JP6091247B2 - In-vehicle audio system and computer program - Google Patents

Description

  The present invention relates to an in-vehicle audio system mounted on an automobile, and a technique for outputting the sound of each sound source so that a user in each area of the vehicle can listen to sound of a sound source that is different for each area. It is about.

  In an in-vehicle audio system installed in an automobile, a technology for outputting the sound of each sound source so that a user in each area of the vehicle can listen to sound of a sound source different from area to area can be A speaker, a rear speaker, an FH speaker provided in the vicinity of the headrest of the front seat, and an RH speaker provided in the vicinity of the headrest of the rear seat. When outputting the sound of the sound source for the rear seat to the user in the rear seat, the front speaker and the FH speaker output the sound in which the high frequency and low frequency of the sound source for the front seat are attenuated, and the rear speaker and the RH. A technique for outputting a sound in which the high frequency and low frequency of a sound source for a rear seat is attenuated is known for a speaker (for example, Patent Document 1).

JP 2002-264732 A

  The front speaker and the FH speaker described above output sound in which the high frequency and low frequency of the sound source for the front seat are attenuated, and the high frequency and low frequency of the sound source for the rear seat are output to the rear speaker and the RH speaker. According to the technology for outputting sound with attenuated sound, only the sound with attenuated high and low frequencies of the sound source is output to the user at each seat, and the sound heard by the user is mainly in the middle frequency band. It becomes a low-quality voice having only. That is, according to this technology, for example, when the sound of the sound source is music, the music that the user listens to is inevitably poor including only mid-range sounds.

  In addition, the sound output from the rear speaker reaches the front seat and the sound output from the front speaker reaches the rear seat. In the mid-range where there is a great influence, it cannot be fully excluded that the sound of the sound source for the front seat and the sound of the sound source for the rear seat are mixed and heard by the user at each seat. The user may not be able to listen to the sound of the sound source for the seat satisfactorily.

  Therefore, the present invention provides an audio system mounted on a vehicle, wherein each user in each area in the vehicle can listen to the sound of a different sound source for each area with higher quality and better. It is an object to output the sound of

In order to achieve the above object, the present invention is arranged in an audio system mounted in an automobile at a position near a front seat, a front speaker arranged in the front of the vehicle compartment, a rear speaker arranged in the rear of the vehicle compartment. A front seat speaker, a rear seat speaker disposed in the vicinity of the rear seat, a front audio processing unit that adjusts a frequency characteristic of audio and outputs the same to the front speaker, and a frequency characteristic of audio that adjusts the rear A rear audio processing unit that outputs to the speaker, a front seat audio processing unit that adjusts the frequency characteristic of the audio and outputs it to the front seat speaker, and a rear seat audio that adjusts the frequency characteristic of the audio and outputs it to the rear seat speaker When a sound source for a front seat user and a sound source for a rear seat user are set as different sound sources for the front seat user and the front sound processing unit, The frequency characteristic is adjusted by a gain characteristic that attenuates a predetermined frequency band of the sound output from the sound source for the user, and the adjusted sound is output to the front speaker, and the front seat sound processing unit Adjusting the frequency characteristics by a gain characteristic that attenuates a frequency band other than the predetermined frequency band of the sound output from the sound source for the user at the front seat more than the predetermined frequency band; and The output to the front seat speaker is performed, and the rear sound processing unit adjusts the frequency characteristic by a gain characteristic that attenuates the predetermined frequency band of the sound output from the sound source for the user in the rear seat; The adjusted sound is output to the rear speaker, and the predetermined frequency band of the sound output from the sound source for the user in the rear seat is made to the rear seat sound processing unit. Voice and adjustment of the frequency characteristics by the gain characteristics to greatly attenuate than the outer frequency bands the predetermined frequency band, with causing the output to the rear seat speaker for audio after the adjustment, the predetermined frequency band The frequency band that constitutes the middle frequency band or a part of the frequency band.

Here, in such an in-vehicle audio system, the predetermined frequency band may be a band having 600 Hz as a center frequency on a logarithmic frequency axis. Alternatively, the predetermined frequency band may be a band between 120 Hz and 3 kHz.

  In the above-described in-vehicle audio system, the front seat speaker may be disposed in the vicinity of the front seat headrest, and the rear seat speaker is in the vicinity of the rear seat headrest. It may be arranged at a position. Alternatively, at least one front seat speaker may be disposed on each side of the front seat headrest, and at least one rear seat speaker is disposed on both sides of the rear seat headrest. It may be arranged.

  According to such an in-vehicle audio system, when different sound sources are set as the sound source for the front seat user and the sound source for the rear seat user, the sound of the sound source for the front seat user is predetermined from the front speaker. Outputs audio with the frequency band attenuated, and outputs audio from the front seat speaker with the frequency band other than the predetermined frequency band of the sound of the sound source for the user at the front seat attenuated more than the predetermined frequency band In addition, a sound obtained by attenuating a predetermined frequency band of the sound of the sound source for the rear seat user from the rear speaker is output, and the sound of the sound of the sound source for the user of the rear seat is output from the rear seat speaker other than the predetermined frequency band. Is output with the frequency band of which is attenuated to be larger than the predetermined frequency band.

