JP2003169400A - Personal audio reproduction system - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a personal audio reproduction system which can produce an appropriate orientation of sound image stably with no individual difference. <P>SOLUTION: The personal audio reproduction system 20 for reproducing an audio signal S of 2 channel (Left ch, Right ch) stereophonically through speakers arranged in a chair 7 comprises a first set of speakers 3a and 3b arranged in the vicinity of the left and right feet lower than the armrest of the chair 7 and outputting the original signal sounds of the Left ch and Right ch of the audio signal amplified through a Left ch amplifier 11 and Right ch amplifier 12, respectively, and a second set of speakers 5a and 5b disposed in the vicinity of the left and right conchae 9 when a listener M sits in the chair 7 and outputting reproduced sound from the first set of speakers 3a and 3b after being collected and amplified by means of microphones MCL and MCR disposed at the left and right conchae 9' of a dummy head DH arranged in the chair 7. <P>COPYRIGHT: (C)2003,JPO

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a personal audio reproducing system, and more particularly to a personal audio reproducing system using a speaker arranged on a chair.

[0002]

2. Description of the Related Art A speaker is a stereo reproduction method for a general audio signal, in which a speaker is placed at the left and right, and further in the center with a certain distance in the direction of the reproduction sound, and the reproduction sound is heard. In a screen video / audio viewing system and the like, unless a sound screen is used, the front speaker is a hindrance to view the video, and especially the center speaker has a problem that it is difficult to place it.

Further, in order to construct a surround reproduction system for a home theater or the like, it is necessary to have a certain room size and a quantity, quantity and reproduction power corresponding to the number of channels such as a large speaker, a surround speaker and a large power amplifier. However, it is difficult to meet the above requirements when the room is small.

Therefore, in order to solve the above problem, speakers are attached to the left and right of the backrest of a chair such as an armchair at almost the height of the ears, and the reproduction sound of the stereo reproduction device is output and listened as it is. An audio playback system has also been devised. The personal audio playback system that uses this chair does not require a large-scale speaker or amplifier, and can be built with a small power audio playback system. There is.

However, in the case of the conventional personal audio reproducing system using the above-mentioned chair, since the audio signal of the stereo reproducing device is simply reproduced in stereo with the auricle, the reproduced sound can be heard from the rear or localized in the head. However, it is not possible to obtain a reproduced sound that gives a sense of distance and direction of the front localization equivalent to that when listening with a normal front speaker arrangement.

[0006]

Therefore, the inventor of the present application first uses a digital signal processor (abbreviated as DSP) to perform predetermined sound field processing (signal processing) so as to previously localize a forward sound image to an audio signal. I created a system that solves the above problems by playing with the auricle, but although there are significant improvements, there are individual differences in the sound image localization, and a stable and appropriate sense of distance and direction of the front localization is obtained. It is in a difficult situation to obtain.

Theoretically, the sound produced by the DSP can be reproduced by the left and right speakers arranged in the vicinity of the auricles of the listeners of the backrest, with a sound field having a sense of distance and direction equivalent to those heard with a normal speaker arrangement. It should be realized by performing signal processing based on the transfer function, but the accuracy that can be realized has not reached a satisfactory level in reality. In other words, it has not been sufficiently realized with a personal audio reproduction system to obtain a reproduced sound having a stable sense of distance and a sense of direction with forward localization that can be understood by any person regardless of who listens.

The present invention has been made in view of the above circumstances, and by causing two speaker sets arranged in separate parts of a chair to output audio signals of different conditions, there is no individual difference. The present invention provides a personal audio reproduction system capable of stably obtaining a proper sound image localization.

