JPH04330832A - Acoustic device for vehicle - Google Patents

Abstract

PURPOSE:To prevent the generation of a howling at the time of a handfree communication, and also to prepare a suitable sound field at the time of using an audio. CONSTITUTION:At the time of using a microphone 9 for telephone provided at the driver's seat, a frequency band changing means 18 which adjusts the output frequency band of a speaker system 5 at the back part of a vehicle chamber to the frequency band of a voice, is provided. Thus, the handfree communication in which the generation of the howling of a transmitted voice inputted to the microphone 9 with a received voice from the speaker system 5 is prevented, can be realized. And also, at the time of enjoying a stereo playing, the frequency band of the speaker system 5 is turned through the frequency band changing means 18 back to the original frequency band for the stereo.

Description

[Detailed description of the invention]

0001

[Industrial Application Field] The present invention relates to a vehicle audio device.
Specifically, it is a speaker system that combines a hands-free telephone microphone installed in the driver's seat of a vehicle such as a car, and a high-frequency band speaker and a low-frequency band speaker placed in the rear of the vehicle interior. The present invention relates to a vehicle audio device equipped with a vehicle audio system.

0002

2. Description of the Related Art Vehicles such as automobiles are now equipped with so-called car telephones that allow telephone calls to be made between the inside and outside of the vehicle while the vehicle is running. In order to facilitate calls especially while driving, such car phones use a conventional handset with an integrated microphone and handset, as described in Japanese Utility Model Application Publication No. 61-195661. In addition to voice calls, some models allow so-called hands-free phone calls by operating a selector switch, using a microphone installed in the driver's seat for transmitting and an audio speaker system installed in the passenger compartment for receiving. In such cases, if the transmitting microphone and the receiving speaker system are placed close to each other, howling may occur, so it is recommended to use the speaker system located at the rear of the passenger compartment for receiving. many.

0003

[Problem to be Solved by the Invention] As speaker systems become more sophisticated, a two-way speaker system that combines a high-frequency band speaker and a low-frequency band speaker is sometimes installed on the left and right sides of the rear of the vehicle. . However, this speaker system cannot output the so-called midrange sound frequency band, and cannot be used for hands-free reception. The present invention has been made in consideration of these circumstances, and provides a vehicle that prevents howling from occurring when using a hands-free telephone microphone and also forms a suitable sound field when using audio. Our goal is to provide an acoustic device for

0004

[Means for Solving the Problems] The present invention combines a hands-free type telephone microphone provided in the driver's seat, a high frequency band speaker and a low frequency band speaker provided in the rear of the vehicle interior. In order to achieve the above-mentioned object in a vehicle acoustic device equipped with a 2-way speaker system, when the above-mentioned telephone microphone is used, the frequency band is changed to adjust the output frequency band of the above-mentioned speaker system to the audio frequency band. We have measures in place.

[0005]

[Operation] In the so-called network method, when the speaker system installed at the rear of the vehicle is used for receiving calls, the LC network installed in the speaker system is used to output the output of the high frequency band speaker and the low frequency band speaker. Both frequency bands may be changed to audio frequency bands. In other words, the LC network attached to the speaker system can be used as a frequency band changing means to change and adjust the frequency band allocated to each speaker. In hands-free calls using such a speaker system, howling does not occur because the speaker system is located far from the driver's seat microphone. Note that this adjustment of the LC network may be performed using a control signal from a control section within the telephone unit. In addition, in the multi-channel system, the equalizer amplifier lowers the output frequency band input to each speaker to include the audio frequency band, that is, lowers the frequency band to the high frequency band speakers to the lower limit of the audio frequency band. , it is only necessary to adjust the frequency band to the low frequency band speaker to raise it to the upper limit of the audio frequency band. The equalizer amplifier may be adjusted using a control signal from a control section within the telephone unit.

[0006]

[Effects of the Invention] The vehicle audio system of the present invention is capable of outputting sound from a two-way speaker system located at the rear of the vehicle cabin when using a telephone microphone installed in the driver's seat. Since a frequency band changing means is provided to adjust the output frequency band of the speaker system to the audio frequency band, the transmitted sound input to the telephone microphone,
This eliminates howling from the voice received from the speaker system at the rear of the vehicle. Further, since the speaker system can easily return to the original stereo frequency band using the frequency band changing means, it is possible to easily create a suitable sound field when using audio.