  Here, the front seat speaker is a speaker dedicated to the user seated in the front seat, and is disposed in the vicinity of the front seat and therefore in the vicinity of the user seated in the front seat. The speaker for a seat is a speaker dedicated to the user seated in the rear seat, and the output volume is set to be relatively small because the seat speaker is disposed in the vicinity of the rear seat, that is, in the vicinity of the user seated in the rear seat. Therefore, by these settings, the sound output from the front seat speaker does not reach the rear seat user, and the sound output from the rear seat speaker does not reach the front seat user. In addition, the front seat speaker does not cause inconvenience even if it has a strong directivity in the front seat user direction, and the rear seat speaker does not have inconvenience even if it has a strong directivity in the rear seat user direction. Absent. By providing directivity in this way, the sound output from the front seat speaker does not reach the rear seat user, and the sound output from the rear seat speaker reaches the front seat user more effectively. Can not be.

  In addition, the predetermined frequency band can be set in the middle range of the voice, so that the front seat user can hear the voice heard by the front seat user from the front speaker. For the sound source of the sound source, the mid-frequency component of the sound of the sound source for the front seat user that is output from the front seat speaker, and the rear seat user who hears small because it is output from the far rear speaker It becomes the high and low frequency component of the sound of the sound source. Here, by adding the high and low frequency components of the sound of the sound source for the front seat user output from the front speaker and the mid frequency components of the sound of the sound source for the front seat user output from the front seat speaker, The user can hear the sound of the sound source for the front seat user who has the entire frequency band. Therefore, the front seat user can listen to the sound of the sound source for the front seat user with high quality. In addition, since the front seat user does not hear the sound of the sound source for the user in the rear seat in the middle region that has a great influence on the deterioration of the perceptual recognition, the sound source for the user in the front seat is not heard. You will be able to listen to audio well.

  Similarly, for the rear seat user, the sound heard by the rear seat user is output from the high and low frequency components of the sound of the sound source for the rear seat user output from the rear speaker and the rear seat speaker. It becomes a mid-range component of the sound of the sound source for the user at the rear seat and a high-low frequency component of the sound of the sound source for the user at the front seat that is heard small because it is output from a distant front speaker. Here, by adding the high and low frequency components of the sound of the sound source for the rear seat user output from the rear speaker and the mid range component of the sound of the sound source for the rear seat user output from the rear seat speaker, The user can hear the sound of the rear source having the entire frequency band. Therefore, the rear seat user can listen to the sound of the sound source for the rear seat user with high quality. In addition, since the rear seat user does not hear the sound of the sound source for the front seat user in the middle region, which has a large influence on the deterioration of the perceptual recognition, the sound source for the rear seat user is not heard. You will be able to listen to audio well.

  In the above-described in-vehicle audio system, when a common sound source is set for the front seat user and the rear seat user in the control unit, the front sound processing unit receives the common sound source from the common sound source. Adjustment of frequency characteristics by a predetermined gain characteristic prepared for a case where a common sound source is set for the front seat user and the rear seat user of the output sound, and the sound after the adjustment The output to the front speaker is performed, the output of the audio to the front seat speaker of the front seat audio processing unit is suppressed, and the predetermined output of the audio output from the common sound source to the rear audio processing unit The frequency characteristic is adjusted by the gain characteristic and the adjusted sound is output to the rear speaker, and the output of the sound to the rear seat speaker of the rear seat sound processing unit is suppressed. May be.

  In addition, when the above-mentioned in-vehicle audio system is provided with a subwoofer speaker, and the sound source for the front seat user and the sound source for the rear seat user are set differently in the control unit, the sound of the subwoofer speaker is set. The output is suppressed, and when a common sound source is set for the front seat user and the rear seat user, the sound output from the common sound source is output from the subwoofer speaker. Also good.

  As described above, according to the present invention, in an in-vehicle audio system mounted on a vehicle, each user in each area in the vehicle can listen to the sound of a sound source that is different for each area with higher quality and better. As described above, the sound of each sound source can be output.

It is a block diagram which shows the structure of the audio system which concerns on embodiment of this invention. It is a figure which shows arrangement | positioning of the audio system which concerns on embodiment of this invention. It is a figure which shows the audio output setting table which concerns on embodiment of this invention. It is a figure which shows the gain characteristic of the mid range attenuation pattern which concerns on embodiment of this invention, and a high-low range attenuation pattern. It is a flowchart which shows the audio output setting control process which concerns on embodiment of this invention.

Hereinafter, embodiments of the present invention will be described.
FIG. 1 shows a configuration of an AV (audio / visual) system according to the present embodiment.
Here, the AV system according to the present embodiment is an AV system mounted on an automobile,
As shown in the figure, a plurality of video source devices 1 that output video such as a TV receiver and a video disc player, a plurality of audio source devices 2 that output audio such as a radio receiver and an audio disc player, an input device 3, and a control Unit 4, front display 5, rear display 6, front speaker set 7, rear speaker set 8, front seat shoulder speaker set 9 provided for each front seat (driver seat and front passenger seat), and rear seats A rear seat speaker set 10 and a subwoofer speaker 11 are provided for each.

