JP2007028046A - Multi-channel audio system and its voice-level adjusting method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To improve the versatility of a multi-channel audio system, and to continue an optimum sound-field reproduction, even when a listening point is displaced in the multi-channel audio system in a three channel type or the like. <P>SOLUTION: Distances among each loudspeaker (5A, 5B and 5C) and a remote controller 3 are measured at every fixed time, and the voice levels of each loudspeaker 5 are adjusted in response to the distances. Accordingly, the voice levels are adjusted regardless of the places of the loudspeakers 5 installed regarding each loudspeaker 5, and an optimum sound field is reproduced even when the states of the installations of the loudspeakers 5 are not proper. The listening point can be monitored at all times. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a multi-channel audio system of various channel systems such as a 3-channel system, a 4-channel system, a 5.1 channel system, and a 7.1 channel system.

In this type of multi-channel audio system, several methods for performing high-quality sound field reproduction have been proposed. For example, as disclosed in Patent Document 1, there is a method (hereinafter referred to as “known technique 1”) that detects the position of a viewer using an infrared sensor and performs optimum sound field reproduction for the viewer. . Further, as disclosed in Patent Document 2, the three-dimensional coordinates of each speaker are estimated based on the propagation delay time between the speakers, and the delay time and reproduction level of each channel are controlled based on the three-dimensional coordinates. By doing so, there is also a technique (hereinafter referred to as known technique 2) for realizing an optimal sound field reproduction.
Japanese Utility Model Publication No. 5-53400 JP 2003-250200 A

  However, these methods have the following disadvantages.

  First, in the known technique 1, since it is necessary to assume that the speaker is properly installed in order to perform optimum sound field reproduction, the versatility of the multi-channel audio system is low.

  On the other hand, in the known technique 2, when the viewer moves, the listening point shifts, and the optimum sound field reproduction cannot be continued.

  It is an object of the present invention to provide a multi-channel audio system and a method for adjusting the sound level thereof that can eliminate such disadvantages.

First, the invention of the multi-channel audio system according to claim 1 is a multi-channel audio system in which a device main body outputs sound from a plurality of speakers based on an operation of the remote controller, and the distance from each speaker to the remote controller Distance measuring means for measuring the sound level and sound level adjusting means for adjusting the sound level of each speaker according to the distance.
The invention of the multi-channel audio system according to claim 2 is characterized in that the distance measuring means measures a distance from each speaker to the remote controller at predetermined time intervals.
According to a third aspect of the present invention, there is provided a multi-channel audio system according to the present invention, wherein the distance measuring means is input from the remote controller to each speaker based on the arrival time of an audio reproduction command signal input from the remote controller to the device body. The input delay time of the received signal is obtained, and the distance from the speaker to the remote controller is measured based on the input delay time.
According to a fourth aspect of the present invention, there is provided a warning means for issuing a warning when the signal is not input to the speaker.
Further, the invention of the multi-channel audio system according to claim 5 is characterized in that the sound level adjusting means equalizes the sound level at the location of the remote controller with each speaker.
The invention of a sound level adjusting method for a multi-channel audio system according to claim 6 is a sound level adjusting method for a multi-channel audio system in which a device body outputs sound from a plurality of speakers based on an operation of a remote controller. And a distance measuring step for measuring a distance from each speaker to the remote controller, and a sound level adjusting step for adjusting a sound level of each speaker according to the distance.
According to a seventh aspect of the present invention, there is provided an audio level adjusting method for a multi-channel audio system, wherein in the distance measuring step, a distance from each speaker to the remote controller is measured every predetermined time.
The audio level adjusting method of the multi-channel audio system according to claim 8 is characterized in that, in the distance measuring step, the remote control is based on the arrival time of the audio reproduction command signal input from the remote controller to the device body. The input delay time of the signal input to each speaker is obtained, and the distance from the speaker to the remote controller is measured based on the input delay time.
According to a ninth aspect of the present invention, there is provided an audio level adjustment method for a multi-channel audio system, further comprising a warning step in which a warning is issued when the signal is not input to the speaker.
According to a tenth aspect of the present invention, there is provided an audio level adjustment method for a multi-channel audio system, wherein in the audio level adjustment step, an audio level at a location of the remote controller is equalized by each speaker.

  According to the present invention, since the sound level of each speaker is adjusted regardless of the installation position, optimum sound field reproduction is performed even if the speaker installation state is not appropriate. Therefore, the versatility of the multichannel audio system can be improved.

