阅读说明：本技术 车载音响系统及具有该车载音响系统的车辆 (Vehicle-mounted sound system and vehicle with same ) 是由 平野克也 疋田智一 中岛崇量 于 2021-05-27 设计创作，主要内容包括：不增加车载音响系统的声道数、且不追加重低音用的放大器,输出从重低音频至高频为止的音。音响系统(1A)具有向至扬声器(10－1A)的信号路径(SL1)输出音信号(S1a)的放大器(310－1)、向至扬声器(10－2A)的信号路径(SL2)输出音信号(S2a)的放大器(310－2)、向扬声器(10－3A)及扬声器(10－5)输出音信号(S3a)的放大器(310－3)和向扬声器(10－4A)及扬声器(10－6)输出音信号(S4a)的放大器(310－4),在音响系统(1A)中,向双音圈的扬声器(10－7)经由从信号路径(SL1)分支出的信号路径(SL5)而赋予音信号(S1a),经由从信号路径(SL2)分支出的信号路径(SL6)而赋予音信号(S2a)。(The vehicle-mounted audio system outputs sounds from a heavy bass sound frequency to a high frequency sound frequency without increasing the number of channels and without adding an amplifier for heavy bass sounds. An acoustic system (1A) includes an amplifier (310-1) that outputs a sound signal (S1A) to a signal path (SL1) to a speaker (10-1A), an amplifier (310-2) that outputs a sound signal (S2A) to a signal path (SL2) to a speaker (10-2A), an amplifier (310-3) that outputs a sound signal (S3A) to a speaker (10-3A) and a speaker (10-5), and an amplifier (310-4) that outputs a sound signal (S4A) to a speaker (10-4A) and a speaker (10-6), wherein in the acoustic system (1A), the sound signal (S1A) is given to a speaker (10-7) of a dual voice coil via a signal path (SL5) branched from the signal path (SL1), and the sound signal (S2 36 2A) is given via a signal path (SL6) branched from the signal path (SL 2).)

1. An in-vehicle sound system, comprising:

a 1 st amplifier for outputting the 1 st sound signal to a 1 st intermediate frequency speaker via a 1 st signal path;

a 2 nd amplifier for outputting the 2 nd sound signal to a 2 nd intermediate frequency speaker via a 2 nd signal path;

a 3 rd amplifier for outputting a 3 rd sound signal to the 1 st high-frequency speaker and the 1 st low-frequency speaker; and

a 4 th amplifier for outputting a 4 th sound signal to the 2 nd high-frequency speaker and the 2 nd low-frequency speaker,

in the in-vehicle audio system,

the 3 rd sound signal is input to the 1 st tweeter through a 3 rd signal path from the 3 rd amplifier to the 1 st tweeter,

the 4 th sound signal is input to the 2 nd tweeter through a 4 th signal path from the 4 th amplifier to the 2 nd tweeter,

the 1 st sound signal is input to a subwoofer through a 5 th signal path branched from the 1 st signal path,

the 1 st woofer is inputted with the 3 rd tone signal via a 6 th signal path branched from the 3 rd signal path,

the 4 th sound signal is input to the 2 nd low-frequency speaker via a 7 th signal path branched from the 4 th signal path,

the 1 st midrange speaker, the 1 st tweeter, and the 1 st woofer are provided on the same side of the vehicle on either right or left side,

the 2 nd midrange speaker, the 2 nd high-frequency speaker, and the 2 nd low-frequency speaker are provided on an opposite side of the left and right of the vehicle from the 1 st midrange speaker.

2. The car audio system according to claim 1,

the playback frequency band of the 1 st midrange speaker is expanded to a lower frequency side than the playback frequency band of the 1 st tweeter.

3. The car audio system according to claim 1 or 2,

a cutoff frequency is determined according to a lower limit frequency of a playback frequency band of the 1 st intermediate frequency speaker, and a 1 st filter that cuts off a signal having a frequency lower than the cutoff frequency is provided in a signal path from a branch point between the 1 st signal path and the 5 th signal path among the 1 st signal paths to the 1 st intermediate frequency speaker.

4. The car audio system according to any one of claims 1 to 3,

the 2 nd sound signal is also input to the subwoofer via an 8 th signal path branching from the 2 nd signal path,

the subwoofer has a 1 st voice coil connected to the 5 th signal path and a 2 nd voice coil connected to the 8 th signal path.

5. The car audio system according to any one of claims 1 to 4,

the reproduction band of the 1 st woofer is expanded to a low frequency side compared with the reproduction band of the 1 st midrange speaker,

the playback frequency band of the 2 nd woofer is expanded to a low frequency side compared with the playback frequency band of the 2 nd midrange speaker.

6. The car audio system according to claim 5,

the 1 st high-frequency speaker and the 1 st low-frequency speaker and the 2 nd high-frequency speaker and the 2 nd low-frequency speaker are disposed in front of the vehicle interior,

the 1 st midrange speaker, the 2 nd midrange speaker, and the subwoofer are disposed behind the vehicle cabin.

7. An in-vehicle sound system, comprising:

a 1 st amplifier for outputting the 1 st sound signal to a 1 st intermediate frequency speaker via a 1 st signal path;

a 2 nd amplifier for outputting the 2 nd sound signal to a 2 nd intermediate frequency speaker via a 2 nd signal path;

a 3 rd amplifier for outputting the 3 rd sound signal to the 1 st full range speaker via a 3 rd signal path; and

a 4 th amplifier outputting the 4 th tone signal to the 2 nd full range speaker through a 4 th signal path,

in the in-vehicle audio system,

the 1 st sound signal is input to a subwoofer through a 5 th signal path branched from the 1 st signal path,

the 1 st midrange speaker and the 1 st full-range speaker are provided on the same side of the vehicle,

the 2 nd midrange speaker and the 2 nd full-range speaker are provided on an opposite side of the left and right sides of the vehicle from the 1 st midrange speaker.

