JP7236932B2 - In-vehicle amplifier device - Google Patents

Description

The present invention relates to an in-vehicle amplifier device.

An in-vehicle sound system is generally equipped with four speakers: a right front speaker and a right rear speaker for outputting the right side signal of the stereo signal, and a left front speaker and a left rear speaker for outputting the left side signal of the stereo signal. target. Further, in order to output sound from each of the four speakers, the vehicle-mounted sound system generally includes an in-vehicle amplifier device having four amplifiers as amplifiers corresponding to the four speakers, respectively. is. In the conventional vehicle-mounted sound system, the vehicle-mounted amplifier device adjusts the amplification value or delay amount of each of the four amplifiers of the vehicle-mounted amplifier device, so that the sound output from each of the four speakers is is adjusted so that sound image localization in the driver's seat is good.

In addition to the four speakers described above, a center speaker is arranged between the right front speaker and the left front speaker, and the right signal is connected to the right front speaker, the left signal is connected to the left front speaker, and the center speaker By connecting a monaural signal that is the addition signal of the right signal and the left signal to the rear right speaker and a monaural signal that is the difference signal of the left signal to the rear right speaker and the rear left speaker, four speakers are connected. There is an in-vehicle sound system that uses amplifiers to output sounds from five speakers (Patent Document 1).

Japanese Patent Laid-Open No. 03-071798

When the right signal is output from the right rear speaker and the left signal is output from the left rear speaker, the sound image localization in the rear seat is dominated by the sound output from the right rear speaker or the left rear speaker near the rear seat. As a result, the bass range is small and the midrange and treble ranges are large. Therefore, in this case, there is a problem that sound image localization in the rear seats is not good.

SUMMARY OF THE INVENTION It is an object of the present invention to solve the above-described problems, and to provide an on-vehicle amplifier device capable of improving sound image localization for all seats in a vehicle.

A vehicle-mounted amplifier device according to the present invention includes a first amplifier that amplifies a right side signal of a stereo signal and outputs the amplified right side signal as a right side output signal to a right front speaker mounted on a vehicle 1; A second amplifier that amplifies the left signal, outputs the amplified left signal as a left output signal to the front left speaker mounted on the vehicle 1, and adds the right signal of the stereo signal and the left signal of the stereo signal. a first addition circuit for generating a monaural signal by using a first addition circuit and outputting the generated monaural signal as a first addition signal; As a signal, a third amplifier that outputs to the right rear speaker and the left rear speaker mounted on the vehicle 1 amplifies the input first addition signal and outputs the amplified first addition signal as a second addition output signal. and a fourth amplifier for outputting to the center speaker mounted on the vehicle 1 as.

According to this invention, sound image localization can be improved for all seats in a vehicle.

FIG. 1 is a block diagram showing an example of a main part of a configuration of an in-vehicle acoustic system to which an in-vehicle amplifier device according to Embodiment 1 is applied. FIG. 2 is a block diagram showing an example of a main part of the configuration of the vehicle-mounted amplifier device according to the first embodiment.

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

Embodiment 1.
A configuration of an in-vehicle acoustic system 10 to which an in-vehicle amplifier device 100 according to Embodiment 1 is applied will be described with reference to FIG.
A vehicle-mounted amplifier device 100 according to Embodiment 1 will be described below as being applied to a vehicle-mounted audio system 10 mounted on a vehicle 1 as an example.
FIG. 1 is a block diagram showing an example of a main part of the configuration of an in-vehicle acoustic system 10 to which an in-vehicle amplifier device 100 according to Embodiment 1 is applied.
The in-vehicle acoustic system 10 includes a front right speaker 11 , a front left speaker 12 , a rear right speaker 13 , a rear left speaker 14 , a center speaker 15 , a reproduction device 16 , and an in-vehicle amplifier device 100 .

The right front speaker 11 is a speaker arranged on the right front side inside the vehicle 1 .
The left front speaker 12 is a speaker arranged on the left front inside the vehicle 1 .
The right rear speaker 13 is a speaker arranged on the right rear side inside the vehicle 1 .
The left rear speaker 14 is a speaker arranged on the left rear inside the vehicle 1 .
The center speaker 15 is a speaker arranged in front inside the vehicle 1 . Specifically, for example, the center speaker 15 is arranged inside the vehicle 1 between the right front speaker 11 and the left front speaker 12 .

The playback device 16 outputs an audio signal. The playback device 16, for example, CD (Compact Disc), DVD (Digital Versatile Disc), HDD (Hard Disk Drive), USB (Universal Serial Bus) flash drive, SD memory card or other storage media such as audio The data is decoded, and the decoded audio data is output as an audio signal. Further, for example, the playback device 16 may demodulate received radio waves such as FM radio broadcasts or AM radio broadcasts, and output the demodulated radio waves as audio signals.
In the following description, it is assumed that the audio signal output by the playback device 16 is a stereo signal having a right signal and a left signal.
An audio signal output by the reproducing device 16 is input to the in-vehicle amplifier device 100 .