Here, each of the front speaker set 7, the rear speaker set 8, the front seat shoulder speaker set 9, and the rear seat shoulder speaker set 10 includes a pair of a speaker for the R (right) channel and a speaker for the L (left) channel. Consists of speakers.
Here, as shown in FIGS. 2a and 2b, the control unit 4, the video source device 1 and the audio source device 2 are installed in the dashboard of the automobile, and the front display 5 is displayed on the dashboard to the front seat user. It is arranged to be exposed. The rear display 6 is installed on the ceiling between the front seat and the rear seat with the display surface facing the rear seat user. The input device 3 is, for example, a touch panel or a remote controller that is arranged on the display surface of the front display 5.

  The R channel speaker 71 of the front speaker set 7 is disposed on the front right door, and the L channel speaker 72 of the front speaker set 7 is disposed on the front left door. Further, the R channel speaker 81 of the rear speaker set 8 is arranged at a position slightly behind the rear right door in the vehicle, and the L channel speaker 82 of the rear speaker set is slightly behind the rear left door in the vehicle. Placed in position. Moreover, the subwoofer speaker 11 is arrange | positioned in the rear luggage compartment.

  The front seat shoulder speaker set 9 is provided corresponding to each seat of the front seat, and as shown in FIG. 2c, the R channel speaker 91 of the front seat shoulder speaker set 9 is located on the right side of the headrest of the corresponding seat. The left channel speaker 92 of the front seat shoulder speaker set 9 is disposed facing the left front side of the headrest.

  The rear-seat shoulder speaker set 10 is provided corresponding to each seat in the rear seat. Like the front-seat shoulder speaker set 9, the R-channel speaker 101 of the rear-seat shoulder speaker set 10 is a headrest of the corresponding seat. The L channel speaker 102 of the rear seat shoulder speaker set 10 is disposed facing the right front side toward the left side of the headrest.

  Returning to FIG. 1, the control unit 4 includes two video decoders 401 for decoding video data and audio data from encoded video data input from the video source device 1, and encoded audio data input from the bi-audio source device. From the front video processing unit 410 and the video decoder 401 that perform adjustment processing on the video represented by the video data input from the two audio decoders 402, the control unit 403, and the video decoder 401 and outputs them to the front display 5. Corresponding to the rear video processing unit 411 that adjusts the video represented by the input video data and outputs it to the rear display 6, the front audio processing unit 412 provided corresponding to the front speaker set 7, and the rear speaker set 8. Rear audio processing unit 13. A front seat shoulder sound processing unit 414 provided corresponding to the front seat shoulder speaker set 9, a rear seat shoulder sound processing unit 415 provided corresponding to the rear seat shoulder speaker set 10, and a subwoofer sound processing unit 416. I have.

  The front audio processing unit 412 includes two sets of an equalizer (EQ) 421, a DA converter (DAC) 422, and an amplifier 423 for the R channel and the L channel. The set for the R channel of the front audio processing unit 412 is an equalizer 421, and the frequency characteristic of the R channel audio data output from the video decoder 401 or the audio decoder 402 to the front audio processing unit 412 is transmitted from the control unit 403. The analog sound signal is converted by the DA converter 422 after being changed with the specified gain characteristic, and the converted analog sound signal is amplified by the amplifier 423 at the amplification factor specified by the control unit 403 and used for the front speaker R channel. Is output to the speaker 71. The set for the L channel of the front audio processing unit 412 is an equalizer 421, and the frequency characteristic of the L channel audio data output from the video decoder 401 or the audio decoder 402 to the front audio processing unit 412 is transmitted from the control unit 403. After changing with the specified gain characteristics, the DA converter 422 converts the analog audio signal to an analog audio signal, and the amplifier 423 amplifies the converted analog audio signal with the amplification factor specified by the control unit 403, for the front speaker L channel. Is output to the speaker 72.

  Next, as with the front audio processing unit 412, the rear audio processing unit 413, the front seat shoulder audio processing unit 414, and the rear seat shoulder audio processing unit 415 also include a set of an equalizer 421, a DA converter (EQ) 422, and an amplifier 423. Two sets are provided for the R channel and the L channel. Then, the rear audio processing unit 413, the front seat shoulder audio processing unit 414, and the rear seat shoulder audio processing unit 415 are respectively frequency characteristics of R / L channel audio data output from the video decoder 401 or the audio decoder 402 to itself. Is changed with the gain characteristic designated by the control unit 403 and converted to an analog audio signal, and the converted analog audio signal is amplified with the amplification factor designated by the control unit 403, and the R / L of the corresponding speaker set is amplified. Output to the channel speaker.

