JP2006254497A - Acoustic processing apparatus and acoustic processing method - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To reproduce a sound close to an original sound at a position of a listener by branching an acoustic signal of at least one channel, among acoustic signals of three or more channels produced from a reproduction signal from an acoustic source, to create a branch signal and adding the branch signal to the acoustic signals of the other channels. <P>SOLUTION: In the acoustic processing apparatus, at least one of at least three acoustic signals produced by an acoustic signal producing means using a reproduction signal from an acoustic source is branched in a branching step to extract a branch signal, and the extracted branch signal is added to the acoustic signals, other than the acoustic signal branched in the branching step, in an adding step. Based on a distance between a reproduction position of the acoustic signal from which the branch signal is extracted in the branching step and a reproduction position of the acoustic signal to which the branch signal is added in the adding step, the branch signal is delayed in a processing step, and a level of the branch signal is controlled. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to an acoustic processing apparatus and an acoustic processing method, and more particularly, from a multi-channel playback apparatus capable of reproducing a multi-channel recording type music source such as a DVD (Digital Multipurpose Disc) player, The present invention relates to an improvement in an acoustic effect in an acoustic processing apparatus and an acoustic processing method that transmit independent acoustic signals to speakers.

  2. Description of the Related Art Conventionally, an audio device for enjoying music in a passenger compartment is provided in a vehicle such as an automobile. In the early days of the audio device provided in the vehicle interior, a simple two-channel stereo in which two speakers were provided on the left and right sides of the vehicle was the mainstream. However, in order to listen to music with better sound in the vehicle interior, vehicle interior acoustic systems with an increased number of speakers installed in the vehicle interior have become widespread.

  As an example of the arrangement of the speakers in the vehicle interior acoustic system provided with such a large number of speakers, there is one provided with six speakers. The breakdown of the six speakers is, for example, a center speaker installed in the center of the front of the vehicle interior, a left front speaker and a right front speaker installed on the left and right of the vehicle interior, and left and right of the vehicle interior. A left rear speaker, a right rear speaker, and a bass dedicated speaker. As an advanced type of these six speakers, there is a type in which a tweeter (high-frequency dedicated speaker) is added to each of the left and right front speakers. In such an acoustic system, sound reproduced from each speaker is reproduced by applying frequency correction processing and reverberation processing to the sound distributed to the left and right channels. At that time, for example, the sound that can be heard by a person in the backseat has an acoustic effect mainly by the sound output from the rear speaker.

  On the other hand, in recent years, multi-channel audio in which the number of channels of music sources is increased is becoming widespread in place of conventional two-channel music sources such as audio cassettes and CDs. As an example of this multi-channel audio, there is a DVD adopting an independent 6-channel or 8-channel digital surround system.

  In the DVD digital surround system, music sources are played back from six speakers arranged in the room, and the music sources are recorded on the disc by an independent multi-channel recording system for each of the six speakers. Yes. The six speakers in the DVD are a center speaker, a left front speaker, a right front speaker, a left rear speaker, a right rear speaker, and a bass dedicated speaker (woofer), respectively. Among these, the sound reproduced from the woofer is, for example, a low sound of 120 Hz or less, and the information amount is small compared to the information amount of other channels to be reproduced up to 20 kHz. It is called a channel.

  By the way, when the above-mentioned six speakers are mounted on an automobile, in the conventional two-channel stereo, for example, when an occupant (listener) sits on the rear right seat, playback is performed from the right front speaker and the right rear speaker. The sound played is basically the same. Therefore, when the same sound is reproduced from the right front speaker and the right rear speaker, the sound heard by the listener sitting on the rear right seat is dominated by the right rear speaker.

  On the other hand, when the 5.1 channel sound is reproduced from these six speakers, the sound of the six channels is recorded on the recording medium independently, so the sound reproduced from the woofer is excluded. The sound reproduced from the other five speakers can be freely controlled. For example, if the same sound is reproduced from five speakers with a predetermined delay time, the sound can be turned around the listener.