The in-vehicle amplifier device 100 is connected to the front right speaker 11, the front left speaker 12, the rear right speaker 13, the rear left speaker 14, and the center speaker 15, respectively.
The in-vehicle amplifier device 100 receives a stereo signal, which is an audio signal output by the reproduction device 16, and outputs sounds from each of the right front speaker 11, the left front speaker 12, the right rear speaker 13, the left rear speaker 14, and the center speaker 15. Output signals for outputting are output to the right front speaker 11, the left front speaker 12, the right rear speaker 13, the left rear speaker 14, and the center speaker 15, respectively.
Referring to FIG. 2, the configuration of vehicle-mounted amplifier device 100 according to the first embodiment will be described.
FIG. 2 is a block diagram showing an example of a main part of the configuration of the vehicle-mounted amplifier device 100 according to Embodiment 1. As shown in FIG.

The vehicle-mounted amplifier device 100 includes a first amplifier 101 , a second amplifier 102 , a third amplifier 103 , a fourth amplifier 104 and a first adder circuit 111 .
In addition to the configuration described above, the vehicle-mounted amplifier device 100 includes a connection line 106, a first delay circuit 121, a second delay circuit 122, a separation circuit 131, a second addition circuit 112, a first subtraction circuit 141, and a second subtraction circuit. 142, the first attenuation circuit 151, the third addition circuit 113, the third delay circuit 123, the second attenuation circuit 152, the fourth addition circuit 114, or the like.
Further, the vehicle-mounted amplifier device 100 may include equalizers 171, 172, 173, and 174 configured by filters such as IIR (Infinite Impulse Response) filters or FIR (Finite Impulse Response) filters. good.

As an example, the vehicle-mounted amplifier device 100 according to the first embodiment includes a first amplifier 101, a second amplifier 102, a third amplifier 103, a fourth amplifier 104, a first adding circuit 111, a connection line 106, and a first delay circuit. 121, second delay circuit 122, separation circuit 131, second addition circuit 112, second subtraction circuit 142, first attenuation circuit 151, third addition circuit 113, third delay circuit 123, second attenuation circuit 152, fourth An adder circuit 114 and equalizers 171, 172, 173 and 174 will be described.

The first amplifier 101 amplifies the right signal of the stereo signal. The first amplifier 101 outputs the amplified right signal to the front right speaker 11 mounted on the vehicle 1 as a right output signal.
The second amplifier 102 amplifies the left signal of the stereo signal. The second amplifier 102 outputs the amplified left side signal to the left front speaker 12 mounted on the vehicle 1 as a left side output signal.
The first adder circuit 111 adds the right stereo signal and the left stereo signal to generate a monaural signal. The first addition circuit 111 outputs the generated monaural signal as a first addition signal.
The third amplifier 103 amplifies the input first addition signal. The third amplifier 103 outputs the amplified first addition signal to the right rear speaker 13 and the left rear speaker 14 mounted on the vehicle 1 as a first addition output signal.
The fourth amplifier 104 amplifies the inputted first addition signal. The fourth amplifier 104 outputs the amplified first addition signal to the center speaker 15 mounted on the vehicle 1 as a second addition output signal.

With this configuration, the sound output from the center speaker 15 is monaural sound obtained by adding the right stereo signal and the left stereo signal. The sounds output from the rear right speaker 13 and the rear left speaker 14 are both monaural sounds obtained by adding the right stereo signal and the left stereo signal. Monaural sound, which is the sum of the right stereo signal and the left stereo signal, is closer to the frequency band of a person's singing voice than the difference signal between the right stereo signal and the left stereo signal. It will contain a lot of corresponding midrange.
When the sound output from the rear right speaker 13 and the rear left speaker 14 is monaural sound obtained by adding the right signal of the stereo signal and the left signal of the stereo signal, the sound output from the rear right speaker 13 and the rear left speaker 14 is obtained. A middle sound range corresponding to the frequency band of a person's singing voice can be made to float in the area between them, and sticking of a sound image to the rear right speaker 13 or the rear left speaker 14 in the rear seat can be suppressed.

When the monaural sound is simultaneously output from the center speaker 15, the rear right speaker 13, and the rear left speaker 14, the monaural sound obtained by adding the right signal of the stereo signal and the left signal of the stereo signal is a human singing voice. , the sound heard in the front seats is localized in the front as if singing in front of the eyes.
Therefore, sound image localization in the front seats is good.

Further, in the rear seat, since the center speaker 15 outputs a sound containing a large amount of middle sound, the sound image of the sound in the middle sound can be clearly localized in front of or above the rear seat.
Therefore, since it sounds as if a person is speaking in front of the rear seat, sound image localization in the rear seat is good.
That is, with the configuration as described above, sound image localization in all seats is improved.

The in-vehicle amplifier device 100 may include equalizers 171 , 172 , 173 , and 174 .
The equalizer 171 is a circuit for changing the frequency characteristics of the right signal of the stereo signal amplified by the first amplifier 101 . That is, the equalizer 171 changes the sound quality of the sound output from the front right speaker 11 to a desired sound quality.
When the vehicle-mounted amplifier device 100 includes the equalizer 171, the first amplifier 101 amplifies the right side signal of the stereo signal after changing the frequency characteristics output by the equalizer 171. FIG.
The equalizer 172 is a circuit for changing the frequency characteristics of the left signal of the stereo signal amplified by the second amplifier 102 . That is, the equalizer 172 changes the sound quality of the sound output from the left front speaker 12 to a desired sound quality.
When the in-vehicle amplifier device 100 includes the equalizer 172 , the second amplifier 102 amplifies the left side signal of the stereo signal after changing the frequency characteristics output by the equalizer 172 .