8. A vehicle having the in-vehicle sound system of any one of claims 1 to 7.

Technical Field

The present invention relates to a car audio system and a vehicle having the same.

Background

Patent document 1 discloses a technique for driving a woofer of a dual voice coil speaker by using an R signal input to a right tweeter and an L signal input to a left tweeter. Patent document 2 discloses a technique for driving woofers of a dual voice coil speaker by using an R signal input to a right full-range speaker and an L signal input to a left full-range speaker.

Patent document 1: japanese patent laid-open No. 2012-74780

Patent document 2: japanese patent No. 3153101

In an in-vehicle audio system for outputting musical sounds or the like to a vehicle interior of a vehicle such as a passenger vehicle, normally, woofers and tweeters provided on the front left and right sides and woofers and tweeters provided on the rear left and right sides are driven by a 4-channel amplifier. When a subwoofer is provided in addition to the woofers and tweeters on the front and rear sides, it is conceivable to drive these speakers by an amplifier of 5 channels or more or equal, or to use another amplifier independent of the 4-channel amplifier for driving the subwoofer. However, there is a problem that the cost increases in the system using an amplifier having 5 channels or more and the system using another amplifier for the bass.

In a system in which a woofer and a tweeter are driven as a set as disclosed in patent document 1, there is a possibility that high-frequency noise is generated. There is a demand for a car audio system to output bass frequencies at a large volume. Therefore, many woofers are driven using a tone signal clipped (clip) to the power supply voltage. At this time, the tone signal clipped to the power supply voltage is also input to the high tone speaker. Since the tweeter has a capability of outputting a high-frequency component, the high-frequency component generated by clipping is reproduced as high-frequency noise. Similarly, as in the technique disclosed in patent document 2, there is a possibility that high-frequency noise is generated even when a full-range speaker and a woofer are driven as a set.

Disclosure of Invention

The present invention has been made in view of the above-described problems, and an object of the present invention is to enable output of wide-band sound ranging from heavy bass to high frequencies without increasing the number of channels of a car audio system having a 4-channel amplifier and without adding an amplifier for heavy bass.

One embodiment of an in-vehicle audio system according to the present invention includes: a 1 st amplifier for outputting the 1 st sound signal to a 1 st intermediate frequency speaker via a 1 st signal path; a 2 nd amplifier for outputting the 2 nd sound signal to a 2 nd intermediate frequency speaker via a 2 nd signal path; a 3 rd amplifier for outputting a 3 rd sound signal to the 1 st high-frequency speaker and the 1 st low-frequency speaker; and a 4 th amplifier for outputting the 4 th sound signal to the 2 nd high-frequency speaker and the 2 nd low-frequency speaker. The 3 rd sound signal is input to the 1 st tweeter through a 3 rd signal path from the 3 rd amplifier to the 1 st tweeter. The 4 th sound signal is input to the 2 nd tweeter through a 4 th signal path from the 4 th amplifier to the 2 nd tweeter. The 1 st sound signal is input to a subwoofer through a 5 th signal path branched from the 1 st signal path. The 1 st woofer is inputted with the 3 rd sound signal via a 6 th signal path branched from the 3 rd signal path. The 4 th sound signal is input to the 2 nd low-band speaker via a 7 th signal path branched from the 4 th signal path. The 1 st midrange speaker, the 1 st tweeter, and the 1 st woofer are provided on the same side of the vehicle on either right or left side. The 2 nd midrange speaker, the 2 nd high-frequency speaker, and the 2 nd low-frequency speaker are provided on an opposite side of the left and right of the vehicle from the 1 st midrange speaker.

In addition, an aspect of the in-vehicle audio system according to the present invention includes: a 1 st amplifier for outputting the 1 st sound signal to a 1 st intermediate frequency speaker via a 1 st signal path; a 2 nd amplifier for outputting the 2 nd sound signal to a 2 nd intermediate frequency speaker via a 2 nd signal path; a 3 rd amplifier for outputting the 3 rd sound signal to the 1 st full range speaker via a 3 rd signal path; and a 4 th amplifier outputting the 4 th sound signal to the 2 nd full range speaker through a 4 th signal path. The 1 st sound signal is input to a subwoofer through a 5 th signal path branched from the 1 st signal path. The 1 st midrange speaker and the 1 st full-range speaker are provided on the same side of the vehicle on both right and left sides. The 2 nd midrange speaker and the 2 nd full-range speaker are provided on an opposite side of the left and right sides of the vehicle from the 1 st midrange speaker.

One aspect of the vehicle according to the present invention includes the in-vehicle audio system according to any one of the aspects described above.

Drawings

Fig. 1 is a diagram showing a configuration example of an acoustic system 1A according to an embodiment of the present invention.

Fig. 2 is a diagram showing an example of the arrangement of speakers 10-1A to 10-7 in a vehicle room CR of a vehicle C equipped with the acoustic system 1A.

Fig. 3 is a diagram showing an example of a frequency distribution of sound pressure measured at the front seat of the vehicle C having the acoustic system 1A.

Fig. 4 is a diagram showing an example of a frequency distribution of sound pressure measured at the rear seat of the vehicle C having the acoustic system 1A.

Fig. 5 is a diagram showing a configuration example of an acoustic system 1B according to modification 5.