  However, since the front seat shoulder speaker set 9 and the rear seat shoulder speaker set 10 are arranged near the user's ear, the volume of sound output from the front seat shoulder speaker set 9 and the rear seat shoulder speaker set 10 is large. The size needs to be smaller than the volume of sound output from the front speaker set 7 and the rear speaker set 8. Therefore, for example, the control unit 403 determines the amplification factors of the amplifiers 423 of the front seat shoulder audio processing unit 414 and the rear seat shoulder audio processing unit 415 as audio output from the front seat shoulder speaker set 9 and the rear seat shoulder speaker set 10. Is set to be smaller at a constant ratio than the volume of sound output from the front speaker set 7 and the rear speaker set 8.

The subwoofer audio processing unit 416 includes a DA converter and an amplifier 422, amplifies the audio represented by the audio data output from the audio decoder 402 with the amplification factor specified by the control unit 403, and outputs the amplified audio to the subwoofer speaker 11. To do. Note that the audio band output from the subwoofer speaker 11 is only low.
However, the control unit 4 described above may be configured using a computer having a general configuration including a microprocessor, a memory, and other peripheral devices in terms of hardware. In this case, the video decoder 401 Alternatively, the audio decoder 402, the control unit 403, and the equalizer 421 of each audio processing unit may be realized by a microprocessor executing a program prepared in advance.

Now, in such a configuration, the audio system has a 1-zone mode and a 2-zone mode as operation modes.
Then, the control unit 403 performs processing for switching the operation mode between the 1-zone mode and the 2-zone mode in accordance with the user operation received by the input device 3.
In addition, the control unit 403 performs processing for switching a source device (video source device 1 or audio source device 2) to be set as a source in accordance with a user operation received by the input device 3. Here, when the 1-zone mode is set as the operation mode, only the common source can be set as the source, and the control unit 403 can determine the user operation received by the input device 3 according to the user operation. Any video source device 1 or audio source device 2 is set as a common source. In addition, when the two-zone mode is set as the operation mode, the front source and the rear source can be set as the source, and the control unit 403 can perform the user operation received by the input device 3. Accordingly, any one of the video source device 1 or the audio source device 2 is set as the front source, and any one of the video source device 1 or the audio source device 2 is set according to the user operation received by the input device 3. Set as rear source. However, setting the same device (video source device 1 or audio source device 2) as the front source and the rear source is prohibited.

Hereinafter, an audio output setting control operation performed by the control unit 403 in accordance with such an operation mode and source setting will be described.
First, the audio output setting table set in the control unit 403 in advance for controlling the audio output setting will be described.
FIG. 3 shows the contents of the audio output setting table.
As shown in the figure, in the audio output setting table, the presence / absence of output of each audio processing unit, the source, and the setting of the equalizer 421 are registered for each of the 1 zone mode and the 2 zone mode. Here, the presence / absence of output indicates the setting of whether or not to output sound from the sound processing unit, and the source is the audio data input to the sound processing unit, that is, the speaker / speaker set corresponding to the sound processing unit. The setting of the source of the sound to be output is represented, and the equalizer setting represents the setting of the gain characteristic of the equalizer 421 of the sound processing unit.

  That is, as shown in the figure, in the audio output setting table, in the 1-zone mode, audio output of audio data using a common source as a sound source from the front audio processing unit 412, the rear audio processing unit 413, and the subwoofer audio processing unit 416 is performed. It is registered that no audio output is performed from the front seat shoulder audio processing unit 414 and the rear seat shoulder audio processing unit 415.

  In the audio output setting table, it is registered that the gain characteristics of the equalizers 421 of the front audio processing unit 412 and the rear audio processing unit 413 are set to standard gain characteristics in the 1-zone mode. Here, the standard gain characteristic is a gain characteristic in which the gain is uniform (flat) over the entire frequency band, or a gain characteristic separately set for the one-zone mode by the user.

  In the audio output setting table, in the two-zone mode, the front audio processing unit 412 and the front seat shoulder audio processing unit 414 output audio data using the front source as a sound source, and the rear audio processing unit 413. It is registered that the rear seat shoulder audio processing unit 415 outputs audio data of audio data using the rear source as a sound source, and the subwoofer audio processing unit 416 does not output audio.

  Further, in the audio output setting table, in the two-zone mode, the gain characteristics of the equalizer 421 of the front audio processing unit 412 and the rear audio processing unit 413 are set to the gain characteristics of the mid-range attenuation pattern, and the front seat shoulder audio processing is performed. It is registered that the gain characteristics of the equalizer 421 of the section 414 and the rear seat shoulder sound processing section 415 are set to the gain characteristics of the high / low range attenuation pattern.

Here, the gain characteristic of the mid-range attenuation pattern is a gain characteristic that attenuates the mid-range frequency band. For example, as shown by 301 in FIG. 4a, the center frequency on the logarithmic frequency axis is set to 600 Hz and 120 Hz− This is a gain characteristic that attenuates the mid frequency band of 3 kHz. Further, the gain characteristic of the high and low band attenuation pattern is a gain characteristic that attenuates the frequency band of the high and low band other than the middle band. For example, as shown by 302 in FIG. Gain characteristics that attenuate the band. That is, for the gain characteristic 301 of the mid-range attenuation pattern that attenuates the mid-frequency band of 120 Hz-3 kHz, the gain characteristics of the high-low-frequency attenuation pattern are high and low other than the mid-frequency band of 120 Hz-3 kHz. A gain characteristic that attenuates the middle frequency band is used.