  However, considering the case of playing a music source that sounds around the listener as described above, the sound coming from the left front speaker for the listener sitting on the rear right seat is Because the sound pressure is low and the high sound is attenuated because the sound is far away, the sound coming from the right rear speaker is a sound with a large sound pressure and a wide band. There was a problem that it was heard as a different sound.

  This is because when a source with high independence between channels, such as a multi-channel source, is played by multiple speakers, the sound played from a speaker far from the listening position and the sound played from a near speaker are played. This is because the difference between pressure and frequency characteristics becomes a problem. For example, if the sound played by the front speaker and the rear speaker mounted on the vehicle is different, the person in the backseat hears the sound coming from the front side different from the sound coming from the rear side, with the sound coming from the front side This is because the sound has a lower sound pressure than the sound coming from the rear side, and there is a tendency for the frequency characteristics to deteriorate, particularly the attenuation in the high range.

  Therefore, the present invention provides a listening position of a listener who listens to sound reproduced from each speaker when a medium on which a multi-channel source is recorded is reproduced from speakers installed at the same number of channels. Accordingly, the signal reproduced from the medium reproducing device is processed on the amplifier unit side arranged in front of each speaker, so that the sound close to the original sound recorded on the medium can be reproduced at the position of the listener. An object is to provide an acoustic processing apparatus and an acoustic processing method.

  The acoustic processing apparatus of the present invention that achieves the above object generates at least three acoustic signals from a reproduction signal from an acoustic source and outputs them, and at least one of acoustic signals from the acoustic signal generating means. A branch stage for branching out two acoustic signals and extracting the branch signal, an addition stage for adding the branch signal from the branch stage to an acoustic signal other than the one branched at the branch stage, and the sound from which the branch signal is extracted at the branch stage And a processing stage for delaying the branch signal and adjusting the level of the branch signal based on the distance between the reproduction position of the signal and the reproduction position of the acoustic signal to which the branch signal is added in the addition stage. The sound processing device.

  The acoustic processing method of the present invention that achieves the above object generates at least three acoustic signals from a reproduction signal from an acoustic source, branches at least one of the acoustic signals, extracts a branched signal, and extracts the branched signal. Is added to the sound signal other than the branched signal, and the branched signal is delayed based on the distance between the reproduction position of the acoustic signal from which the branched signal is extracted and the reproduction position of the acoustic signal to which the branched signal is added. In addition, the sound processing method is characterized in that a processed sound is generated by adjusting a level of the branch signal.

  According to the present invention, when a medium on which a multi-channel source is recorded is reproduced from speakers installed at the same number of locations as the number of channels, the listening position of the listener who listens to the sound reproduced from each speaker is obtained. Accordingly, the sound signal reproduced from the medium reproducing device is processed on the amplifier unit side arranged in front of each speaker, so that the sound close to the original sound recorded on the medium can be heard at the listener's position. Can do.

Embodiments of the present invention will be described below in detail based on specific examples with reference to the accompanying drawings.
FIG. 1 is a perspective view showing installation positions of a plurality of speakers in an automobile 9 equipped with a sound processing apparatus to which the present invention is applied. In the figure, 10 is an audio unit installed on the instrument panel of the automobile 9, CE is a center speaker arranged at the center of the upper surface of the instrument panel of the automobile, and FL is a left installed below the left front door. Front speaker, FR is a right front speaker installed at the lower part of the right front door, RL is a left rear speaker installed at the lower part of the left rear door, RR is a right rear speaker installed at the lower part of the right rear door, WF Is a low-frequency speaker woofer installed on the rear shelf. In this embodiment, the audio unit 10 is provided with a DVD player as a multi-channel playback device. The 6-channel signal reproduced by the DVD player is demodulated, corrected, and amplified by the audio unit 10 and output to each speaker.

  FIG. 2 explains the configuration of the sound processing apparatus according to the present invention, and shows the connection between the audio unit 10 of FIG. 1 and each speaker. The audio unit 10 includes a DVD player 1 which is a multi-channel playback device and an amplifier unit 2. The amplifier unit 2 includes a center speaker CE, left and right front speakers FL and FR, left and right rear speakers RL and RR, and a woofer WF. Is connected. From the DVD player 1, reproduced stream signals (digital signals) for six channels are input to the amplifier unit 2.