Fig. 6 is a diagram showing a configuration example of an acoustic system 1C according to modification 6.

Detailed Description

Embodiments according to the present invention will be described below with reference to the drawings. In the drawings, the dimensions and scales of the respective portions are appropriately different from those in the actual case. The embodiments described below are suitable specific examples of the present invention. Therefore, the following embodiments are accompanied by various limitations that are technically preferable. However, the scope of the present invention is not limited to these embodiments unless otherwise specified in the following description.

1. Detailed description of the preferred embodiments

Fig. 1 is a diagram showing a configuration example of an acoustic system 1A according to an embodiment of the present invention. As shown in fig. 1, the acoustic system 1A includes a speaker 10-1A, a speaker 10-2A, a speaker 10-3A, a speaker 10-4A, a speaker 10-5, a speaker 10-6, a speaker 10-7, filters 20-1 to 20-4, and a driver 30 for driving the speaker 10-1A to the speaker 10-7, respectively. The acoustic system 1A is a vehicle-mounted acoustic system mounted on a vehicle such as a passenger car and configured to output musical sounds or the like into a vehicle interior of the vehicle. Speaker 10-1A, speaker 10-2A and speaker 10-7 are disposed behind the vehicle compartment. Speaker 10-3A, speaker 10-4A, speaker 10-5 and speaker 10-6 are disposed in front of the vehicle compartment. In addition, speaker 10-1A, speaker 10-3A and speaker 10-5 are disposed on the right side of the vehicle compartment. Speaker 10-2A, speaker 10-4A and speaker 10-6 are disposed on the left side of the vehicle compartment. Details of the arrangement of the speakers 10-1A to 10-7 will be described later.

Speakers 10-1A and 10-2A are midrange speakers (squawker). Speakers 10-3A and 10-4A are tweeters (tweeters). Speakers 10-5 and 10-6 are woofers (woofers). The loudspeaker 10-7 is a Subwoofer (Subwoofer). The reproduction band of the speaker 10-5 is expanded to the low frequency side as compared with the reproduction band of the speaker 10-3A. The broadcast frequency band is a frequency band in which a measured value of sound pressure is not reduced by 20db or more when a sound pressure at a position separated by 1m on the reference axis of the speaker is measured by applying a voltage corresponding to a sine wave of 1W to the input terminal of the speaker. The reproduction band of the speaker 10-5 and the reproduction band of the speaker 10-3A partially overlap. Specifically, the graph showing the reproduction band of the speaker 10-5 and the graph showing the reproduction band of the speaker 10-3A intersect each other in the vicinity of 2 to 4 kHz. The reproduction band of the speaker 10-6 is also expanded to the low frequency side as compared with the reproduction band of the speaker 10-4A. The playback frequency band of speaker 10-6 and the playback frequency band of speaker 10-4A partially overlap. The graph showing the reproduction band of the speaker 10-6 and the graph showing the reproduction band of the speaker 10-4A intersect each other in the vicinity of 2 to 4 kHz.

The playback frequency band of speaker 10-1A overlaps with a portion of the playback frequency band of speaker 10-3A and also overlaps with a portion of the playback frequency band of speaker 10-5. The reproduction band of the speaker 10-3A is expanded to a higher frequency side than the reproduction band of the speaker 10-1A. The reproduction band of the speaker 10-5 is expanded to the low frequency side as compared with the reproduction band of the speaker 10-1A. The graph showing the reproduction band of the speaker 10-1A and the graph showing the reproduction band of the speaker 10-5 intersect each other in the vicinity of 200 to 400 Hz. The playback frequency band of speaker 10-2A overlaps with a portion of the playback frequency band of speaker 10-4A and also overlaps with a portion of the playback frequency band of speaker 10-6. The reproduction band of the speaker 10-4A is expanded to a higher frequency side than the reproduction band of the speaker 10-2A. The reproduction band of the speaker 10-6 is expanded to the low frequency side as compared with the reproduction band of the speaker 10-2A. The graph showing the reproduction band of the speaker 10-2A and the graph showing the reproduction band of the speaker 10-6 intersect each other in the vicinity of 200 to 400 Hz.

Speaker 10-1A is an example of the first midrange speaker in the present invention. The speaker 10-2A is an example of the second mid-range speaker in the present invention. The speaker 10-3A is an example of the 1 st high-frequency speaker in the present invention. The speaker 10-4A is an example of the 2 nd high-frequency speaker in the present invention. The speaker 10-5 is an example of the 1 st woofer in the present invention. The speaker 10-6 is an example of the 2 nd low-frequency speaker in the present invention.

The playback frequency band of speaker 10-7 overlaps with a portion of the playback frequency band of speaker 10-5. The reproduction band of the speaker 10-7 is expanded to the low frequency side as compared with the reproduction band of the speaker 10-5. The graph showing the reproduction band of the speaker 10-7 and the graph showing the reproduction band of the speaker 10-5 intersect each other in the vicinity of 100 to 200 Hz. In addition, the playback frequency band of speaker 10-7 overlaps with the playback frequency band of speaker 10-6. The reproduction band of the speaker 10-7 is expanded to the low frequency side as compared with the reproduction band of the speaker 10-6. The graph showing the reproduction band of the speaker 10-7 and the graph showing the reproduction band of the speaker 10-6 intersect each other in the vicinity of 100 to 200 Hz. The speaker 10-7 is an example of a subwoofer that is responsible for playing bass audio.