More specifically, the gain characteristic of the high / low range attenuation pattern may be experimentally determined and set in advance as follows.
That is, for example, the music for test is output from only the front speaker set 7 with the gain characteristic of the equalizer 421 of the front audio processing unit 412 as a flat gain characteristic, and the sound at the position where the ear of the user sitting in the front seat is placed The frequency spectrum of the pressure is measured and used as a reference frequency spectrum (eg, 310 in FIG. 4b).

  Then, the gain characteristic of the front seat shoulder sound processing unit 414 is changed while outputting test music from the front speaker set 7 using the gain characteristic of the equalizer 421 of the front sound processing unit 412 as the gain characteristic of the mid-range attenuation pattern. However, the music for test is also output from the front seat shoulder speaker set 9, and the frequency spectrum of the sound pressure (for example, 311 in FIG. 4b) at the position where the ear of the user sitting in the front seat is arranged is the reference frequency spectrum. Is set as the gain characteristic of the high-low range attenuation pattern used for the equalizer 421 of the front seat shoulder sound processing unit 414.

  Similarly, the gain characteristic of the equalizer 421 of the rear audio processing unit 413 is set to a flat gain characteristic so that test music is output from only the eight rear speaker sets, and the user's ear sitting in the back seat is placed at the position. The frequency spectrum of sound pressure is measured and used as a reference frequency spectrum.

  Then, using the gain characteristic of the equalizer 421 of the rear audio processing unit 413 as the gain characteristic of the mid-range attenuation pattern, while changing the gain characteristic of the rear seat shoulder audio processing unit 415 while outputting test music from the rear speaker set 8. On the other hand, the test seat music is also output from the rear seat shoulder speaker set 10, and the rear seat shoulder when the frequency spectrum of the sound pressure at the position where the user's ear sitting in the rear seat is closest to the reference frequency spectrum is used. The gain characteristic of the sound processing unit 415 is set as the gain characteristic of the high / low range attenuation pattern used for the equalizer 421 of the rear seat shoulder sound processing unit 415.

The audio output setting control process performed by the control unit 403 will be described below using such an audio output setting table.
FIG. 5 shows the procedure of the audio output setting control process.
As shown in the figure, in this process, occurrence of a change in either the operation mode or the source setting is monitored (step 502), and if a change occurs, a decoder is assigned to each source (step 502).
That is, in step 504, if the operation mode is the one-zone mode and the common source is the video source device 1, one video decoder 401 is assigned to the common source, and the video output from the common source to the assigned video decoder 401 is output. If video data and audio data are decoded from data and the operation mode is the one-zone mode and the common source is the audio source device 2, one audio decoder 402 is assigned to the common source, and the common source is assigned to the assigned audio decoder 402. The audio data is decoded from the encoded audio data output from.

  In step 504, if the operation mode is the two-zone mode and the front source is the video source device 1, one video decoder 401 is assigned to the front source, and the video output from the front source to the assigned video decoder 401 is displayed. If video data and audio data are decoded from data, the operation mode is the two-zone mode, and the front source is the audio source device 2, one audio decoder 402 is assigned to the front source, and the assigned audio decoder 402 is set to the front source. The audio data is decoded from the encoded audio data output from.

  In step 504, if the operation mode is the two-zone mode and the rear source is the video source device 1, one video decoder 401 not assigned to the front source is assigned to the rear source, and the assigned video decoder 401 is output from the rear source. If the video data and audio data are decoded from the video data, the operation mode is the two-zone mode, and the rear source is the audio source device 2, one audio decoder 402 not assigned to the front source is assigned to the rear source and assigned. The audio decoder 402 decodes the audio data from the encoded audio data output from the rear source.

Next, input to each video processing unit and each audio processing unit is set according to the operation mode, source setting, and audio output setting table (step 506).
That is, in step 506, when the operation mode is the one-zone mode and the common source is the video source device 1, the front video processing unit 410 and the rear video of the video data decoded by the video decoder 401 assigned to the common source. Controls start of output to the processing unit 411 and control of start of output of audio data decoded by the video decoder 401 assigned to the common source to the front audio processing unit 412, the rear audio processing unit 413, and the subwoofer audio processing unit 416. . When the operation mode is the one-zone mode and the common source is the audio source device 2, the audio data front audio processing unit 412, rear audio processing unit 413, audio data decoded by the audio decoder 402 assigned to the common source, Controls the start of output to the subwoofer audio processing unit 416.