[0009]

The present invention provides: (1) A personal audio reproducing system for amplifying an audio signal S reproduced and output by a stereo reproducing device 1 and reproducing stereo by using speakers arranged on the left and right sides of a backrest of a chair. , A first speaker set 3a, 3b which is arranged below the armrests of the chair 7 near the left and right feet and which amplifies and outputs the original signal sound of the audio signal S.
And the left and right auricles 9 with the listener M sitting on the chair 7.
A microphone MCL disposed at a position near the microphone MCL disposed at the left and right auricles 9'of the dummy head DH in which the reproduced sound output from the first speaker set 3a, 3b is disposed inside the chair 7, A personal audio reproduction system 2 comprising: a second speaker set 5a, 5b that is picked up by the MCR, amplified, and output.
The above object is achieved by providing 0.

(2) In the personal audio reproducing system for amplifying the audio signal S reproduced and outputted by the stereo reproducing device 1 and reproducing stereo by the speakers arranged on the left and right of the back of the chair, in the left and right under the armrest of the chair 7. The audio signal S is provided near the foot.
The first speaker set 3a, 3b for amplifying and outputting the original signal sound and the second speaker arranged in the position near the auricles 9 on the left and right in the state where the listener M sits on the chair 7. Sets 5a and 5b, wherein the second speaker set is a multi-channel stereo speaker (2 channels of Left ch and Right ch) by a digital signal processor DSP.
For channels, Left ch, Center ch, Right ch, Surr
sound left ch, surround right ch 5 channels, etc.) The audio signal that has been subjected to the distribution signal processing to localize the sound image so as to be heard with a sense of distance and direction equivalent to the reproduction of the audio signal of each channel in the proper arrangement. The above problem is achieved by providing a personal audio reproduction system 10 characterized by amplifying and outputting S.

[0011]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Several embodiments of a personal audio reproducing system according to the present invention will be described with reference to the drawings.

FIG. 1 is a perspective view showing an example of a chair of a personal audio reproducing system of the present invention, FIG. 2 is a view showing an example of a usage state of the personal audio reproducing system of the present invention, and FIG. Is a diagram for explaining multi-channel signal processing by the DSP of the personal audio reproduction system according to claim 2, and FIG. 4 is a diagram for explaining the principle of signal processing for sound image localization of the personal audio reproduction system according to claim 2 of the present invention. 5 is a diagram for explaining the signal processing of the two-channel personal audio reproducing system according to claim 1 of the present invention, and FIG.
FIG. 6 is a diagram for explaining multi-channel signal processing of the personal audio reproduction system according to claims 1 and 2 of the present invention.

First, in the personal audio reproduction system 10 (see FIG. 3), 20 (see FIG. 5), and 30 (see FIG. 6) of the embodiment of the present invention, first, as a common component, As shown in FIG. 1 or FIG. 2, a second speaker attached to a position near the auricles of the left and right of the listener M sitting on the chair 7 (left and right of the backrest 7a of the chair 7 almost at the ear height). In addition to the sets 5a and 5b, the speaker system is configured such that the first speaker sets 3a and 3b are arranged near the left and right feet below the armrests 4a and 4b of the chair 7.

Secondly, the first speaker set 3a,
In 3b, the audio signal S of the stereo reproduction device 1 such as the DVD player of FIG. 2 has two channels (Left ch, Right c
In the case of h), the input signal (original signal sound) is L as it is.
It is amplified and reproduced by the ch amplifier 11 and the Rch amplifier 12 (see FIG. 5).

Further, the audio signal S is multi-channel (Left ch, Center ch, Right ch, Surround Left ch,
In the case of Surround Right ch), the signal of Center ch, which is attenuated by 3 dB in the reduction circuit 8 to the signal of Left ch, is added by the adder circuit 2.
Mix with 1 and amplify with Lch amplifier 11 to play,
Similarly, the signal of the center ch, which is attenuated by 3 dB to the signal of the right ch, is mixed by the adder circuit 22, amplified by the Rch amplifier 12, and reproduced (see FIG. 3 or 6). Both are first
With respect to the reproduction outputs of the speaker sets 3a and 3b, the sound field processing for sound image localization is not performed and the original signal sound is output.