The equalizer 173 is a circuit for changing frequency characteristics of the first addition signal amplified by the third amplifier 103 . That is, the equalizer 173 changes the sound quality of the sound output from the right rear speaker 13 and the left rear speaker 14 to a desired sound quality.
When the vehicle-mounted amplifier device 100 includes the equalizer 173, the third amplifier 103 amplifies the first addition signal output by the equalizer 173 after changing the frequency characteristic.

The equalizer 174 is a circuit for changing the frequency characteristics of the first addition signal amplified by the fourth amplifier 104 . That is, the equalizer 174 changes the sound quality of the sound output from the center speaker 15 to a desired sound quality.
When vehicle-mounted amplifier device 100 includes equalizer 174 , fourth amplifier 104 amplifies the first addition signal after changing the frequency characteristics output by equalizer 174 .

In addition to the first amplifier 101, the second amplifier 102, the third amplifier 103, the fourth amplifier 104, and the first adding circuit 111, the vehicle-mounted amplifier device 100 may include a connection line 106. good.
The connection line 106 is a line for connecting the right rear speaker 13 and the left rear speaker 14 in series.
As shown in FIG. 2 , when vehicle-mounted amplifier device 100 includes connection line 106 , third amplifier 103 is connected in series to right rear speaker 13 and left rear speaker 14 via connection line 106 .

In-vehicle speakers have a predetermined resistance value such as 4 Ω (ohms), so by configuring in this manner, the strength of the sound output from the right rear speaker 13 and the left rear speaker 14 can be adjusted. The sum is reduced by about 6 dB (decibels) compared to the strength of the sound output from the center speaker 15 .
Therefore, since the sound from the front is heard louder than the sound from the rear, the sound heard in the front seat is localized to the front as if singing in front of the passenger. In particular, the monaural sound obtained by adding the right side signal of the stereo signal and the left side signal of the stereo signal contains a lot of mid-range frequencies corresponding to the frequency range of a person's singing voice, etc. It is localized forward as if singing in a song. Therefore, in the front seat, sound image localization in the front seat is good.
In addition, in the rear seats, the center speaker 15 outputs sound containing a large amount of the middle range, and the volume of the sound output from the right rear speaker 13 and the left rear speaker 14 is higher than that of the sound output from the center speaker 15. Since it is small compared to the volume, it is possible to clearly localize the sound image of sounds in the middle range in front of or above the rear seat. Therefore, it sounds as if a person in the rear seat is uttering a voice in front of or in front of the eyes, so sound image localization in the rear seat is good.
That is, with the configuration as described above, sound image localization in all seats is improved.

The vehicle-mounted amplifier device 100 includes a first delay circuit 121 in addition to the above-described first amplifier 101, second amplifier 102, third amplifier 103, fourth amplifier 104, and first adder circuit 111. can be
The first delay circuit 121 delays the input first addition signal with respect to the right signal amplified by the first amplifier 101 or the left signal amplified by the second amplifier 102 by a first predetermined period.
As shown in FIG. 2, when the vehicle-mounted amplifier device 100 includes the first delay circuit 121, the third amplifier 103 amplifies the first addition signal after being delayed by the first delay circuit 121 for the first predetermined period. configured to The first predetermined period of time is a predetermined period of time, such as 15 milliseconds. 15 milliseconds is merely an example, and the first predetermined period may be longer than 15 milliseconds or shorter than 15 milliseconds.
When the driver's seat is on the right side of the direction in which the vehicle 1 moves forward, as shown in FIG. The first addition signal is delayed by a first predetermined period with respect to the right signal amplified by the first amplifier 101 so that the delayed sound is output from the rear right speaker 13 and the rear left speaker 14 . The first delay circuit 121 responds to the left signal amplified by the second amplifier 102 when the driver's seat is on the right side of the vehicle 1 as shown in FIG. may be delayed by a first predetermined period.

With this configuration, the sounds output from the rear right speaker 13 and the rear left speaker 14 are delayed by a minute period with respect to the sound output from the reference speaker. When the sounds output from two speakers are shifted by a minute period, the position of the sound image localization formed between the two speakers can be moved. Therefore, the sound output from the right rear speaker 13 and the left rear speaker 14 is delayed by a minute period with respect to the sound output from the reference speaker, so that the sound heard in all the seats is directly in front of the driver. Forward localization as if singing.
In particular, monaural sound, which is the sum of the right stereo signal and the left stereo signal, contains a large amount of the mid-range, which corresponds to the frequency range of human singing, so the sound that can be heard in all seats is directly in front of you. Forward localization as if singing.
Therefore, in all the seats, it sounds as if a person is uttering a voice in front of them, so the sound image localization in all the seats is good.