A detailed illustration is omitted in fig. 1, but the speaker 10-7 is a dual voice coil speaker having 2 voice coils. A sound signal S1A is applied to one of 2 voice coils of the speaker 10-7 through a signal path SL5 branched from a signal path SL1, the signal path SL1 being a signal path from the driver 30 to the speaker 10-1A. The voice coil to which the sound signal S1a is applied via the signal path SL5 is an example of the 1 st voice coil in the present invention. Further, the sound signal S2A is applied to the other voice coil of the 2 voice coils of the speaker 10-7 through a signal path SL6 branched from a signal path SL2, the signal path SL2 being a signal path from the driver 30 to the speaker 10-2A. The voice coil to which the sound signal S2a is applied via the signal path SL6 is an example of the 2 nd voice coil in the present invention. In the present embodiment, since the speaker 10-7 is driven by two sound signals, i.e., the sound signal S1a and the sound signal S2a, the output sound pressure can be increased as compared with the case where the speaker 10-7 is driven by any one of the sound signals S1a and S2 a. If speaker 10-7 is a dual voice coil speaker, the efficiency may be reduced compared to the manner in which a single voice coil speaker is used as speaker 10-7. Since the speaker 10-7 of the present embodiment is a dual voice coil speaker, a circuit for generating monaural sound signals from the sound signal S1a and the sound signal S2a can be omitted.

The drive device 30 is provided on an instrument panel or the like of a vehicle on which the acoustic system 1A is mounted. The sound signals S1 to S4 are applied to the driving device 30 via a preamplifier or the like, not shown. The tone signals S1 to S4 are obtained by adjusting the volume and mixing the tone signals, such as the singing voice and the musical performance voice of the music piece. In the present embodiment, each of the tone signals S1 to S4 is a tone signal obtained by mixing a tone signal of a singing voice of a music piece and a tone signal of a musical performance voice. More specifically, the sound signals S1 and S3 are right channel sound signals in the case where the music piece is played in stereo. The sound signal S2 and the sound signal S4 are sound signals of the left channel in the case where the music piece is played in stereo. The tone signals S1 and S2 contain frequency components in a frequency band extending from the heavy bass frequencies to high frequencies. The tone signals S3 and S4 contain frequency components of a frequency band extending from bass frequencies to high frequencies. Note that the sound signals S1 to S4 may be all the same sound signals.

The driving device 30 is a 4-channel amplifier. The driving device 30 has amplifiers 310-1 to 310-4 for amplifying and outputting the sound signals S1 to S4. The amplifier 310-1 amplifies the tone signal S1 to a level suitable for speaker driving. Amplifier 310-1 outputs the amplified tone signal S1A to signal path SL1 to speaker 10-1A. Amplifier 310-1 is an example of the 1 st amplifier in the present invention. Signal path SL1 from amplifier 310-1 to speaker 10-1A is an example of signal path 1 in the present invention. The tone signal S1a is an example of the 1 st tone signal in the present invention. The signal path SL5 branched from the signal path SL1 to the speaker 10-7 is an example of the 5 th signal path in the present invention.

As shown in fig. 1, in the signal path SL1, the filter 20-1 is provided from the branch point J1 of the signal path SL5 to the speaker 10-1A. The filter 20-1 in the present embodiment is a high-pass filter that passes a signal having a frequency equal to or higher than a cutoff frequency and cuts off a signal having a frequency lower than the cutoff frequency. The cutoff frequency of the filter 20-1 is determined in correspondence with the lower limit frequency of the playback frequency band of the speaker 10-1A. More specifically, the cutoff frequency of the filter 20-1 is set in the vicinity of the lower limit frequency of the playback band of the speaker 10-1A. The filter 20-1 is provided for the purpose of avoiding damage to the speaker 10-1A due to a tone signal of a frequency lower than the above-described cutoff frequency being given to the speaker 10-1A. The filter 20-1 of the present embodiment is a high-pass filter, but may be a band-pass filter. The filter 20-1 is an example of the 1 st filter in the present invention.

The amplifier 310-2 amplifies the tone signal S2 to a level suitable for speaker driving. Amplifier 310-2 outputs amplified tone signal S2A to signal path SL2 to speaker 10-2A. Amplifier 310-2 is an example of the 2 nd amplifier in the present invention. Signal path SL2 from amplifier 310-2 to speaker 10-2A is an example of the 2 nd signal path in the present invention. The tone signal S2a is an example of the 2 nd tone signal in the present invention. The signal path SL6 branched from the signal path SL2 to the speaker 10-7 is an example of the 8 th signal path in the present invention. As shown in fig. 1, in the signal path SL2, the filter 20-2 is provided from the branch point J2 of the signal path SL6 to the speaker 10-2A. The filter 20-2 is also a high-pass filter, as is the filter 20-1. The cutoff frequency of the filter 20-2 is set in the vicinity of the lower limit frequency of the playback band of the speaker 10-2A. The filter 20-2 is provided to avoid damage to the speaker 10-2A, similarly to the filter 20-1. The filter 20-2 may be a band-pass filter, as with the filter 20-1. The filter 20-2 is an example of the 2 nd filter in the present invention.