  In step 506, when the operation mode is the two-zone mode and the front source is the video source device 1, the video data decoded by the video decoder 401 assigned to the front source is output to the front video processing unit 410. While controlling the start, it controls the start of output of the audio data decoded by the video decoder 401 assigned to the front source to the front audio processing unit 412 and the front seat shoulder audio processing unit 414. When the operation mode is the two-zone mode and the front source is the audio source device 2, the front audio processing unit 412 of the audio data decoded by the audio decoder 402 assigned to the front source, the front seat shoulder audio processing unit The start of output to 414 is controlled.

  In step 506, when the operation mode is the two-zone mode and the rear source is the video source device 1, output of the video data decoded by the video decoder 401 assigned to the rear source to the rear video processing unit 411 is started. At the same time, it controls the start of output of audio data decoded by the video decoder 401 assigned to the rear source to the rear audio processing unit 413 and the rear seat shoulder audio processing unit 415. When the operation mode is the two-zone mode and the rear source is the audio source device 2, the audio data decoded by the audio decoder 402 assigned to the rear source is decoded to the rear audio processing unit 413 and the rear seat shoulder audio processing unit 415. Controls the start of output.

Next, according to the operation mode and the audio output setting table, the output presence / absence of each audio processing unit and the gain characteristics of the equalizer 421 are set (step 508), and the processing returns to step 502.
That is, in step 508, if the operation mode is the one-zone mode, no output is set in the front seat shoulder audio processing unit 414 and the rear seat shoulder audio processing unit 415, and output is set in other audio processing units. The standard gain characteristic is set as the gain characteristic of the equalizer 421 of the front audio processing unit 412 and the rear audio processing unit 413. Here, the voice processing unit set to “no output” suppresses the voice output, and the voice processing unit set to “output enabled” does not suppress the voice output. Note that the suppression of the audio output can be realized, for example, by using the output of the amplifier 423.

  In step 508, if the operation mode is the two-zone mode, the subwoofer audio processing unit 416 is set to output no, the other audio processing units are set to output, and the front audio processing unit 412 and the rear audio processing are set. The gain characteristic of the mid-range attenuation pattern is set as the gain characteristic of the equalizer 421 of the unit 413, and the gain characteristic of the high-low range attenuation pattern is set as the gain characteristic of the front seat shoulder sound processing unit 414 and the rear seat shoulder sound processing unit 415. .

The audio output setting control process performed by the control unit 403 has been described above.
According to the audio output setting control process as described above, when the one-zone mode is set as the operation mode, the video source device 1 or the audio source set as the common source from the front speaker set 7 and the rear speaker set 8 is set. Sound using the device 2 as a sound source is output after the frequency characteristics are adjusted with standard gain characteristics, and a low frequency component of sound using the common source as a sound source is output from the subwoofer speaker 11. At this time, no sound is output from the front seat shoulder speaker set 9 and the rear seat shoulder speaker set 11.

  On the other hand, when the two-zone mode is set as the operation mode, the sound from the video source device 1 or the audio source device 2 set as the front source from the front speaker set 7 and the front seat shoulder speaker set 9 is generated. The rear speaker set 8 and the rear-seat shoulder speaker set 10 output sound that uses the video source device 1 or the audio source device 2 set as the rear source as a sound source. At this time, no sound is output from the subwoofer speaker 11.

  In addition, when the two-zone mode is set as described above, the sound output using the front source as a sound source is a high-low frequency component output from the front speaker set 7 and a medium output from the front seat shoulder speaker set 9. It becomes a band component. Further, when the 2-zone mode is set, the sound output using the rear source as a sound source is a high-low frequency component output from the rear speaker set 8 and a mid-frequency component output from the rear seat shoulder speaker set 10. .

The front seat shoulder speaker set 9 is a speaker dedicated to the user seated in the front seat, and is set near the ear of the user seated in the front seat, so that the output volume is set to be relatively small. The rear-seat shoulder speaker set 10 is a speaker dedicated to the user seated in the rear seat, and is arranged near the ear of the user seated in the rear seat, so that the output volume is set to be relatively small. For this reason, the sound output from the front seat shoulder speaker set 9 hardly reaches the rear seat user, and the sound output from the rear seat shoulder speaker set 10 hardly reaches the front seat user. Further, there is no inconvenience even if the front seat shoulder speaker set 9 is given strong directivity in the front seat user direction, and the rear seat shoulder speaker set 10 is given strong directivity in the rear seat user direction. There is no inconvenience. And by giving directionality in this way, the sound outputted from the front seat shoulder speaker set 9 does not reach the user in the rear seat more effectively, and the voice outputted from the rear seat shoulder speaker set 10 becomes more effective. It can be prevented from reaching the front seat user.
Therefore, the front seat user hardly hears the mid-range component of the rear source sound output from the rear seat shoulder speaker set 10, and the sound audible to the front seat user is output from the front speaker set 7. High- and low-frequency components of the front source sound, mid-range components of the front source sound output from the front seat shoulder speaker set 9, and high and low of the rear source sound that can be heard small because it is output from the far rear speaker set 8 It becomes a band component. Here, by adding the high and low frequency components of the sound of the front source output from the front speaker set 7 and the mid-frequency component of the sound of the front source output from the front seat shoulder speaker set 9, the front seat user is all You can hear the sound from the front source with the same frequency band. Therefore, the front seat user can listen to the sound of the front source with high quality. In addition, the user at the front seat can hear the sound of the front source satisfactorily because the user cannot hear the sound of the rear source in the middle region that has a great influence on the deterioration of the perceptual recognition. .