Further, in the in-vehicle amplifier device 100, when the driver's seat is on the right side in the direction in which the vehicle 1 moves forward as shown in FIG. The right signal may be delayed with respect to the left signal amplified by the second amplifier 102 by a predetermined period of time, such as 10 milliseconds. With this configuration, in the driver's seat, the sound output from the right front speaker 11 close to the driver's seat is synchronized with the sound output from the left front speaker 12, and sound image localization in the driver's seat is improved. Become.
For example, the vehicle-mounted amplifier device 100 is configured to delay the right signal amplified by the first amplifier 101 with respect to the left signal amplified by the second amplifier 102 by 10 milliseconds. is delayed by the first delay circuit 121 with respect to the left signal amplified by the second amplifier 102 by 15 milliseconds, the first addition signal is amplified by the right signal. can be delayed by 5 milliseconds.

In the above description, the case where the driver's seat is located on the right side in the direction in which the vehicle 1 moves forward has been described, but the case where the driver's seat is located in the left side in the direction in which the vehicle 1 moves forward is the same. Therefore, the description is omitted.
In addition, although the vehicle-mounted amplifier device 100 shown in FIG. 1 is configured such that the first delay circuit 121 delays the signal output from the equalizer 173 as an example, it is not limited to this. For example, the vehicle-mounted amplifier device 100 may be configured to input the signal output from the first delay circuit 121 to the equalizer 173 and input the signal output from the equalizer 173 to the third amplifier 103 .

In addition to the first amplifier 101, the second amplifier 102, the third amplifier 103, the fourth amplifier 104, the first addition circuit 111, and the first delay circuit 121, the vehicle-mounted amplifier device 100 includes a second delay circuit. 122 may be provided.
The second delay circuit 122 delays the input first addition signal with respect to the right signal amplified by the first amplifier 101 or the left signal amplified by the second amplifier 102 by a second predetermined period shorter than the first predetermined period. delay for a period of time.
As shown in FIG. 2, when the vehicle-mounted amplifier device 100 includes the second delay circuit 122, the fourth amplifier 104 amplifies the first addition signal after the second delay circuit 122 has delayed it for the second predetermined period. configured to The second predetermined period of time is a predetermined period of time, such as 5 milliseconds. 5 milliseconds is merely an example, and the second predetermined period may be longer than 5 milliseconds or shorter than 5 milliseconds as long as it is shorter than the first predetermined period.
When the driver's seat is on the right side in the direction in which the vehicle 1 moves forward, as shown in FIG. The first addition signal is delayed by a second predetermined period with respect to the right signal amplified by the first amplifier 101 so that the delayed sound is output from the center speaker 15 .

With this configuration, the sound output from the right front speaker 11 close to the driver's seat is synchronized with the sound output from the center speaker 15, so that sound image localization in the driver's seat is good. Become.
Further, since the second predetermined period is shorter than the first predetermined period, the sound output from the rear right speaker 13 and the rear left speaker 14 is delayed by a minute period with respect to the sound output from the center speaker 15. . The voices output from the rear right speaker 13 and the rear left speaker 14 are delayed by a minute period with respect to the voice output from the center speaker 15, so that the voices heard in all seats are singing in front of the eyes. forward localization.
In particular, monaural sound, which is the sum of the right stereo signal and the left stereo signal, contains a large amount of the mid-range, which corresponds to the frequency range of human singing, so the sound that can be heard in all seats is directly in front of you. Forward localization as if singing.
Therefore, in all the seats, it sounds as if a person is uttering a voice in front of them, so the sound image localization in all the seats is good.

Since the same applies to the case where the driver's seat is on the left side in the direction in which the vehicle 1 moves forward, a description thereof will be omitted.
In addition, although the vehicle-mounted amplifier device 100 shown in FIG. 1 is configured such that the second delay circuit 122 delays the signal output from the equalizer 174 as an example, the present invention is not limited to this. For example, the vehicle-mounted amplifier device 100 may be configured to input the signal output from the second delay circuit 122 to the equalizer 174 and input the signal output from the equalizer 174 to the fourth amplifier 104 .

In addition to the above-described first amplifier 101, second amplifier 102, third amplifier 103, fourth amplifier 104, and first addition circuit 111, the vehicle-mounted amplifier device 100 includes a separation circuit 131 and a second addition circuit 112. may be provided.
The separating circuit 131 separates the middle range signal from the input first addition signal, generates a separated signal including part of the separated middle range signal, and outputs the generated separated signal. The separation circuit 131 is configured by, for example, a band-pass filter that passes the midrange signal. Specifically, for example, the separation circuit 131 extracts the middle range signal from the first addition signal, and attenuates the extracted middle range signal by a predetermined ratio to generate the separation signal.
The second addition circuit 112 adds the input separation signal to the input first addition signal.
As shown in FIG. 2, when the vehicle-mounted amplifier device 100 includes the separating circuit 131 and the second adding circuit 112, the fourth amplifier 104 outputs the first added signal after the second adding circuit 112 adds the separated signals. configured to amplify the

With this configuration, the sound output from the center speaker 15 has a middle range corresponding to the frequency band of human singing, etc., compared to the sound output from the rear right speaker 13 and the rear left speaker 14. The sound has a large proportion of frequency components. Therefore, the middle range corresponding to the frequency band of a person's singing voice can be heard better from the front.
Therefore, in all the seats, it sounds as if a person is uttering a voice in front of them, so the sound image localization in all the seats is good.