  The amplifier unit 2 includes a receiving circuit (DIR: Digital Interface Receiver) 3, a DSP (Digital Signal Processor) 4, and amplifiers 11 to 16 for driving each speaker. The DSP 4 is provided with a decoder 5, a matrix delay addition processing circuit 6, and an equalizer 7. The equalizer 7 is a general-purpose equalizer such as a graphic equalizer or a parametric equalizer. The stream signal input from the DVD player 1 to the amplifier unit 2 is received by the DIR 3 and then input to the decoder 5. The decoder 5 decodes the stream signal and converts it into a center speaker signal SCE, left and right front speaker signals SFL and SFR, left and right rear speaker signals SRL and SRR, and a woofer signal SWF.

  The converted signal for each speaker is subjected to delay processing and addition processing, which will be described later, in the matrix delay addition processing circuit 6, and then the sound quality is adjusted by the equalizer 7 to drive the speakers 11 to 16. Entered. The amplifier 11 is for driving the center speaker CE, the amplifier 12 is for driving the left front speaker FL, the amplifier 13 is for driving the right front speaker FR, the amplifier 14 is for driving the left rear speaker RL, and the amplifier 15 is the right rear speaker RR. The amplifier 16 is used for driving the woofer.

Next, details of the delay processing and addition processing of the drive signals of each speaker in the matrix delay addition processing circuit 6 according to the present invention will be described based on several embodiments.
FIG. 3 is a block circuit diagram showing the configuration of the first embodiment of the matrix delay addition processing circuit 6 of FIG. 3 indicates an input signal to the matrix delay addition processing circuit 6 in FIG. A plurality of signal processing circuits 20 are provided in the matrix delay addition processing circuit 6. The signal processing circuit 20 is configured by connecting an equalizer 21, a delay circuit 22, and an amplifier 23 in series. Reference numerals d1 to d3 described in the delay circuit 22 indicate a delay time. ing.

  As shown in FIG. 5 (a), the delay times d1 and d2 are the time until the sound output from the center speaker CE reaches the left and right rear speakers RL and RR, or the sound output from the rear speakers RL and RR, respectively. Is the time until each reaches the center speaker CE. The delay times d3 and d4 are the time required for the sound from the left and right front speakers FL and FR to reach the opposite right and left rear speakers RR and RL, or the sound from the right and left rear speakers RR and RL, respectively. Is the time required to reach the left and right front speakers FL, FR facing each other. Further, the delay times d5 and d6 are the time until the sound output from the left and right front speakers FL and FR reaches the adjacent left and right rear speakers RL and RR, or the sound output from the left and right rear speakers RL and RR, respectively. Is the time required to reach the adjacent left and right front speakers FL, FR. Therefore, here, (d1≈d2)> (d3≈d4)> (d5≈d6).

  In the first embodiment, as shown in FIG. 3, the signal SCE to the center speaker CE is branched, and after the frequency characteristic is adjusted by the equalizer 21 of the signal processing circuit 20, it is delayed by the time d2 by the delay circuit 22. After the gain is adjusted in the attenuation direction by the amplifier 23, it is added to the signal SRR to the right rear speaker RR. Further, the signal SFL to the left front speaker FL is branched, the frequency characteristic is adjusted by the equalizer 21 of the signal processing circuit 20, and then delayed by the time d3 by the delay circuit 22, and the gain is adjusted by the amplifier 23 in the attenuation direction. Is added to the signal SRR to the right rear speaker RR. Further, the signal SFR to the right front speaker FR is branched, the frequency characteristic is adjusted by the equalizer 21 of the signal processing circuit 20, and then delayed by the time d6 by the delay circuit 22, and the gain is adjusted by the amplifier 23 in the attenuation direction. Is added to the signal SRR to the right rear speaker RR.