  In addition, by measuring the distance between each speaker and the remote controller every predetermined time, the location of the remote controller, that is, the listening point can be constantly monitored. As a result, even if the listening point shifts with the movement of the viewer, it is possible to continue the optimal sound field reproduction.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings.

  FIG. 1 is a layout diagram showing an embodiment of a multi-channel audio system according to the present invention, FIG. 2 is a control block diagram of a remote controller, FIG. 3 is a schematic diagram showing a method for calculating a distance from a speaker to the remote controller, and FIG. FIG. 5 is a layout view showing another embodiment of a multi-channel audio system according to the invention.

  As shown in FIG. 1, the multi-channel audio system 1 includes a device main body 2 installed indoors, a remote control 3 for remotely operating the device main body 2, and a front connected to the device main body 2 in a wired or wireless manner. Three-channel speakers 5 (Center speaker 5A, Lch speaker 5B, Rch speaker 5C) are provided.

  As shown in FIG. 2, the device main body 2 has a main control unit 21 such as a CPU (Central Processing Unit). The main control unit 21 includes a light receiving unit 22, a distance measuring unit 23, an audio. A level adjustment unit 24 and a warning unit 25 are connected.

  Further, as shown in FIG. 1, a light receiving unit 51 that receives a signal from the remote controller 3 is attached to the front surface of each speaker 5.

  Since the multi-channel audio system 1 has the above-described configuration, when listening to music using the multi-channel audio system 1, the viewer appropriately operates the operation keys of the remote controller 3 to make the device main body 2 Output a voice playback command signal. Then, the device main body 2 receives this sound reproduction command signal via the light receiving unit 22 and outputs sound from the three speakers 5. At this time, the remote controller 3 outputs a sound reproduction command signal to the device body 2 and simultaneously outputs a signal to the light receiving unit 51 of each speaker 5.

  Here, the apparatus body 2 adjusts the sound level of each speaker 5 in accordance with the location where the viewer is present, that is, the listening point, as described below, in order to realize the optimum sound field reproduction. Here, the location of the remote controller 3 is regarded as a listening point.

  First, the main control unit 21 of the device main body 2 instructs the distance measurement unit 23 to measure the distance from each speaker 5 to the remote controller 3. In response to this, the distance measuring unit 23 measures the distance from each speaker 5 to the remote controller 3 every predetermined time (for example, 1 minute, 5 minutes, etc.). For this purpose, the distance measuring unit 23 obtains the input delay time of the signal input from the remote controller 3 to each speaker 5 with reference to the time when the audio reproduction command signal input from the remote controller 3 to the device body 2 arrives. Based on the delay time, the distance from each speaker 5 to the remote controller 3 is calculated.

For example, as shown in FIG. 3, two-dimensional orthogonal coordinates (x, y) are introduced into a plane including each speaker 5 and the remote controller 3, and the center speaker 5A is set as the origin (0, 0). Here, if the coordinates of the Lch speaker 5B are (X _L , 0), the coordinates of the Rch speaker 5C are (X _R , 0), and the coordinates of the listening point are (X, Y), X and Y are It is represented by the mathematical formula shown.

  Then, the distance r from the center speaker 5A to the remote controller 3 is expressed by the mathematical expression shown in Formula 2 by the three square theorem.

  Further, the distance (r + a) from the Lch speaker 5B to the remote controller 3 is expressed by the mathematical formula shown in Equation 3 according to the three-square theorem.

  Further, the distance (r + b) from the Rch speaker 5C to the remote controller 3 is expressed by the mathematical formula shown in Equation 4 according to the three-square theorem.

  Next, the main control unit 21 of the device main body 2 instructs the audio level adjustment unit 24 to adjust the audio level of each speaker 5. In response to this, the audio level adjustment unit 24 adjusts the audio level of each speaker 5 to be uniform at the listening point according to the distance between each speaker 5 and the remote controller 3. That is, based on the idea that the sound level output from the speaker 5 attenuates in inverse proportion to the distance to the listening point, the sound level of each speaker 5 is controlled to increase or decrease in proportion to the distance from the remote controller 3. The Therefore, even if the distance between each speaker 5 and the remote controller 3 is various, it is possible to realize optimum sound field reproduction.