In addition to the above-described first amplifier 101, second amplifier 102, third amplifier 103, fourth amplifier 104, and first addition circuit 111, the vehicle-mounted amplifier device 100 includes a separation circuit 131 and a first subtraction circuit 141. may be provided.
Since the separation circuit 131 has been described above, the description thereof is omitted.
The first subtraction circuit 141 subtracts the input separation signal from the input first addition signal.
As shown in FIG. 2, when the vehicle-mounted amplifier device 100 includes the separating circuit 131 and the first subtracting circuit 141, the third amplifier 103 receives is configured to amplify the first summed signal of

With this configuration, the sound output from the rear right speaker 13 and the rear left speaker 14 can be the sounds of musical instruments, sound effects, and the like, while leaving frequency components in the middle range corresponding to the frequency band of human singing. Alternatively, the proportion of frequency components in the high range or low range corresponding to the frequency band of environmental sounds or the like is increased.
Therefore, in all seats, mid-range sounds, which correspond to the frequency range of human singing voices, can be heard clearly from the front, and high or low range sounds, which correspond to the frequency ranges of musical instrument sounds, sound effects, and environmental sounds, etc. sound will be heard better from behind.
Therefore, sound image localization is good in all seats because it sounds as if a person is uttering a voice in front while enhancing the sense of presence.

In addition to the above-described first amplifier 101, second amplifier 102, third amplifier 103, fourth amplifier 104, and first addition circuit 111, the vehicle-mounted amplifier device 100 includes a second subtraction circuit 142 and a first attenuation circuit. 151 and the third addition circuit 113 may be provided.
The second subtraction circuit 142 generates a difference signal between the right signal of the stereo signal and the left signal of the stereo signal, and outputs the generated difference signal as a first difference signal.
The first attenuation circuit 151 attenuates the input first difference signal by a predetermined ratio and outputs the attenuated first difference signal as a second difference signal. The predetermined percentage is, for example, 50%. 50% (percentage) is only an example, and the predetermined ratio may be a ratio larger than 50% or a ratio smaller than 50%.
The third adder circuit 113 adds the input second difference signal to the input first addition signal.
As shown in FIG. 2, when the vehicle-mounted amplifier device 100 includes the second subtraction circuit 142, the first attenuation circuit 151, and the third addition circuit 113, the third amplifier 103 is configured so that the third addition circuit 113 It is configured to amplify the first summed signal after summing the signals.

The difference signal between the right side signal of the stereo signal and the left side signal of the stereo signal is generally reduced in the middle range corresponding to the frequency band of a human singing voice, etc., and the sound of musical instruments, sound effects, environmental sounds, etc. It is a signal that includes many high-pitched or low-pitched sounds. Therefore, the sounds output from the right rear speaker 13 and the left rear speaker 14 are in a high range corresponding to the frequency band of musical instrument sounds, effect sounds, environmental sounds, etc. compared to the sound output from the center speaker 15. Or, it becomes a sound with a large proportion of frequency components in the low range.

With this configuration, the sound output from the rear right speaker 13 and the rear left speaker 14 can be the sounds of musical instruments, sound effects, and the like, while leaving frequency components in the middle range corresponding to the frequency band of human singing. Alternatively, the proportion of frequency components in the high range or low range corresponding to the frequency band of environmental sounds or the like is increased.
Therefore, in all seats, mid-range sounds corresponding to the frequency range of human singing voices can be heard well from the front, and high-range or low-range sounds corresponding to the frequency range of musical instrument sounds, sound effects, or environmental sounds Sound will be heard better from behind.
Therefore, sound image localization is good in all seats because it sounds as if a person is uttering a voice in front while enhancing the sense of presence.

The vehicle-mounted amplifier device 100 includes the first amplifier 101, the second amplifier 102, the third amplifier 103, the fourth amplifier 104, the first addition circuit 111, the second subtraction circuit 142, the first attenuation circuit 151, and the first A third delay circuit 123 may be provided in addition to the 3-adder circuit 113 .
Since the second subtraction circuit 142, the first attenuation circuit 151, and the third addition circuit 113 have been described above, the description thereof will be omitted.
The third delay circuit 123 delays the input second difference signal by a third predetermined period. The third predetermined period of time is a predetermined period of time, such as 5 milliseconds. 5 milliseconds is merely an example, and the third predetermined period may be longer than 5 milliseconds or shorter than 5 milliseconds.
As shown in FIG. 2, when the vehicle-mounted amplifier device 100 includes the third delay circuit 123, the third addition circuit 113 delays the input first addition signal by the third predetermined period. The third amplifier 103 is configured to amplify the first sum signal after the third summing circuit 113 has added the second difference signals.