  Similarly, the signal SCE to the center speaker CE is branched by the signal processing circuit 20 and is added to the signal SRL to the left rear speaker RL after adjusting the frequency characteristics, delaying the delay time d1, and adjusting the gain. The signal SFL to the left front speaker FL is branched by the signal processing circuit 20 and is added to the signal SRL to the left rear speaker RL after adjusting the frequency characteristics, delaying the delay time d5, and adjusting the gain. Further, the signal SFR to the right front speaker FR is branched by the signal processing circuit 20 and is added to the signal SRL to the left rear speaker RL after adjusting the frequency characteristic, delaying the delay time d4, and adjusting the gain.

  Conversely, the signal SRL to the left rear speaker RL is branched by the three signal processing circuits 20, and the signal SCE to the center speaker CE is subjected to frequency characteristic adjustment, delay time d1 delay, and gain adjustment. The frequency characteristics, delay time d4, and gain adjustment are added to the signal SFR to the right front speaker FR, and the frequency characteristics are adjusted, the delay time d5 is delayed, and the gain is adjusted. Is added to the signal SFL to the left front speaker FL. Similarly, the signal SRR to the right rear speaker RR is branched by the three signal processing circuits 20, and the signal SCE to the center speaker CE is subjected to frequency characteristic adjustment, delay time d2 delay and gain adjustment. The frequency characteristics, delay time d3, and gain adjustment are added to the signal SFL to the left front speaker FL, and the frequency characteristics are adjusted, the delay time d6 is delayed, and the gain is adjusted. Is added to the signal SFR to the right front speaker FR.

When the center speaker CE is on the center line of the vehicle, d1 = d2, d3 = d4, and d5 = d6.
As described above, in the first embodiment, the sound output from the center speaker CE is delayed and attenuated after the frequency characteristics are adjusted, and added to the sound output from the left and right rear speakers RL and RR. The sound output from the front speakers FL and FR is delayed and attenuated after the frequency characteristics are adjusted and added to the sound output from the left and right rear speakers RL and RR, and is output from the left and right rear speakers RL and RR. After the frequency characteristics are adjusted, the sound is delayed and attenuated and added to the left and right front speakers FL and FR and the center speaker CE and output. The signal SWF to the woofer WF is output without being processed. This is because the sound coming out of the woofer has a very low frequency, so it can be heard in any seat in the passenger compartment. This is also because it is difficult to reproduce the woofer sound band with other speakers.

  Here, the attenuation characteristic of the amplifier 23 in each signal processing circuit 20 will be described with reference to FIGS. Regarding sound, the first wavefront law (also called the Haas effect in the name of the inventor), in which the direction of the sound wave that first arrives at the listener's position, has a dominant influence on the auditory perception of sound image localization. Are known. According to this law, the reflected sound comes from various directions in the room following the sound wave that reaches the listener directly from the sound source, but the listener hears that the sound source is in the direction of the direct sound. . Loudspeakers such as performance halls are designed based on this law. That is, for example, when the volume from the front speaker of a singer singing on the stage is at a predetermined level, a person who is listening behind the audience can hear the singer's voice low, so this is a rear speaker installed behind the audience. The performance hall is designed so that the time is delayed and the sound is attenuated from the volume of the front speaker and output so that the sound from the rear speaker can be heard by the listener as if it were the same as the sound from the stage (front speaker). Etc. are designed.

  Here, as shown in FIG. 5 (a), a center speaker CE, left and right front speakers FL and FR, left and right rear speakers RL and RR, and a woofer WF are installed in the passenger compartment of the automobile, and the position of the symbol P is set. Consider the case where there is a listener in the (rear seat). Assume that a sound of level A shown in FIG. 5B is reproduced from the center speaker CE at time t0. The dotted line that attenuates with the passage of time from the position of the sound of level A is the attenuation characteristic indicating the above-mentioned law. Subsequently, it is assumed that the same sound of level B is reproduced from the right front speaker FR at time t1 slightly delayed from time t0. At this time, if the level B is smaller than the attenuation characteristic, the listener P does not hear the sound of the level B as if it was emitted from the right front speaker FR, but comes out of the center speaker CE where the sound of the level A is reproduced. Sounds as one sound.