For example, the voice output from the Center speaker. 5A and the attenuation of the sound level to reach the L ch speaker 5B phi, attenuation per unit length becomes φ / X _L. Therefore, the optimum audio level output from the center speaker 5A at the listening point is equal to the audio level before optimization plus attenuation (φ / X _L ) × r. Similarly, the optimal audio level output from the Lch speaker 5B at the listening point is equal to the audio level before optimization plus attenuation (φ / X _L ) × (r + a). Further, the optimum audio level output from the Rch speaker 5C at the listening point is equal to the audio level before optimization plus attenuation (φ / X _L ) × (r + b).

  As described above, since the sound level of each speaker 5 is adjusted regardless of the installation position, optimum sound field reproduction is performed even if the installation state of the speaker 5 is not appropriate. Therefore, the versatility of the multichannel audio system 1 can be improved.

  Further, by measuring the distance between each speaker 5 and the remote controller 3 every predetermined time, the location of the remote controller 3, that is, the listening point can be constantly monitored. As a result, even if the listening point shifts with the movement of the viewer, it is possible to continue the optimal sound field reproduction.

  If the position of the speaker 5 is extremely inappropriate, a response signal from the speaker 5 may not be input to the remote controller 3. In this case, since the distance between the speaker 5 and the remote controller 3 cannot be measured accurately, the distance measuring unit 23 instructs the warning unit 25 to issue a warning. In response to this, the warning unit 25 issues a warning to the listener by sounding a warning sound from the speaker 5. Then, since the viewer knows that the measurement of the distance between the speaker 5 and the remote controller 3 and thus the sound level adjustment has failed, it is possible to take appropriate measures such as changing the position and orientation of the speaker 5. Therefore, the usability of the multi-channel audio system 1 is improved.

  In the above-described embodiment, the three-channel multi-channel audio system 1 has been described. However, the channel method is not limited to this. For example, as shown in FIG. 4, the present invention can be applied to a 5.1 channel multi-channel audio system 1. Further, the present invention can be applied to a multi-channel audio system 1 of a system other than these (for example, 4-channel system, 7.1-channel system, etc.).

  The present invention can be widely applied to home theaters and the like.

1 is a layout view showing an embodiment of a multi-channel audio system according to the present invention. It is a control block diagram of an apparatus main body. It is a schematic diagram which shows the calculation method of the distance from a speaker to a remote control. FIG. 6 is a layout view showing another embodiment of a multi-channel audio system according to the present invention.

Explanation of symbols

1 …… Multi-channel audio system 2 …… Device body 3 …… Remote control 5 …… Speaker 33 …… Distance measuring unit (distance measuring means)
34 …… Sound level adjustment unit (sound level adjustment means)
35 …… Warning part (Warning means)

Claims (10)

A multi-channel audio system in which the device body outputs sound from multiple speakers based on the operation of the remote control,
Ranging means for measuring the distance from each speaker to the remote control;
And a sound level adjusting means for adjusting a sound level of each speaker according to the distance. The distance measuring means includes
The multi-channel audio system according to claim 1, wherein a distance from each of the speakers to the remote controller is measured every predetermined time. The distance measuring means includes
Based on the arrival time of the audio reproduction command signal input from the remote control to the device body, the input delay time of the signal input from the remote control to each speaker is obtained, and based on this input delay time, the speaker The multi-channel audio system according to claim 1 or 2, wherein a distance to the remote control is measured.   4. The multi-channel audio system according to claim 3, further comprising warning means for issuing a warning when the signal is not input to the speaker. The sound level adjusting means is
The multi-channel audio system according to any one of claims 1 to 4, wherein a sound level at a location of the remote controller is equalized by each speaker. An audio level adjustment method for a multi-channel audio system in which a device body outputs audio from a plurality of speakers based on an operation of a remote control,
A distance measuring step for measuring a distance from each speaker to the remote control;
And a sound level adjustment step of adjusting a sound level of each speaker according to the distance. A sound level adjustment method for a multi-channel audio system. In the distance measuring step,
The method for adjusting the sound level of a multi-channel audio system according to claim 6, wherein the distance from each speaker to the remote controller is measured every predetermined time. In the distance measuring step,
Based on the arrival time of the audio playback command signal input from the remote control to the device main body, the input delay time of the signal input from the remote control to each speaker is obtained, and based on this input delay time, from the speaker The method for adjusting the sound level of a multi-channel audio system according to claim 6 or 7, wherein a distance to the remote controller is measured.   The method of claim 8, further comprising a warning step in which a warning is issued when the signal is not input to the speaker. In the audio level adjustment step,
10. The audio level adjustment method for a multi-channel audio system according to claim 6, wherein an audio level at a location of the remote control is made uniform by each speaker.