With this configuration, the sounds output from the right rear speaker 13 and the left rear speaker 14 include frequency components in the middle range corresponding to the frequency band of human singing voices, etc., sounds of musical instruments, sound effects, or High or low frequency components corresponding to the frequency bands of environmental sounds, etc. remain as reverberation, while high or low frequency components corresponding to the frequency bands of musical instrument sounds, sound effects, or environmental sounds remain as reverberation. sounds like
Therefore, in all seats, people's singing voices can be heard from the front, sounds of musical instruments, sound effects, environmental sounds, etc. can be heard from the rear, and reverberations of musical instruments, sound effects, environmental sounds, etc. become audible.
Therefore, sound image localization is good in all seats because it sounds as if a person is uttering a voice in front while enhancing the sense of presence.

The vehicle-mounted amplifier device 100 includes the first amplifier 101, the second amplifier 102, the third amplifier 103, the fourth amplifier 104, the first addition circuit 111, the second subtraction circuit 142, the first attenuation circuit 151, and the third addition circuit. In addition to the circuit 113 and the third delay circuit 123, the second attenuation circuit 152 and the fourth addition circuit 114 may be provided.
Since the second subtractor circuit 142, the first attenuator circuit 151, the third adder circuit 113, and the third delay circuit 123 have been described above, description thereof will be omitted.
The second attenuation circuit 152 outputs an attenuation signal obtained by attenuating the input signal by a predetermined ratio. The predetermined percentage is, for example, 50%. 50% (percentage) is only an example, and the predetermined ratio may be a ratio larger than 50% or a ratio smaller than 50%.

The fourth addition circuit 114 adds the second difference signal output from the first attenuation circuit 151 and the attenuation signal output from the second attenuation circuit 152, and uses the signal after the addition as the fourth addition signal for the third delay. Output to circuit 123 .
The third delay circuit 123 delays the fourth addition signal output from the fourth addition circuit 114 by a third predetermined period, and outputs the delayed fourth addition signal as a third delay signal.
That is, the second attenuation circuit 152 attenuates the third delay signal output from the third delay circuit 123 by a predetermined ratio, and outputs the signal after attenuation to the fourth addition circuit 114 as an attenuation signal.
A reverberation signal of the second difference signal is generated by the third delay circuit 123, the second attenuation circuit 152, and the fourth addition circuit 114. FIG.
As shown in FIG. 2, when the vehicle-mounted amplifier device 100 includes the second attenuation circuit 152 and the fourth addition circuit 114, the third addition circuit 113 causes the input first addition signal to The output third delay signals are added, and the third amplifier 103 is configured to amplify the first addition signal after the third addition circuit 113 has added the third delay signals.

With this configuration, the sounds output from the right rear speaker 13 and the left rear speaker 14 include frequency components in the middle range corresponding to the frequency band of human singing voices, etc., sounds of musical instruments, sound effects, or High or low frequency components corresponding to the frequency bands of environmental sounds, etc. remain as reverberation, while high or low frequency components corresponding to the frequency bands of musical instrument sounds, sound effects, or environmental sounds remain as reverberation. sounds like
Therefore, in all seats, people's singing voices can be heard from the front, sounds of musical instruments, sound effects, environmental sounds, etc. can be heard from the rear, and reverberations of musical instruments, sound effects, environmental sounds, etc. become audible.
Therefore, sound image localization is good in all seats because it sounds as if a person is uttering a voice in front while enhancing the sense of presence.

As described above, the in-vehicle amplifier device 100 amplifies the right side signal of the stereo signal and outputs the amplified right side signal as the right side output signal to the right front speaker 11 mounted on the vehicle 1 and the first amplifier 101 . , a second amplifier 102 that amplifies the left signal of the stereo signal and outputs the amplified left signal as a left output signal to the front left speaker 12 mounted on the vehicle 1; the right signal of the stereo signal; a first addition circuit 111 for generating a monaural signal by adding the left side signal and outputting the generated monaural signal as a first addition signal; The third amplifier 103 outputs the addition signal as a first addition output signal to the right rear speaker 13 and the left rear speaker 14 mounted on the vehicle 1, and amplifies the input first addition signal to obtain a signal after amplification. and a fourth amplifier 104 that outputs the first addition signal to a center speaker 15 mounted on the vehicle 1 as a second addition output signal.
By configuring in this way, sound image localization can be improved for all seats in the vehicle 1 .

In addition to the first amplifier 101, the second amplifier 102, the third amplifier 103, the fourth amplifier 104, and the first addition circuit 111, the vehicle-mounted amplifier device 100 includes a rear right speaker 13 and a rear left speaker. The third amplifier 103 is connected in series to the right rear speaker 13 and the left rear speaker 14 via the connection line 106 .
By configuring in this way, sound image localization can be improved for all seats in the vehicle 1 .

In addition to the first amplifier 101, the second amplifier 102, the third amplifier 103, the fourth amplifier 104, and the first addition circuit 111, the vehicle-mounted amplifier device 100 receives the input first addition signal. , a first delay circuit 121 for delaying the right signal amplified by the first amplifier 101 or the left signal amplified by the second amplifier 102 by a first predetermined period. 121 to amplify the first summed signal after delaying it by a first predetermined period.
By configuring in this way, sound image localization can be improved for all seats in the vehicle 1 .