Next, in the two-channel personal audio reproducing system 20 of FIG. 5 according to claim 1 of the present invention, the backrest 7a of the chair 7 is installed in the vicinity of the left and right auricles at approximately the ear height. In the speaker sets 5a and 5b, the reproduced output sounds of the first speaker sets 3a and 3b are arranged at the positions of the left and right auricles 9'of the dummy head DH arranged inside the chair 7 (for example, in the lower center of the seat surface). Microphone M installed
Sounds are collected by CL and MCR, and Lch amplifier 11 and Rch respectively
The signal amplified by the amplifier 12 is output.

In the case of the multi-channel personal audio reproducing system 30 shown in FIG.
Left rear localization processing (described later) and Surround Right for t ch signal
In addition to a signal obtained by performing right rearward localization processing (to be described later) on the ch signal by the microphones MCL and MCR arranged at the positions of the left and right auricles 9'of the dummy head DH, Lch amplifier 11 and Rch It is amplified by the amplifier 12 and output from the second speaker set 5a, 5b.

Next, in the case of the multi-channel personal audio reproducing system 10 of FIG. 3 according to claim 2 of the present invention, the microphones MCL and MCR of the dummy head DH are used.
Signal processing similar to sound image localization by means of sound pickup by DS
P is used to output by the second speaker set 5a, 5b.

The function of each function shown in FIG. 3 will now be described. For example, a "left front localization function" means that a left ch input signal of the audio signal S is processed by the characteristic of this function to listen. The listener M hears the speaker LSP as if the speaker LSP is located at the proper left ch speaker location in front of the person M. The right front localization function, the left rear localization function, ... Have similar functions.

Next, the characteristics of each of the above functions will be described below by taking the "left front localization function" as an example. The right front localization function, the left rear localization function, ... Can be obtained in the same manner. In FIG. 4, the acoustic transfer function of the sound emitted from the left front speaker LSP of the listener M until it reaches the vicinity of the left and right auricles 9 including the reflected sound and the reverberant sound of the space, respectively. L), acoustic transfer function (R)
And These functions place a microphone near the pinna 9,
By reproducing a predetermined signal from the speaker LSP,
It can be determined by measurement. (It can also be obtained by theoretical calculation.) Obtained transfer functions (L) and (R)
Since the characteristic of can be realized by the DSP, the input signal of each channel of the audio signal S can be processed by the DSP. After all, the content of "Left front localization function" is
This means that the input signal of each channel is distributed to two systems of Lch and Rch by the acoustic transfer function (L) and the acoustic transfer function (R).

Next, the signal processing and reproduction characteristics by each of the above functions will be described. The Left ch input signal in FIG. 3 is processed by the characteristics of the above acoustic transfer function (L) to obtain L ch.
In addition to being reproduced from the speaker 5a, processed by the characteristic of the acoustic transfer function (L) and reproduced from the Rch speaker 5b, the Lch and Rch speakers 5a and 5b placed near the auricle of the listener have both auricles. Since the same sound field as that at the time of measurement is created in the vicinity of 9, the speakers 5a and 5b are in the vicinity of the auricle behind the listener M as shown in FIG.
The reproduced sound of ft ch is perceived as coming from the front left.

Although this is processing by the left front localization function, input signals of other channels can be processed in the same manner. However, the center ch is attenuated by 3 dB and mixed into the left and right signals by the adders 21 and 22 to be treated as the left and right signals. However, when this is reproduced, the left and right signals have the same level and the same phase. Cent as in stereo playback
It goes without saying that the er ch sound can be heard from the front side of the front of the listener M.

In the personal audio reproducing system 10, 20, 30 described above, the first speaker set 3 is used.
a, 3b and the level ratio of the reproduced sound of the second speaker set 5a, 5b depending on the shape and internal structure of the chair 7, the arrangement of the first speaker set 3a, 3b and the second speaker set 5a, 5b. Reproduction is performed at a predetermined ratio.