However, it is assumed that the same level C sound is reproduced from the right rear speaker RR at time t2 when the time is further delayed. At this time, if the level C is larger than the attenuation characteristic, the listener P does not hear the sound of the level C as if it is emitted from the center speaker CE, but sounds like another sound emitted from the right rear speaker RR. End up.
Therefore, the delay characteristic of the delay circuit 22 and the attenuation characteristic of the amplifier 23 in each signal processing circuit 20 are based on this “first wavefront law”. As a result, in the vehicle interior acoustic system of the first embodiment, when a DVD recorded with a multi-channel source is reproduced from a plurality of speakers, a sound close to the original sound recorded on each channel of the DVD is heard by the listener. It becomes possible to reproduce at the position.

  FIG. 4 shows the configuration of a modified embodiment of the matrix delay addition processing circuit 6 of the first embodiment of FIG. The only difference between the modified embodiment shown in FIG. 4 and the first embodiment is that the equalizer 21 is removed from each signal processing circuit 20, and the method of adding the signal to each speaker to the signal to the other speaker is as follows. The same as in the first embodiment. Thus, if the equalizer 21 is removed from each signal processing circuit 20, the degree of freedom in acoustic correction is slightly reduced, but the amount of arithmetic processing is reduced, so that the circuit configuration can be reduced in size.

  FIG. 6 shows the configuration of the second embodiment of the matrix delay addition processing circuit 6 of FIG. In the first embodiment, the sound output from the center speaker CE and the sound output from the left and right front speakers FL and FR are adjusted and added to the sound output from the left and right rear speakers RL and RR. Sounds output from the left and right rear speakers RL and RR are adjusted and added to and output from the left and right front speakers FL and FR and the center speaker CE, respectively. On the other hand, in the second embodiment, the sound output from the center speaker CE and the sound output from the left and right front speakers FL, FR are adjusted and added to the sound output from the left and right rear speakers RL, RR. The point is the same as in the first embodiment, but the sound output from the left and right rear speakers RL and RR is adjusted and added only to the left and right front speakers FL and FR, but not to the center speaker CE. Is different from the first embodiment. This is because the left and right front speakers FL, FR and the center speaker CE are both forward when viewed from the rear side, so that the same effect can be obtained without adding the sounds of the left and right rear speakers RL, RR to the center speaker CE. It is because it is obtained.

  FIG. 7 shows the configuration of the third embodiment of the matrix delay addition processing circuit 6 of FIG. In the first and second embodiments, the signal to each speaker on the front side is added to the signal to each speaker on the rear side, or the signal to each speaker on the rear side is added to the signal to each front side speaker. When the signal delay circuit 20 is added to the signal, the signal delay circuit 20 is individually connected between the signal lines to the respective speakers. On the other hand, in the third embodiment, when the signal to each speaker on the front side is added to the signal to each speaker on the rear side, the signal to each speaker on the front side is added in advance, and the added signal Is applied to each speaker on the rear side via one signal processing circuit 20, and when the signal to each speaker on the rear side is added to the signal to each speaker on the front side, to each speaker on the rear side. Are different from each other in that the added signals are added to each speaker on the front side via one signal processing circuit 20.

  Therefore, in the third embodiment, as shown in FIG. 7, the signal SCE to the center speaker CE, the signal SFL to the left front speaker FL, and the signal SFR to the right front speaker FR are branched and gained respectively. The signal is input to the adder 32 through the adjuster 31. The adder 32 adds the signal SCE to the center speaker CE, the signal SFL to the left front speaker FL, and the signal SFR to the right front speaker FR to generate a composite signal MF, which is input to the signal processing circuit 20. .

  The signal processing circuit 20 has the same configuration as that of the first and second embodiments, and includes an equalizer 21, a delay circuit 22, and an amplifier 23. The composite signal MF input to the signal processing circuit 20 is delayed by the time dt by the delay circuit 22 after the frequency characteristic is adjusted by the equalizer 21 and branched after the gain is adjusted in the attenuation direction by the amplifier 23. It is added to the signal SRL to the left speaker RL and the signal SRR to the right rear speaker RR, respectively.