In addition to the first amplifier 101, the second amplifier 102, the third amplifier 103, the fourth amplifier 104, the first addition circuit 111, and the first delay circuit 121, the vehicle-mounted amplifier device 100 has an input The second delay circuit 122 delays the first addition signal by a second predetermined period shorter than the first predetermined period with respect to the right signal amplified by the first amplifier 101 or the left signal amplified by the second amplifier 102. The third amplifier 103 amplifies the first addition signal after being delayed by the first delay circuit 121 for the first predetermined period, and the fourth amplifier 104 delays the second delay circuit 122 for the second predetermined period. It is configured to amplify the first summed signal after being delayed.
By configuring in this way, sound image localization can be improved for all seats in the vehicle 1 .

In addition to the first amplifier 101, the second amplifier 102, the third amplifier 103, the fourth amplifier 104, and the first adder circuit 111, the vehicle-mounted amplifier device 100 has a A separation circuit 131 that separates the midrange signal among them, generates a separated signal containing a part of the separated midrange signal, and outputs the generated separated signal, a second summing circuit 112 for summing the signals, and the fourth amplifier 104 is configured to amplify the first summed signal after the second summing circuit 112 sums the separated signals.
By configuring in this way, sound image localization can be improved for all seats in the vehicle 1 .

In addition to the first amplifier 101, the second amplifier 102, the third amplifier 103, the fourth amplifier 104, and the first adder circuit 111, the vehicle-mounted amplifier device 100 has a A separation circuit 131 that separates the midrange signal among them, generates a separated signal containing a part of the separated midrange signal, and outputs the generated separated signal, and the input first added signal, the input separation a first subtracting circuit 141 for subtracting the signals, and the third amplifier 103 is configured to amplify the first summed signal after the second summing circuit 112 has subtracted the separated signals.
By configuring in this way, sound image localization can be improved for all seats in the vehicle 1 .

In addition to the first amplifier 101, the second amplifier 102, the third amplifier 103, the fourth amplifier 104, and the first addition circuit 111, the vehicle-mounted amplifier device 100 includes the right side signal of the stereo signal and the stereo signal. A second subtraction circuit 142 for generating a difference signal from the left side signal of the signal and outputting the generated difference signal as a first difference signal; a first attenuation circuit 151 for outputting the first difference signal as a second difference signal; and a third addition circuit 113 for adding the input second difference signal to the input first addition signal. The amplifier 103 is configured to amplify the first addition signal after the third addition circuit 113 has added the second difference signal.
By configuring in this way, sound image localization can be improved for all seats in the vehicle 1 .

Further, the vehicle-mounted amplifier device 100 includes the above-described first amplifier 101, second amplifier 102, third amplifier 103, fourth amplifier 104, first addition circuit 111, second subtraction circuit 142, first attenuation circuit 151, and , in addition to the third adder circuit 113, a third delay circuit 123 for delaying the input second difference signal by a third predetermined period is provided. The third delay circuit 123 adds the second difference signal delayed by the third predetermined period, and the third amplifier 103 amplifies the first addition signal after the third addition circuit 113 adds the second difference signal. configured to
By configuring in this way, sound image localization can be improved for all seats in the vehicle 1 .

Further, the vehicle-mounted amplifier device 100 includes the first amplifier 101, the second amplifier 102, the third amplifier 103, the fourth amplifier 104, the first addition circuit 111, the second subtraction circuit 142, the first attenuation circuit 151, the first In addition to the 3-adder circuit 113 and the third delay circuit 123, a second attenuation circuit 152 that outputs an attenuation signal obtained by attenuating the input signal by a predetermined ratio, and a second difference output from the first attenuation circuit 151 and a fourth addition circuit 114 that adds the signal and the attenuation signal output from the second attenuation circuit 152 and outputs the signal after the addition as a fourth addition signal. The fourth addition signal output by the circuit 114 is delayed by a third predetermined period, and the delayed fourth addition signal is output as a third delay signal. and the third delay signal output from the third delay circuit 123, and the third amplifier 103 amplifies the first addition signal after the addition of the third delay signal by the third addition circuit 113. .
By configuring in this way, sound image localization can be improved for all seats in the vehicle 1 .

It should be noted that, within the scope of the invention, any component of the embodiment can be modified, or any component can be omitted from the embodiment.

Reference Signs List 1 vehicle, 10 in-vehicle acoustic system, 11 right front speaker, 12 left front speaker, 13 right rear speaker, 14 left rear speaker, 15 center speaker, 16 playback device, 100 in-vehicle amplifier device, 101 first amplifier, 102 second amplifier , 103 third amplifier, 104 fourth amplifier, 106 connection line, 111 first addition circuit, 112 second addition circuit, 113 third addition circuit, 114 fourth addition circuit, 121 first delay circuit, 122 second delay circuit , 123 third delay circuit, 131 separation circuit, 141 first subtraction circuit, 142 second subtraction circuit, 151 first attenuation circuit, 152 second attenuation circuit, 171, 172, 173, 174 equalizer.