The amplifier 310-3 amplifies the tone signal S3 to a level suitable for speaker driving. Amplifier 310-3 outputs amplified tone signal S3A to signal path SL3 to speaker 10-3A. Amplifier 310-3 is an example of the 3 rd amplifier in the present invention. Signal path SL3 from amplifier 310-3 to speaker 10-3A is an example of signal path 3 in the present invention. Tone signal S3a is an example of the 3 rd tone signal in the present invention. As shown in fig. 1, in the present embodiment, a signal path SL7 to the speaker 10-5 branches from the signal path SL 3. The signal path SL7 is an example of the 6 th signal path in the present invention. As shown in fig. 1, in the signal path SL3, a filter 20-3 is provided between the branching point J3 with the signal path SL7 and the speaker 10-3A. The filter 20-3 is also a high-pass filter, as is the filter 20-1. The cutoff frequency of the filter 20-3 is set in the vicinity of the lower limit frequency of the playback band of the speaker 10-3A. The filter 20-3 is provided to avoid damage to the speaker 10-3A, similarly to the filter 20-1. The filter 20-3 also plays a role of sound quality adjustment for flattening the frequency response of the portion where the playback frequency band of the speaker 10-3A and the playback frequency band of the speaker 10-5 overlap. The filter 20-3 may be a band-pass filter, similarly to the filter 20-1. The filter 20-3 is an example of the 3 rd filter in the present invention.

The amplifier 310-4 amplifies the tone signal S4 to a level suitable for speaker driving. Amplifier 310-4 outputs amplified tone signal S4A to signal path SL4 to speaker 10-4A. Amplifier 310-4 is an example of the 4 th amplifier in the present invention. The signal path SL4 is an example of the 4 th signal path in the present invention. The tone signal S4a is an example of the 4 th tone signal in the present invention. As shown in fig. 1, in the present embodiment, a signal path SL8 to the speaker 10-6 branches from the signal path SL 4. The signal path SL8 is an example of the 7 th signal path in the present invention. As shown in fig. 1, in the signal path SL4, the filter 20-4 is provided from the branch point J4 of the signal path SL8 to the speaker 10-4A. The filter 20-4 is also a high pass filter, as is the filter 20-1. The cutoff frequency of the filter 20-4 is set in the vicinity of the lower limit frequency of the playback band of the speaker 10-4A. The filter 20-4 is provided to avoid damage to the speaker 10-4A and adjustment of sound quality, similarly to the filter 20-3. The filter 20-4 may be a band-pass filter, similar to the filter 20-1. The filter 20-4 is an example of the 4 th filter in the present invention.

In the present embodiment, amplifier 310-1 drives speaker 10-1A and speaker 10-7. Amplifier 310-2 drives speaker 10-2A and speaker 10-7. Amplifier 310-3 drives speaker 10-3A and speaker 10-5. Amplifier 310-4 drives speaker 10-4A and speaker 10-6.

Fig. 2 is a plan view of a vehicle C mounted with the acoustic system 1A. In FIG. 2, the filters 20-1 to 20-4 and the driving device 30 are not shown. In the cabin CR of the vehicle C, 4 seats 51 to 54, a ceiling 6, a right front door 71, a left front door 72, a right rear door 73, and a left rear door 74 are arranged in a rectangular arrangement. When the vehicle C is a product for japan, the seat 51 is a driver seat and the seat 52 is a passenger seat. However, when the vehicle C is a product for the united states or europe, the seat 51 is a passenger seat and the seat 52 is a driver seat. It is assumed in the following description that the vehicle C is a product oriented in japan. The seat 53 is a rear right seat, and the seat 54 is a rear left seat. The seats 51 to 54 face in a common direction. Hereinafter, the seat 51 and the seat 52 may be referred to as a "front seat", and the seat 53 and the seat 54 may be referred to as a "rear seat".

As shown in fig. 2, the speaker 10-7 is disposed behind the rear seat in the present embodiment. More specifically, as shown in fig. 2, the speaker 10-7 is disposed at a position between the seat 53 and the seat 54 and behind the seat 53 and the seat 54. In the present embodiment, the speakers 10-1A, 10-2A, 10-3A, 10-4A, 10-5 and 10-6 are each a so-called door speaker. As shown in fig. 2, the speakers 10-3A and 10-5 are disposed on the right front door 71 in such a posture that their sound emitting surfaces face the seat 51. As shown in fig. 2, the speakers 10-4A and 10-6 are disposed on the left front door 72 in such a posture that their sound-emitting surfaces face the seat 52. As shown in fig. 2, the speaker 10-1A is disposed on the right rear door 73 in a posture in which the sound-emitting surface faces the seat 53. The speaker 10-2A is disposed at the left rear door 74 in a posture in which the sound-emitting surface is directed toward the seat 54.

Fig. 3 is a graph showing a frequency distribution of sound pressure of sound measured in the front seat of the vehicle C having the acoustic system 1A. The pattern subwwf in fig. 3 shows the frequency distribution of sound pressure with respect to the heavy bass-frequency tones emitted by the speaker 10-7. The graph WF in fig. 3 shows the frequency distribution of sound pressure with respect to low-frequency sounds emitted from the speakers 10-5 and 10-6. Graph TW of fig. 3 shows a frequency distribution of sound pressure with respect to high-frequency sounds emitted from speakers 10-3A and 10-4A. As shown in fig. 3, sounds in which sound pressures are distributed without gaps from heavy bass frequencies to high frequencies were measured in the front seat. Therefore, the passenger seated in the front seat can hear the sound in the frequency band from the heavy bass frequency to the high frequency.

Fig. 4 is a graph showing a frequency distribution of sound pressure of sound measured in the rear seat of the vehicle C having the acoustic system 1A. Graph SQ in fig. 4 shows the frequency distribution of sound pressure with respect to the sound of the middle frequency emitted from speaker 10-1A and speaker 10-2A. The pattern sub WF, the pattern WF, and the pattern TW are the same as those in fig. 3.