  Conversely, a signal SRL to the left rear speaker RL and a signal SRR to the right rear speaker RR are also branched and input to the adder 32 through the gain adjuster 31. The adder 32 adds the signal SRL to the left rear speaker RL and the signal SRR to the right rear speaker RR to generate a composite signal MR, which is input to the signal processing circuit 20. The synthesized signal MR input to the signal processing circuit 20 is delayed by the time dt by the delay circuit 22 after the frequency characteristic is adjusted by the equalizer 21 and branched after the gain is adjusted by the amplifier 23 in the attenuation direction. It is added to the signal SCE to the center speaker CE, the signal SRL to the left speaker RL, and the signal SRR to the right rear speaker RR, respectively.

  Also in the third embodiment, the delay time of the delay circuit 22 of the signal processing circuit 20 and the attenuation characteristic of the gain of the amplifier 23 are determined in accordance with the “first wavefront law” explained with reference to FIG. In the third embodiment, the amount of signal processing is reduced by ignoring a slight difference in delay time between each speaker on the front side and each speaker on the rear side. In a narrow cabin such as an automobile, a certain effect can be obtained even if a slight difference in delay time between each speaker on the front side and each speaker on the rear side is ignored.

  FIG. 8 shows a configuration of a modified embodiment of the matrix delay addition processing circuit 6 of the third embodiment of FIG. The modified embodiment shown in FIG. 7 is different from the third embodiment only in that the equalizer 21 is removed from each signal processing circuit 20, and a method for adding signals to each speaker to signals to other speakers is as follows. The same as in the third embodiment. Thus, if the equalizer 21 is removed from each signal processing circuit 20, the degree of freedom in acoustic correction is slightly reduced, but the amount of arithmetic processing is reduced, so that the circuit configuration can be reduced in size.

FIG. 9 shows the configuration of the fourth embodiment of the matrix delay addition processing circuit 6 of FIG. The fourth embodiment is different from the third embodiment only in how the output of the signal processing circuit 20 is added to the left and right front speakers FL and FR and the left and right rear speakers RL and RR.
In the third embodiment, the output of the signal processing circuit 20 is applied to the left and right front speakers FL, FR and the left and right rear speakers RL, RR with the same gain. On the other hand, in the fourth embodiment, a plurality of amplifiers 23 of each signal processing circuit 20 are provided independently according to the number of output destination lines. Therefore, if the gain of each amplifier 23 can be adjusted, the level of the reproduced sound from each speaker can be adjusted by adjusting the gain of each amplifier 23 according to the position of the listener sitting in the passenger compartment. Can be adjusted accordingly.

FIG. 10 shows the configuration of the fifth embodiment of the matrix delay addition processing circuit 6 of FIG. The fifth embodiment is different from the third embodiment only in that a plurality of signal processing circuits 20 are provided in accordance with the number of output destination lines.
In the third embodiment, the output of the signal processing circuit 20 is applied to the left and right front speakers FL, FR and the left and right rear speakers RL, RR with the same gain. On the other hand, in the fifth embodiment, a plurality of signal processing circuits 20 are provided independently according to the number of output destination lines. Accordingly, if the delay time of each delay circuit 22 of each signal processing circuit 20 and the gain of each amplifier 23 can be adjusted, the delay time of each delay circuit 22 and each amplifier according to the position of the listener sitting in the passenger compartment. By adjusting the gain of 23, the level of the reproduced sound from each speaker can be appropriately adjusted according to the position of the listener. In the fifth embodiment, only the delay time of the delay circuit 22 of the signal processing circuit 20 connected to the signal SCE to the center speaker CE of the delay circuit 22 is different from other delay times.