Claims (8)

a first amplifier that amplifies a right side signal of a stereo signal and outputs the amplified right side signal as a right side output signal to a right front speaker mounted on a vehicle;
a second amplifier that amplifies the left signal of the stereo signal and outputs the amplified left signal as a left output signal to a left front speaker mounted on the vehicle;
a first addition circuit that adds the right signal of the stereo signal and the left signal of the stereo signal to generate a monaural signal, and outputs the generated monaural signal as a first addition signal;
a third amplifier that amplifies the input first addition signal and outputs the amplified first addition signal as a first addition output signal to a right rear speaker and a left rear speaker mounted on the vehicle; ,
a fourth amplifier that amplifies the input first addition signal and outputs the amplified first addition signal as a second addition output signal to a center speaker mounted on the vehicle;
a separation circuit that separates a midrange signal from the input first addition signal, generates a separated signal that includes a part of the separated midrange signal, and outputs the generated separated signal;
a second addition circuit that adds the input separation signal to the input first addition signal;
with
The fourth amplifier amplifies the first addition signal after the second addition circuit has added the separated signals.
An in-vehicle amplifier device characterized by: a first amplifier that amplifies a right side signal of a stereo signal and outputs the amplified right side signal as a right side output signal to a right front speaker mounted on a vehicle;
a second amplifier that amplifies the left signal of the stereo signal and outputs the amplified left signal as a left output signal to a left front speaker mounted on the vehicle;
a first addition circuit that adds the right signal of the stereo signal and the left signal of the stereo signal to generate a monaural signal, and outputs the generated monaural signal as a first addition signal;
a third amplifier that amplifies the input first addition signal and outputs the amplified first addition signal as a first addition output signal to a right rear speaker and a left rear speaker mounted on the vehicle; ,
a fourth amplifier that amplifies the input first addition signal and outputs the amplified first addition signal as a second addition output signal to a center speaker mounted on the vehicle;
a separation circuit that separates a midrange signal from the input first addition signal, generates a separated signal that includes a part of the separated midrange signal, and outputs the generated separated signal;
a first subtraction circuit for subtracting the input separation signal from the input first addition signal;
with
The vehicle -mounted amplifier device, wherein the third amplifier amplifies the first addition signal after the first subtraction circuit subtracts the separation signal. a first amplifier that amplifies a right side signal of a stereo signal and outputs the amplified right side signal as a right side output signal to a right front speaker mounted on a vehicle;
a second amplifier that amplifies the left signal of the stereo signal and outputs the amplified left signal as a left output signal to a left front speaker mounted on the vehicle;
a first addition circuit that adds the right signal of the stereo signal and the left signal of the stereo signal to generate a monaural signal, and outputs the generated monaural signal as a first addition signal;
a third amplifier that amplifies the input first addition signal and outputs the amplified first addition signal as a first addition output signal to a right rear speaker and a left rear speaker mounted on the vehicle; ,
a fourth amplifier that amplifies the input first addition signal and outputs the amplified first addition signal as a second addition output signal to a center speaker mounted on the vehicle;
a subtraction circuit that generates a difference signal between the right signal of the stereo signal and the left signal of the stereo signal, and outputs the generated difference signal as a first difference signal;
a first attenuation circuit that attenuates the input first difference signal by a predetermined rate and outputs the attenuated first difference signal as a second difference signal;
a third addition circuit that adds the input second difference signal to the input first addition signal;
with
The vehicle-mounted amplifier device, wherein the third amplifier amplifies the first addition signal after the addition of the second difference signal by the third addition circuit. a third delay circuit for delaying the input second difference signal by a third predetermined period;
4. The third addition circuit adds the second difference signal after delaying the input first addition signal by the third predetermined period by the third delay circuit to the input first addition signal. An in-vehicle amplifier device as described. a second attenuation circuit that outputs an attenuation signal obtained by attenuating an input signal by a predetermined ratio;
a fourth addition circuit that adds the second difference signal output by the first attenuation circuit and the attenuation signal output by the second attenuation circuit and outputs the signal after the addition as a fourth addition signal;
with
the third delay circuit delays the fourth addition signal output from the fourth addition circuit by the third predetermined period, and outputs the delayed fourth addition signal as a third delay signal;
5. The in-vehicle amplifier device according to claim 4, wherein the third adder circuit adds the third delay signal output from the third delay circuit to the input first sum signal. a connection line that connects the rear right speaker and the rear left speaker in series;
The in-vehicle amplifier device according to any one of claims 1 to 5, wherein the third amplifier is connected in series to the rear right speaker and the rear left speaker via the connection line. . a first delay circuit for delaying the input first addition signal with respect to the right signal amplified by the first amplifier or the left signal amplified by the second amplifier by a first predetermined period;
The in-vehicle vehicle according to any one of claims 1 to 5, wherein the third amplifier amplifies the first addition signal after being delayed by the first delay circuit by the first predetermined period. amplifier device. The input first addition signal is delayed by a second predetermined period shorter than the first predetermined period with respect to the right signal amplified by the first amplifier or the left signal amplified by the second amplifier. a second delay circuit that causes
8. The vehicle-mounted amplifier device according to claim 7 , wherein said fourth amplifier amplifies said first addition signal after being delayed by said second delay circuit by said second predetermined period.

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