The reproduction band of the speaker 10-1A is expanded to a higher frequency side than the reproduction band of the speaker 10-5. Similarly, the reproduction band of the speaker 10-2A is also expanded to a higher frequency side than the reproduction band of the speaker 10-6. Therefore, if the speaker 10-5 and the speaker 10-6 are not provided and only the speaker 10-1A and the speaker 10-2A are provided, the sound pressure at low frequencies is insufficient, but the sound output from the speaker 10-5 and the speaker 10-6 supplements the sound pressure at low frequencies in the present embodiment. In fig. 4, the case where the sound pressure of the low frequency is supplemented by the sounds output from the speakers 10-5 and 10-6 is shown by a graph of a broken line. The reproduction band of the speaker 10-1A is expanded to a lower frequency side than the reproduction band of the speaker 10-3A. Similarly, the reproduction band of the speaker 10-2A is expanded to the low frequency side as compared with the reproduction band of the speaker 10-4A. Therefore, although the sound pressure of high frequency is insufficient in the case of only the speaker 10-1A and the speaker 10-2A without the speaker 10-3A and the speaker 10-4A, the sound output from the speaker 10-3A and the speaker 10-4A supplements the sound pressure of high frequency in the present embodiment. Fig. 4 shows a graph of a one-dot chain line in which the sound outputted from the speaker 10-3A and the speaker 10-4A complements the sound pressure of the high frequency. Therefore, according to the acoustic system 1A of the present embodiment, even a passenger sitting on the rear seat can hear sound in a frequency band from heavy bass to high frequency.

In addition, in the present embodiment, the speaker 10-1A and the speaker 10-2A driven as a set with the speaker 10-7 as a subwoofer are midrange speakers. As described above, the reproduction band of the speaker 10-1A is expanded to the low frequency side as compared with the reproduction band of the speaker 10-3A as a tweeter. Similarly, the reproduction band of the speaker 10-2A is expanded to the low frequency side as compared with the reproduction band of the speaker 10-4A as a high pitch speaker. Therefore, the amplitude of either or both of the sound signal S1 and the sound signal S2 is increased in the preamplifier in accordance with the driving of the speaker 10-7, and even if clipping occurs in either or both of the amplifier 310-1 and the amplifier 310-2, high-frequency noise resulting from clipping of the input signal is not output from the speaker 10-1A and the speaker 10-2A. Since the sound pressure distribution of the heavy bass is determined according to the shape of the vehicle interior CR, even if the amplitudes of the sound signals S1 and S2 are increased, the sound pressure of the heavy bass is not necessarily increased in the rear seats as compared with the front seats, and the balance of the sound pressures extending from the heavy bass to the high frequency in the rear seats does not collapse.

As described above, according to the present embodiment, it is possible to output a wide-band sound from a heavy bass sound to a high frequency sound without increasing the number of channels of the driving device 30 and without adding an amplifier for a heavy bass sound. In addition, according to the present embodiment, it is possible to drive the subwoofer while avoiding high-frequency noise output from the speaker driven as a set with the subwoofer.

2. Modification example

The above embodiments can be variously modified. The following examples show specific modifications. The 2 or more modes arbitrarily selected from the following examples can be appropriately combined as long as they are not contradictory to each other.

2-1. Modification example 1

Speakers 10-1A, 10-2A, 10-3A, 10-4A, 10-5, and 10-6 are not limited to car door speakers. For example, the speakers 10-3A and 10-4A may be disposed on the upper surface of the front instrument panel or the A-pillar portion. In addition, speakers 10-1A, 10-2A, 10-3A, 10-4A, 10-5 and 10-6 each do not have to be facing the seat. In the above embodiment, the speaker 10-1A, the speaker 10-2A, and the speaker 10-7 are disposed on the rear seat side, and the speaker 10-3A, the speaker 10-4A, the speaker 10-5, and the speaker 10-6 are disposed on the front seat side. However, speakers 10-3A to 10-6 may be disposed on the rear seat side, and speakers 10-1A, 10-2A, and 10-7 may be disposed on the front seat side. For example, when the speaker 10-1A, the speaker 10-2A, and the speaker 10-7 are disposed on the front seat side, the speaker 10-7 may be disposed under the front passenger seat or the driver seat. In the above embodiment, the acoustic system 1A according to one embodiment of the present invention is described, but a vehicle C mounted with the acoustic system 1A may be manufactured or sold.

2-2. Modification 2

The efficiency of speaker 10-7 may be greater than or equal to the efficiency of speaker 10-5. In addition, the efficiency of speaker 10-7 may also be greater than or equal to the efficiency of speaker 10-6. In the case where the efficiency of speaker 10-7 is greater than or equal to the efficiency of speaker 10-5, the gain of amplifier 310-1 may be less than or equal to the gain of amplifier 310-3. Likewise, in the case where the efficiency of speaker 10-7 is greater than or equal to the efficiency of speaker 10-6, the gain of amplifier 310-2 may be less than or equal to the gain of amplifier 310-4.

2-3. Modification 3

In the above embodiment, the speaker 10-7 is a dual voice coil speaker, but a subwoofer having 1 voice coil may be used as the speaker 10-7. In the case of using a subwoofer with 1 voice coil as the speaker 10-7, a monaural sound signal generated from either the sound signal S1a or the sound signal S2a or the sound signal S1a or the sound signal S2a may be given to the speaker 10-7.