  FIG. 11 shows the relationship between the seat priority mode and the gain of each speaker in an application example to a three-row seat vehicle. In this embodiment, when seats are arranged in three rows in the vehicle interior of the automobile, in this embodiment, it is possible to switch which row of seats is given priority to the sound for the listener sitting on the seat. When giving priority to the seats in the first row, the sound pressure of the left and right rear speakers RL and RR is increased by switching the mode to the first row seat priority mode. At this time, the sound pressures of the left and right front speakers FL and FR and the center speaker CE are maintained at a medium level. Also, when giving priority to the second row seats, the mode is switched to the second row seat priority mode, so that the sound pressures of the left and right rear speakers RL and RR, the sound pressures of the left and right front speakers FL and FR, and The sound pressures of the center speakers CE are all kept at the same medium level. Furthermore, when giving priority to the seats in the third row, the sound pressure of the left and right rear speakers RL, RR becomes medium by switching the mode to the third row seat priority mode, and the left and right front speakers FL, FR and The sound pressure of the center speaker CE increases.

Thus, the sound processing apparatus according to the present invention can be effectively applied to a sound system in a vehicle interior of a three-row seat automobile.
In the above embodiments, the sound processing apparatus and sound processing method using a DVD player have been described, but the multi-channel playback apparatus is not particularly limited to a DVD player.

  In the embodiment described above, the acoustic processing device and the acoustic processing method in the vehicle interior have been described. However, the present invention is also applicable to the case where the acoustic signal reproduced by the multichannel reproduction device is reproduced in a normal room. It can be applied effectively.

It is a perspective view which shows the installation position of the several speaker of the motor vehicle provided with the sound processing apparatus which concerns on this invention. It is a block diagram explaining the structure of the sound processing apparatus which concerns on this invention. FIG. 3 is a block circuit diagram showing a configuration of a first example of a matrix delay addition processing circuit of FIG. 2; FIG. 5 is a block circuit diagram showing a configuration of a modification of the matrix delay addition processing circuit of the first exemplary embodiment of FIG. 3; (a) is explanatory drawing explaining the delay time in the circuit of FIG. 3, FIG. 4, (b) is a characteristic view explaining the delay time and gain control in the circuit of FIG. 3, FIG. FIG. 3 is a block circuit diagram showing a configuration of a second embodiment of the matrix delay addition processing circuit of FIG. 2; FIG. 6 is a block circuit diagram showing a configuration of a third embodiment of the matrix delay addition processing circuit of FIG. 2. FIG. 10 is a block circuit diagram showing a configuration of a modified example of the matrix delay addition processing circuit of the third example of FIG. 7; FIG. 9 is a block circuit diagram showing a configuration of a fourth example of the matrix delay addition processing circuit of FIG. 2; FIG. 10 is a block circuit diagram showing a configuration of a fifth embodiment of the matrix delay addition processing circuit of FIG. 2; It is a figure which shows the relationship between the seat priority mode and the gain of each speaker in the example applied to a 3 row seat vehicle.

Explanation of symbols

1 Multi-channel playback device (DVD player)
2 Amplifier unit 3 Receiver circuit 4 DSP
5 Decoder 6 Matrix Delay Addition Processing Circuit 7 Equalizer 10 Audio Unit 11-16 Amplifier 20 Signal Processing Circuit 21 Equalizer 22 Delay Circuit 23 Amplifier 31 Gain Controller 32 Adder CE Center Speaker FL Left Front Speaker FR Right Front Speaker RL Left Rear Speaker RR Right rear speaker WF Woofer

Claims (20)