As a result of an experiment conducted by the present inventor, in addition to the second speaker sets 5a and 5b located near the auricles 9, the first speaker sets 3a and 3b are used as the original signal sound reproducing speakers of the audio signal. With the addition, it has become possible to make the proper sound image localization more stable and reliable by the synergistic effect of both speaker sets. That is, as shown in FIG. 3, FIG. 5 and FIG.
(Left ch), 42 (Right ch), 45 (Center ch),
43 (Surround Left ch), 44 (Surround Right c)
Most people are now able to perceive the sound source of each channel at the proper position in h). A conventional 2ch stereo audio signal is reproduced in the front, and a 5-channel audio signal S of a stereo reproduction device 1 such as a DVD player in a large screen image viewing system having a screen 31 as shown in FIG. You can

Although the above embodiment is a case of a stool, the personal audio reproducing system of the present invention can be applied to a chair if considering the use between Japan. Of course. Further, it goes without saying that the present invention can be applied to a pilot's seat or the like even for a game machine in which sound movement and sound source position are particularly important.

[0026]

Since the personal audio reproducing system according to the present invention is configured as described above, (1) a sense of distance and direction equivalent to those reproduced with a conventional speaker arrangement can be stably obtained without individual differences. Realization of a personal audio reproduction system that provides a sound image localization with a sense of feeling. (2) The large-screen video viewing system does not require a front speaker or a surround speaker, so that the system can be constructed without disturbing the large screen. (3) In a large-screen video viewing system or audio system, since it is basically near-field listening, there is no need for specially acoustically processed rooms, no large speakers, no large power amplifiers, and space saving. is there.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a chair of a personal audio reproducing system of the present invention.

FIG. 2 is a diagram showing an example of a usage state of the personal audio reproduction system of the present invention.

FIG. 3 is a diagram illustrating multi-channel signal processing by the DSP of the personal audio reproduction system according to claim 2 of the present invention.

FIG. 4 is a diagram illustrating the principle of signal processing for sound image localization in the personal audio reproduction system according to claim 2 of the present invention.

FIG. 5 is a diagram illustrating signal processing of a 2-channel personal audio reproduction system according to claim 1 of the present invention.

FIG. 6 is a diagram illustrating multi-channel signal processing of the personal audio reproduction system according to claim 1 and claim 2 of the present invention.

[Explanation of symbols]

1 Stereo Playback Device (DVD Player etc.) 3a, 3b First Speaker Set 4a, 4b Armrest 5a, 5b Second Speaker Set 7 Chair 7a Backrest 8 Attenuator 9, 9'Auricle 10, 20, 30 Personal Audio Playback System 11, 13 Left ch amplifier 12, 14 Right ch amplifier 21, 22, 23, 24 Adder 31 Large screen 41 to 45 Virtual speaker for sound localization MCL Left microphone MCR Right microphone M Listener DH Dummy head

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Claims (2)

[Claims] 1. A personal audio reproducing system for amplifying an audio signal reproduced and output by a stereo reproducing device and reproducing stereo by using speakers arranged on the left and right sides of a backrest of a chair. A first speaker set that is provided and outputs the original signal sound of the audio signal after being amplified; and a first speaker set that is disposed near the auricles on the left and right when the listener sits on the chair and the first speaker set. A second speaker set in which reproduced sound output from the first speaker set is picked up by a microphone arranged in the left and right auricle positions of a dummy head arranged inside the chair, amplified, and output. Personal audio playback system characterized by. 2. A personal audio reproducing system for amplifying an audio signal reproduced and output by a stereo reproducing device and reproducing stereo by using speakers arranged on the left and right sides of a backrest of a chair. A first speaker set that is provided and outputs the original signal sound of the audio signal after being amplified, and a second speaker set that is disposed in a position corresponding to the left and right auricles in a state where a listener sits in the chair. A speaker set, and the second
Of the speaker set is amplified by the digital signal processor, which has been subjected to the distribution signal processing to localize the sound image so that it can be heard with a sense of distance and direction equivalent to the reproduction of the audio signal of each channel in the proper arrangement of the multi-channel stereo speakers. A personal audio reproduction system characterized by outputting as.