2-4. Modification example 4

In the above embodiment, the speakers 10-5 and 10-6 may be omitted from the acoustic system 1A shown in fig. 1. This is because even if the speaker 10-5 and the speaker 10-6 are omitted, the sound pressure of low frequencies heard by the passenger on the front seat can be obtained by the sound output from the speaker 10-1A and the speaker 10-2A. In the embodiment where the speaker 10-5 and the speaker 10-6 are omitted, it is preferable to increase the upper limit frequency of the reproduction band of the speaker 10-7 as compared with the above-described embodiment. This is because the sound output from the speaker 10-7 complements the sound of low frequencies heard by the passenger in the front seat. In addition, the filters 20-1 to 20-4 in the above embodiment are not essential, and the filters 20-1 to 20-4 may be omitted. The speaker 10-1A, the speaker 10-2A, the speaker 10-3A, the speaker 10-4A, the speaker 10-5, the speaker 10-6, and the speaker 10-7 are not essential components of the in-vehicle audio system of the present invention, and the in-vehicle audio system of the present invention may include the driving device 30 for driving each of the speaker 10-1A, the speaker 10-2A, the speaker 10-3A, the speaker 10-4A, the speaker 10-5, the speaker 10-6, and the speaker 10-7.

2-5. Modification example 5

In the above embodiment, the speakers 10-3A and 10-5 are arranged on the right side of the front seat, and the speakers 10-4A and 10-6 are arranged on the left side of the front seat. However, instead of a combination of a tweeter and a woofer, a full range speaker may be used. In the acoustic system 1B shown in fig. 5, a full-range speaker, i.e., speaker 10-3B, is provided in place of speakers 10-3A and 10-5, and a full-range speaker, i.e., speaker 10-4B, is provided in place of speakers 10-4A and 10-6. Speaker 10-3B is an example of the 1 st full range speaker in the present invention. Speaker 10-4B is an example of a 2 nd full range speaker in the present invention. In addition, in the acoustic system 1B, there is no need to consider damage avoidance and sound quality adjustment of the speakers 10-3B and 10-4B, and therefore the filters 20-3 and 20-4 are omitted. According to this embodiment, it is possible to output a wide-band sound ranging from a heavy bass sound to a high frequency sound without increasing the number of channels of the driving device 30 and without adding an amplifier for a heavy bass sound. Further, according to this aspect, it is possible to drive the subwoofer while avoiding high-frequency noise output from the speaker driven as a set with the subwoofer.

2-6. Modification example 6

In the above embodiment, the speakers 10-1A and 10-2A are midrange speakers. However, instead of the midrange speaker, the full range speaker and the speaker 10-7 may be driven as a set. In acoustic system 1C shown in fig. 6, full-range speaker 10-1B is provided in place of speaker 10-1A, and full-range speaker 10-2B is provided in place of speaker 10-2A. In the acoustic system 1C shown in fig. 6, by setting the cutoff frequencies of the filter 20-1 and the filter 20-2, it is possible to drive the speaker 10-7 while avoiding high-frequency noise output from the speakers 10-1B and 10-2B.

3. Modes grasped from at least 1 of embodiment and modifications

An audio system 1A, which is an example of an in-vehicle audio system according to the present invention, includes an amplifier 310-1, which is an example of a 1 st amplifier, an amplifier 310-2, which is an example of a 2 nd amplifier, an amplifier 310-3, which is an example of a 3 rd amplifier, and an amplifier 310-4, which is an example of a 4 th amplifier. The 1 st amplifier outputs a sound signal S1A, which is an example of a 1 st sound signal, to the speaker 10-1A, which is an example of a 1 st midrange speaker, via the signal path SL1, which is an example of a 1 st signal path. The 2 nd amplifier outputs sound signal S2A, which is an example of a 2 nd sound signal, to speaker 10-2A, which is an example of a 2 nd midrange speaker, via signal path SL2, which is an example of a 2 nd signal path. The 3 rd amplifier outputs a sound signal S3A, which is an example of the 3 rd sound signal, to the speaker 10-3A, which is an example of the 1 st tweeter, and the speaker 10-5, which is an example of the 1 st woofer. The 4 th amplifier outputs sound signal S4A, which is an example of the 4 th sound signal, to speaker 10-4A, which is an example of the 2 nd tweeter, and speaker 10-6, which is an example of the 2 nd woofer. The 3 rd sound signal is input to the 1 st tweeter through a signal path SL3, which is an example of a 3 rd signal path from the 3 rd amplifier to the 1 st tweeter. The 4 th sound signal is input to the 2 nd high-frequency speaker via a signal path SL4 which is an example of a 4 th signal path from the 4 th amplifier to the 2 nd high-frequency speaker. The 1 st sound signal is input to the speaker 10-7, which is an example of a subwoofer, via the signal path SL5, which is an example of the 5 th signal path branched from the 1 st signal path. The 1 st woofer is supplied with the 3 rd sound signal via a signal path SL7, which is an example of a 6 th signal path branched from the 3 rd signal path. The 4 th sound signal is input to the 2 nd woofer through a signal path SL8, which is an example of a 7 th signal path branched from the 4 th signal path. The 1 st midrange speaker, the 1 st tweeter, and the 1 st woofer are provided on the same side of the right and left of a vehicle C, which is an example of a vehicle according to the present invention. The 2 nd midrange speaker, the 2 nd high-frequency speaker, and the 2 nd low-frequency speaker are provided on an opposite side of the left and right of the vehicle from the 1 st midrange speaker. According to this aspect, since the subwoofer and the 1 st midrange speaker are driven as a set, it is possible to output sounds in a frequency band from the subwoofer to the high frequency without increasing the number of channels of the in-vehicle audio system having the standard 4-channel amplifier and without adding an amplifier for subwoofer.

