video display device with a sound field control device according to a first embodiment of the present invention.

FIG. 2 is a characteristic diagram of the bandpass filter in FIG.

FIG. 3 is a block diagram of a conventional surround sound reproducing device.

[Explanation of symbols]

 2 Surround channel audio signal 3 Left channel audio signal 4 Right channel audio signal 5 Center channel audio signal 6 Virtual sound image generation processing section for surround channel audio signal 13 to 17 Amplification circuit 18a, 18b, 19a, 19b, 20a, 20b Speaker 21 Video Display device

Claims (1)

[Claims] 1. A virtual sound image generating means for locating a surround channel audio signal at a predetermined position with respect to a surround audio signal composed of multiple channels, and a surround for reproducing the surround channel audio signal generated by the virtual sound image generating means. A first speaker for a channel, a second speaker for a surround channel, a left channel speaker for reproducing a left channel audio signal, a right channel speaker for reproducing a right channel audio signal, and a center channel for reproducing a center channel audio signal. First
A speaker for the center channel, a second speaker for the center channel, a first speaker for the surround channel, a speaker for the left channel, and a first for the center channel
Speakers are arranged in order from the upper left side to the lower side in front of the audience, and the second surround channel speaker, the right channel speaker, and the center channel second speaker are arranged on the front left side of the audience. An image display device with a sound field control device, which is arranged at the same height as a speaker corresponding to each channel, from the upper right side to the lower side in front of the audience.