Acoustic signal generating means for generating and outputting at least three acoustic signals from a reproduction signal from an acoustic source;
A branch stage for branching at least one of the acoustic signals from the acoustic signal generating means to extract a branched signal;
An addition stage for adding a branch signal from the branch stage to an acoustic signal other than the branch signal at the branch stage;
The branch signal is delayed based on the distance between the reproduction position of the acoustic signal from which the branch signal is extracted in the branch stage and the reproduction position of the acoustic signal to which the branch signal is added in the addition stage, and the branch signal And a processing stage for adjusting the level of the sound processing apparatus.   The sound processing apparatus according to claim 1, wherein the processing stage further corrects a frequency characteristic of the branch signal.   The at least three acoustic signals are a left front acoustic signal reproduced on the front left side, a right front acoustic signal reproduced on the front right side, and a rear acoustic signal reproduced on the rear side with respect to the listening position. The sound processing apparatus according to claim 1, wherein:   The at least three acoustic signals are, with respect to the listening position, a left front acoustic signal reproduced on the front left side, a right front acoustic signal reproduced on the front right side, a center acoustic signal reproduced on the front center, and The sound processing apparatus according to claim 1, wherein the sound processing apparatus is a rear sound signal reproduced rearward.   The sound processing apparatus according to claim 4, wherein a branch signal is generated from the center sound signal and added to the rear sound signal.   6. The sound processing device according to claim 3, wherein a branch signal is generated from the left front sound signal and the right front sound signal, and is added to the rear sound signal. .   The at least three acoustic signals are, for the listening position, a left front acoustic signal reproduced on the front left side, a right front acoustic signal reproduced on the front right side, and a left rear acoustic signal reproduced on the rear left side, The sound processing apparatus according to claim 1, wherein the sound processing apparatus is a right rear sound signal reproduced on the right rear side.   The at least three acoustic signals are, for the listening position, a left front acoustic signal reproduced on the front left side, a right front acoustic signal reproduced on the front right side, a center acoustic signal reproduced on the front center, and the rear The sound processing apparatus according to claim 1, wherein the sound processing apparatus is a left rear acoustic signal reproduced on the left side and a right rear acoustic signal reproduced on the rear right side.   9. The sound processing apparatus according to claim 8, wherein a branch signal is generated from the center sound signal and added to the left rear sound signal and the right rear sound signal.   A branch signal is generated from the left front acoustic signal and added to the left rear acoustic signal, and a branch signal is generated from the right front acoustic signal and added to the right rear acoustic signal. The sound processing apparatus according to any one of claims 6 to 9. Generating at least three acoustic signals from the reproduced signal from the acoustic source;
Branching at least one acoustic signal out of the acoustic signals to extract a branched signal;
Adding the branched signal to an acoustic signal other than the branched signal;
Based on the distance between the reproduction position of the acoustic signal from which the branch signal is extracted and the reproduction position of the acoustic signal to which the branch signal is added, the branch signal is delayed and the level of the branch signal is adjusted and processed. A sound processing method characterized by generating sound.   The acoustic processing method according to claim 11, further comprising correcting a frequency characteristic in generating the processed sound.   The at least three acoustic signals are a left front acoustic signal reproduced on the front left side, a right front acoustic signal reproduced on the front right side, and a rear acoustic signal reproduced on the rear side with respect to the listening position. The sound processing method according to claim 11 or 12, characterized in that:   The at least three acoustic signals are, with respect to the listening position, a left front acoustic signal reproduced on the front left side, a right front acoustic signal reproduced on the front right side, a center acoustic signal reproduced on the front center, and The acoustic processing method according to claim 11, wherein the acoustic processing method is a rear acoustic signal reproduced rearward.   The acoustic processing method according to claim 14, wherein a branch signal is generated from the center acoustic signal and added to the rear acoustic signal.   The acoustic processing method according to any one of claims 13 to 15, wherein a branch signal is generated from the left front acoustic signal and the right front acoustic signal, and is added to the rear acoustic signal.   The at least three acoustic signals are, for the listening position, a left front acoustic signal reproduced on the front left side, a right front acoustic signal reproduced on the front right side, and a left rear acoustic signal reproduced on the rear left side, The sound processing method according to claim 11, wherein the sound processing method is a right rear sound signal reproduced on the right rear side.   The at least three acoustic signals are, for the listening position, a left front acoustic signal reproduced on the front left side, a right front acoustic signal reproduced on the front right side, a center acoustic signal reproduced on the front center, and the rear The acoustic processing method according to claim 11 or 12, wherein the acoustic signal is a left rear acoustic signal reproduced on the left side and a right rear acoustic signal reproduced on the rear right side.   19. The acoustic processing method according to claim 18, wherein a branch signal is generated from the center acoustic signal and added to the left rear acoustic signal and the right rear acoustic signal.   A branch signal is generated from the left front acoustic signal and added to the left rear acoustic signal, and a branch signal is generated from the right front acoustic signal and added to the right rear acoustic signal. The sound processing method according to any one of claims 16 to 19.

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