In a more preferable aspect of the in-vehicle audio system, a reproduction band of the 1 st midrange speaker is expanded to a lower frequency side than a reproduction band of the 1 st tweeter. According to this aspect, by increasing the amplitude of the 1 st sound signal to be larger than the amplitude of the 3 rd sound signal in order to drive the subwoofer, it is possible to avoid high-frequency noise caused by clipping from being output from the 1 st midrange speaker even if clipping occurs in the 1 st amplifier.

In a more preferred embodiment, the in-vehicle audio system may be configured such that a cutoff frequency is determined in accordance with a lower limit frequency of a playback frequency band of the 1 st intermediate frequency speaker, and a filter 20-1, which is an example of a 1 st filter that cuts off a signal having a frequency lower than the cutoff frequency, is provided in a signal path from a branch point between the 1 st signal path and the 5 th signal path to the 1 st intermediate frequency speaker among the 1 st signal paths. In the car audio system according to the present embodiment, the 1 st filter is provided in a signal path from a branch point J1, which is an example of a branch point between the 1 st signal path and the 5 th signal path, to the 1 st midrange speaker, among the 1 st signal paths. According to this aspect, it is possible to avoid damage to the 1 st midrange speaker caused by a signal having a frequency lower than the cutoff frequency being input to the 1 st midrange speaker.

In a more preferred embodiment of the in-vehicle audio system, the 2 nd sound signal may be further input to the subwoofer through a signal path SL6, which is an example of an 8 th signal path branched from the 2 nd signal path. In the in-vehicle audio system according to the present aspect, the subwoofer speaker includes a 1 st voice coil connected to the 5 th signal path and a 2 nd voice coil connected to the 8 th signal path. According to this embodiment, a circuit for generating a monaural sound signal from the 1 st sound signal and the 2 nd sound signal can be omitted. In addition, according to this aspect, since the subwoofer is driven by the 1 st sound signal and the 2 nd sound signal, the sound pressure can be increased as compared with the aspect in which the subwoofer is driven only by the 1 st sound signal.

In a more preferable embodiment of the in-vehicle audio system, a reproduction band of the 1 st woofer is expanded to a low frequency side compared with the 1 st midrange speaker, and a reproduction band of the 2 nd woofer is expanded to a low frequency side compared with the 2 nd midrange speaker. According to this aspect, the sound on the low frequency side of the reproduction frequency band of the 1 st and 2 nd midrange speakers is supplemented by the 1 st and 2 nd woofers, and the sound having impact force can be output.

In a more preferred aspect of the in-vehicle audio system, the 1 st high-frequency speaker and the 1 st low-frequency speaker and the 2 nd high-frequency speaker and the 2 nd low-frequency speaker may be disposed in front of the vehicle interior, and the 1 st midrange speaker, the 2 nd midrange speaker and the subwoofer may be disposed behind the vehicle interior.

An audio system 1B, which is an example of a car audio system according to the present invention, includes an amplifier 310-1, which is an example of a 1 st amplifier, an amplifier 310-2, which is an example of a 2 nd amplifier, an amplifier 310-3, which is an example of a 3 rd amplifier, and an amplifier 310-4, which is an example of a 4 th amplifier. The 1 st amplifier outputs a sound signal S1A, which is an example of a 1 st sound signal, to the speaker 10-1A, which is an example of a 1 st midrange speaker, via the signal path SL1, which is an example of a 1 st signal path. The 2 nd amplifier outputs sound signal S2A, which is an example of a 2 nd sound signal, to speaker 10-2A, which is an example of a 2 nd midrange speaker, via signal path SL2, which is an example of a 2 nd signal path. The 3 rd amplifier outputs sound signal S3a, which is an example of the 3 rd sound signal, to speaker 10-3B, which is an example of the 1 st full range speaker, via signal path SL3, which is an example of the 3 rd signal path. The 4 th amplifier outputs sound signal S4a, which is an example of a 4 th sound signal, to speaker 10-4B, which is an example of a 2 nd full range speaker, via signal path SL4, which is an example of a 4 th signal path. The 1 st sound signal is input to the speaker 10-7, which is an example of a subwoofer, via the signal path SL5, which is an example of the 5 th signal path branched from the 1 st signal path. The 1 st midrange speaker and the 1 st full-range speaker are provided on the same side of the vehicle C, which is an example of the vehicle according to the present invention. The 2 nd midrange speaker and the 2 nd full-range speaker are provided on an opposite side of the left and right sides of the vehicle from the 1 st midrange speaker. In this aspect, since the subwoofer and the 1 st midrange speaker are driven as a set, it is possible to output sounds in a frequency band from the subwoofer to the high frequencies without increasing the number of channels of the car audio system having the standard 4-channel amplifier and without adding the subwoofer.

A vehicle C, which is an example of the vehicle according to the present invention, has the in-vehicle audio system of any of the above-described aspects. According to this aspect, it is possible to output a wide-band sound from a heavy bass sound to a high frequency sound without increasing the number of channels of the in-vehicle audio system having a standard 4-channel amplifier and without adding an amplifier for heavy bass sounds.

Description of the reference numerals

1A, 1B, 1C … sound system, 10-1A, 10-1B, 10-2A, 10-2B, 10-3A, 10-3B, 10-4A, 10-4B, 10-5, 10-6, 10-7 … speakers, 20-1, 20-2, 20-3, 20-4 … filters, 30 … driver, 310-1, 310-2, 310-3, 310-4 … amplifier, SL1, SL2, SL3, SL4, SL5, SL6, SL7, SL8 … signal path, S1, S2, S3, S4, S1A, S2A, S3A, S4A … tone signal.