  Similarly, the rear seat user hardly hears the mid-frequency component of the front source sound output from the front seat shoulder speaker set 9, and the sound audible to the rear seat user is output from the rear speaker set 8. High and low frequency components of the rear source audio, mid range components of the rear source audio output from the rear seat shoulder speaker set 10, and high and low frequency components of the front source audio that are heard small because they are output from the distant front speaker set 7 It becomes. Here, the addition of the high and low frequency components of the rear source audio output from the rear speaker set 8 and the mid frequency components of the rear source audio output from the rear seat shoulder speaker set 10 allows the rear seat user to receive the entire frequency band. You will hear the sound of the rear source with Therefore, the rear seat user can listen to the sound of the rear source with high quality. In addition, the rear seat user can hear the rear source sound well in the middle range, which has a great influence on the deterioration of the perceptual recognition quality, so that the rear source sound can be heard satisfactorily. .

Incidentally, when the two-zone mode is set, the center sound high and low frequency component output from the front speakers and the rear speakers, the 600 Hz of the sound source of sound using the gain characteristic of the middle band attenuation pattern 120 The sound with attenuated frequency components in the Hz-3kHz range is the most meaningful audio component for listeners, such as music vocals and melody parts of musical instruments, in this frequency band. This is because if the sound of the different sound sources in this frequency band is mixed, the sound quality of each sound source is greatly deteriorated. In other words, by excluding audio components in the 120 Hz to 3 kHz frequency band centered at 600 Hz from the audio of the high and low frequency components output from the front speaker and the rear speaker, the main meaning of listening or listening For the frequency band that is the target of the sound, the sound that the user can hear is mixed with the sound of different sound sources, and the sound that the user can hear for the frequency band from the sound source that the user is listening to. Can only be voice.

However, the center frequency (on the logarithmic frequency axis) of such mid-range attenuation pattern need not be strictly 600 Hz.
The embodiment of the present invention has been described above.
In the above embodiment, a speaker set arranged at an arbitrary position near the front seat is used instead of the front seat shoulder speaker set 9, or an arbitrary position near the rear seat is used instead of the rear seat shoulder speaker set 10. A speaker set may be used.

  DESCRIPTION OF SYMBOLS 1 ... Video source device, 2 ... Audio source device, 3 ... Input device, 4 ... Control unit, 5 ... Front display, 6 ... Rear display, 7 ... Front speaker set, 8 ... Rear speaker set, 9 ... Front seat shoulder speaker Set: 10 ... Rear-seat shoulder speaker set, 11 ... Subwoofer speaker, 401 ... Video decoder, 402 ... Audio decoder, 403 ... Control unit, 410 ... Front video processing unit, 411 ... Rear video processing unit, 412 ... Front audio processing unit 413: Rear audio processing unit, 414 ... Front seat shoulder audio processing unit, 415 ... Rear seat shoulder audio processing unit, 416 ... Subwoofer audio processing unit, 421 ... Equalizer, 422 ... DA converter, 423 ... Amplifier.

Claims (11)