[0007]

EXAMPLES The present invention will be explained in detail below based on examples thereof. The vehicle audio device shown in this example is capable of preventing howling when using a hands-free telephone microphone, and is also capable of creating a suitable sound field when using audio. It is configured as follows. As shown in FIG. 2, a passenger compartment 2 of a car 1
is equipped with a hands-free telephone set 4 that is used in combination with an audio device 3. This telephone set 4 has a hand-held handset 7 placed immediately behind the shaft lever 6, and a microphone 9 placed on the instrument panel 8 for voice transmission.
A two-way audio speaker system 5 placed on a rear package tray 11 behind the 0 can also be used for receiving calls. In other words, in this combination system, as shown in FIG. 1, the output signal sent from the audio unit 12 is amplified by the power amplifier 14, and the frequency band is distributed to the two speakers 16 and 17 using the network method. While audio sound is emitted from the speaker system 5 of the telephone unit 13, by switching the changeover switch 15 provided on the telephone unit 13, a call using the handset 7 and a hands-free call using the microphone 9 and its speaker system 5 can be made. Allowing you to choose. To be more specific, the audio unit 12 is called a preamplifier, and although not shown, it includes a head amplifier that increases the input signal from the cartridge, and an equalizer amplifier that returns the sound of processed records to its original normal state and amplifies it. It also has a built-in tone control amplifier and filter to adjust the sound quality. The two-way speaker system 5 driven by this audio unit 12 includes a tweeter 16 which is a high frequency band speaker and a woofer 17 which is a low frequency band speaker, and each speaker 16 and 17 is connected to each other by an LC network 18. It uses a network system that allocates the frequency bands it is responsible for. And this LC
As will be described later, the network 18 is used as a frequency band changing means for adjusting the frequency bands of both speakers 16 and 17 to extend to the audio frequency band based on instructions from the telephone unit 12. A full-range speaker 20 is placed on the front door 24 corresponding to the driver's seat 23 (see Fig. 2) of the vehicle interior 2, and together with the two-way speaker system 5 installed at the rear, a full-scale stereo speaker system is installed. It consists of On the other hand, although not shown, the telephone unit 13 includes a transmitting/receiving section that transmits and receives a calling signal and voice to and from the other party, an oscillating section that sends a calling signal to the transmitting/receiving section, and a control section that controls these. An antenna 21, a microphone 9, and a transmitter/receiver 7 are connected to this. A changeover switch 15 is connected to the control section, so that it is possible to arbitrarily select between a normal call using the handset 7 and a hands-free call using the microphone 9 and speaker system 5 at any time. When making a hands-free call, a control signal from the control section of the telephone unit 13 is sent to the LC network 18 which functions as a frequency band changing means, and the output frequency bands of the tweeter 16 and woofer 17 are changed to the respective audio frequencies. Bandwidth (Figure 3
(refer to the broken line) to a midrange frequency of around 1KHz. Thereby, the voice of the other party can be heard from both the left and right speakers 16 and 17 arranged at the rear of the vehicle compartment 2. Since this speaker system 5 is provided in a position apart from the microphone 9 arranged on the instrument panel 8, the sound received from the other party by this speaker system 5 is mixed with the transmitted sound input to the microphone 9 and howling. Things like that will be avoided. After the call ends, by operating the changeover switch 15, both speakers 16 and 17 are immediately converted to the original audio frequency band via the LC network 18, thereby easily forming a good sound field. You can enjoy stereo music. In other words, it is possible to selectively achieve both hands-free phone calls without feedback and stereo performance with good sound quality.

FIG. 4 shows a different embodiment in which each power amplifier 3 is connected to an equalizer amplifier 32 arranged outside the audio unit 31 using a multi-channel amplifier system.
The frequency characteristics of the output signals sent to the telephone units 3 and 34 are adjusted to extend to the voice frequency band by operating a changeover switch 15 provided on the telephone unit 13. That is, in this case, the equalizer amplifier 32 is used as a frequency band changing means, and the frequency band of the output signal to the tweeter 16 is changed to 500, which is the lower limit of the audio frequency band, by the control signal from the telephone unit 13.
Hz and raise the frequency band of the output signal to the woofer 17 to 2 KHz, which is the upper limit of the audio frequency band (see the broken line in FIG. 5).

As described above in the embodiments, according to the present invention, when using the telephone microphone provided in the driver's seat, the frequency band of the speaker system at the rear of the vehicle compartment is adjusted to the audio frequency band. Since the frequency band changing means is provided, it is possible to selectively achieve both hands-free communication without feedback and stereo performance with good sound quality.

[Brief explanation of drawings]

FIG. 1 is a block diagram showing the configuration of an embodiment of a vehicle acoustic device of the present invention.

[Fig. 2] A perspective view of the vehicle compartment.

FIG. 3 is a graph for explaining adjustment of the frequency band of the speaker system by the LC network.

FIG. 4 is a block diagram showing configuration correspondence in different embodiments.

FIG. 5 is a graph for explaining adjustment of the frequency band of a speaker system by an equalizer amplifier.

[Explanation of symbols]

5... Speaker system, 9... Telephone microphone, 16... High frequency band speaker (tweeter), 17... Low frequency band speaker (woofer), 18... Frequency band changing means (
LC network), 32...frequency band changing means (equalizer amplifier).

Claims (1)

[Claims] [Claim 1] A two-way speaker system that combines a hands-free telephone microphone installed in the driver's seat and a high-frequency band speaker and a low-frequency band speaker placed in the rear of the vehicle interior. 1. A vehicle acoustic device comprising: a frequency band changing means for adjusting an output frequency band of the speaker system to a voice frequency band when the telephone microphone is used.