An audio system mounted on a car,
A front speaker arranged in front of the passenger compartment;
A rear speaker arranged at the rear of the passenger compartment;
A front seat speaker arranged near the front seat;
A rear seat speaker arranged near the rear seat;
A front sound processing unit that adjusts the frequency characteristics of the sound and outputs the sound to the front speaker;
A rear audio processing unit that adjusts the frequency characteristics of the audio and outputs to the rear speaker;
A front seat sound processing unit that adjusts the frequency characteristics of the sound and outputs the sound to the front seat speaker;
A rear-seat audio processing unit that adjusts the frequency characteristics of the audio and outputs to the rear-seat speaker;
A control unit,
When different sound sources are set as the sound source for the user at the front seat and the sound source for the user at the back seat,
The front audio processing unit adjusts the frequency characteristic by a gain characteristic that attenuates a predetermined frequency band of the sound output from the sound source for the front seat user, and outputs the adjusted sound to the front speaker. Let
Adjustment of frequency characteristics by a gain characteristic that causes the front seat audio processing unit to attenuate a frequency band other than the predetermined frequency band of the sound output from the sound source for the front seat user more than the predetermined frequency band; And outputting the adjusted sound to the front seat speaker,
Adjustment of frequency characteristics by gain characteristics for attenuating the predetermined frequency band of sound output from the sound source for the rear seat user to the rear sound processing unit, and output of the adjusted sound to the rear speaker Let
Adjusting the frequency characteristic by a gain characteristic that attenuates a frequency band other than the predetermined frequency band of the audio output from the sound source for the user in the rear seat to the rear seat audio processing unit to be larger than the predetermined frequency band; And outputting the adjusted audio to the rear seat speaker , and
The in-vehicle audio system, wherein the predetermined frequency band is a frequency band constituting a mid range of voice or a part of the frequency band . The in-vehicle audio system according to claim 1,
The in-vehicle audio system, wherein the predetermined frequency band is a band having 600 Hz as a center frequency on a logarithmic frequency axis. The in-vehicle audio system according to claim 1,
The in-vehicle audio system, wherein the predetermined frequency band is a band between 120 Hz and 3 kHz. The in-vehicle audio system according to claim 1, 2, or 3,
The front seat speaker is disposed at a position near the headrest of the front seat,
The in-vehicle audio system, wherein the rear seat speaker is disposed at a position near the headrest of the rear seat. The in-vehicle audio system according to claim 1, 2 or 3,
The front seat speaker is disposed at least one on each side of the front seat headrest,
The in-vehicle audio system according to claim 1, wherein at least one rear seat speaker is disposed on each side of the headrest of the rear seat. The in-vehicle audio system according to claim 1, 2, 3, 4 or 5,
When a common sound source is set for the front seat user and the rear seat user,
Frequency according to a predetermined gain characteristic prepared for a case where a common sound source is set for the front seat user and the rear seat user of the sound output from the common sound source in the front sound processing unit The adjustment of the characteristics and the output of the adjusted sound to the front speaker are performed,
Suppressing the output of audio to the front seat speaker of the front seat audio processing unit,
Causing the rear audio processing unit to adjust the frequency characteristics of the audio output from the common sound source according to the predetermined gain characteristics and to output the adjusted audio to the rear speaker;
An in-vehicle audio system, wherein output of audio to the rear seat speaker of the rear seat audio processing unit is suppressed. The in-vehicle audio system according to claim 6,
It has a subwoofer speaker
The controller is
When different sound sources are set as the sound source for the front seat user and the sound source for the rear seat user, the sound output of the subwoofer speaker is suppressed,
An in-vehicle audio system that outputs sound output from the common sound source from the subwoofer speaker when a common sound source is set for a front seat user and a rear seat user. Front speaker disposed in front of the passenger compartment, rear speaker disposed in the rear of the passenger compartment, speaker for front seats disposed in the vicinity of the front seat, and speaker for rear seats disposed in the vicinity of the rear seat A computer program that is read and executed by a computer installed in a car equipped with
The computer,
A front sound processing unit that adjusts the frequency characteristics of the sound and outputs the sound to the front speaker;
A rear audio processing unit that adjusts the frequency characteristics of the audio and outputs to the rear speaker;
A front seat sound processing unit that adjusts the frequency characteristics of the sound and outputs the sound to the front seat speaker;
A rear-seat audio processing unit that adjusts the frequency characteristics of the audio and outputs to the rear-seat speaker;
A rear seat frequency characteristic adjustment unit for adjusting the frequency characteristic;
Function as a controller,
When different sound sources are set as the sound source for the user at the front seat and the sound source for the user at the back seat,
The front audio processing unit adjusts the frequency characteristic by a gain characteristic that attenuates a predetermined frequency band of the sound output from the sound source for the front seat user, and outputs the adjusted sound to the front speaker. Let
Adjustment of frequency characteristics by a gain characteristic that causes the front seat audio processing unit to attenuate a frequency band other than the predetermined frequency band of the sound output from the sound source for the front seat user more than the predetermined frequency band; And outputting the adjusted sound to the front seat speaker,
Adjustment of frequency characteristics by gain characteristics for attenuating the predetermined frequency band of sound output from the sound source for the rear seat user to the rear sound processing unit, and output of the adjusted sound to the rear speaker Let
Adjusting the frequency characteristic by a gain characteristic that attenuates a frequency band other than the predetermined frequency band of the audio output from the sound source for the user in the rear seat to the rear seat audio processing unit to be larger than the predetermined frequency band; And outputting the adjusted audio to the rear seat speaker, and
The computer program according to claim 1, wherein the predetermined frequency band is a frequency band constituting a mid range of the voice or a part of the frequency band. An in-vehicle computer program according to claim 8,
The computer program according to claim 1, wherein the predetermined frequency band is a band having 600 Hz as a center frequency on a logarithmic frequency axis. A computer program according to claim 8,
The computer program according to claim 1, wherein the predetermined frequency band is a band between 120 Hz and 3 kHz. A computer program according to claim 8, 9 or 10,
When a common sound source is set for the front seat user and the rear seat user,
Frequency according to a predetermined gain characteristic prepared for a case where a common sound source is set for the front seat user and the rear seat user of the sound output from the common sound source in the front sound processing unit The adjustment of the characteristics and the output of the adjusted sound to the front speaker are performed,
Suppressing the output of audio to the front seat speaker of the front seat audio processing unit,
Causing the rear audio processing unit to adjust the frequency characteristics of the audio output from the common sound source according to the predetermined gain characteristics and to output the adjusted audio to the rear speaker;
A computer program for suppressing output of audio to the rear seat speaker of the rear seat audio processing unit.