WO2013179332A1

WO2013179332A1 - Audio device

Info

Publication number: WO2013179332A1
Application number: PCT/JP2012/003466
Authority: WO
Inventors: 村上　洋介
Original assignee: 三菱電機株式会社
Priority date: 2012-05-28
Filing date: 2012-05-28
Publication date: 2013-12-05
Also published as: JPWO2013179332A1; WO2013179332A9

Abstract

This audio device is equipped with: a storage unit (11) for storing frequency characteristics and phase characteristics of an audio signal that correspond to an arrangement of speakers; a current detection circuit (16) for detecting speakers that are connected to output terminals (17); a DSP (13) that applies signal processing to the audio signal so as to attain preset frequency characteristics and phase characteristics and outputs the resulting audio signal to a power amplifier (15); and a CPU (10) that identifies a speaker arrangement on the basis of a detection result of the current detection circuit (16), reads frequency characteristics and phase characteristics of the audio signal that correspond to the identified arrangement from the storage unit (11), sets the characteristics on the DSP (13), and controls the power amplifier (15) according to said arrangement.

Description

Audio equipment

The present invention relates to an audio device that automatically sets the frequency and phase characteristics of output sound according to the arrangement of speakers.

The sound field correction apparatus described in Patent Document 1 stores in advance sound field adjustment data corresponding to a speaker position and a listening position for each attribute information indicating a vehicle manufacturer, a vehicle type, and a grade, and a user sets a setting screen. If the attribute information is set based on the sound field adjustment, the sound field adjustment data corresponding to the attribute information is read, and the sound output of each speaker is corrected using the sound field adjustment data.

JP 2003-153400 A

The conventional technique represented by Patent Document 1 has a problem that the user needs to set attribute information each time the arrangement of the speakers is changed. In this case, if the user does not recognize the attribute information corresponding to the current vehicle, the user may continue to listen with inappropriate acoustic characteristics due to an incorrect setting.

The present invention has been made to solve the above-described problems, and allows the user to set the frequency characteristics and phase characteristics of the output sound according to the arrangement of the speakers without performing a specific operation. An object is to obtain an audio device.

The audio apparatus according to the present invention includes an output terminal connected to a speaker arranged at a predetermined position for outputting an amplified audio signal to an amplifier, and the frequency characteristics of the audio signal corresponding to the arrangement of the speaker and A storage unit that stores phase characteristics; a detection unit that detects a speaker connected to the output terminal; and a signal processing unit that performs signal processing of the audio signal so that the set frequency characteristic and phase characteristic are obtained and outputs the result to the amplifier. The speaker arrangement is determined based on the detection result of the detection unit, and the frequency characteristic and phase characteristic of the audio signal corresponding to the determined arrangement are read from the storage unit and set in the signal processing unit. And a control unit for controlling.

According to the present invention, there is an effect that it is possible to set the frequency characteristic and phase characteristic of the output sound in accordance with the arrangement of the speakers without performing a specific operation by the user.

It is a block diagram which shows the structure of the audio apparatus which concerns on Embodiment 1 of this invention. 3 is a flowchart showing an operation performed by the audio apparatus according to Embodiment 1. It is a figure which shows the example of arrangement | positioning of a speaker. It is a figure which shows the frequency characteristic of the output sound of the speaker of each channel in 4-channel speaker arrangement | positioning. It is a block diagram which shows the structure of the audio apparatus based on Embodiment 2 of this invention. 10 is a flowchart illustrating an operation performed by the audio apparatus according to the second embodiment.

Hereinafter, in order to describe the present invention in more detail, modes for carrying out the present invention will be described with reference to the accompanying drawings.
Embodiment 1 FIG.
FIG. 1 is a block diagram showing a configuration of an audio apparatus according to Embodiment 1 of the present invention. An audio device 1 shown in FIG. 1 is an audio device mounted on a moving body (for example, a vehicle), and includes a CPU 10, a storage device 11, a sound reproduction device 12, a DSP 13, an oscillator 14, a power amplifier 15, a current detection circuit 16, An output terminal 17, a user interface unit 18, a display unit 19, and an operation unit 20 are provided.

The CPU 10 is a control unit that controls the operation of each component in the audio apparatus 1. Further, the CPU 10 reads out the frequency characteristic and phase characteristic of the audio signal corresponding to the speaker arrangement determined based on the detection result of the current detection circuit 16 from the storage device 11 and sets the audio signal in the DSP 13, and the power according to the arrangement configuration. The amplifier 15 is controlled.

The storage device 11 is a storage unit that stores the frequency characteristic and phase characteristic of the audio signal corresponding to the arrangement of the speakers, and the frequency characteristic and phase characteristic of the audio signal output via the external amplifier.
The sound reproduction device 12 is a device for reproducing an audio signal from a signal input from a sound source such as a CD or a DVD.

A DSP (Digital Signal Processor) 13 performs signal processing on the audio signal input from the audio reproduction device 12 so that the frequency characteristic and the phase characteristic set by the CPU 10 are obtained, and outputs the processed signal to the power amplifier 15.
The oscillator 14 is an oscillator that generates a test tone signal provided in the DSP 13, and outputs the test tone signal to the output terminal 17 via the power amplifier 15.

The power amplifier 15 is an amplifier that amplifies an audio signal output to an output terminal corresponding to each channel.
The current detection circuit 16 is a current detection unit that detects a current at the output terminal 17 from which the test tone signal is output.
The output terminal 17 is an output terminal connected to a speaker disposed at a predetermined position in a moving body such as a vehicle. The audio signal amplified by the power amplifier 15 is output from the speaker via the output terminal 17.

The user interface unit 18 includes a display unit 19 that displays various processing results of the audio device 1 and an operation unit 20 for performing various operation inputs to the audio device 1.
The display unit 19 is realized by a liquid crystal display or the like, and may include a touch panel corresponding to the operation unit 20. The operation unit 20 includes software keys that can be operated with a touch panel, in addition to operation input means such as hardware keys.

Next, the operation will be described.
FIG. 2 is a flowchart showing the operation of the audio apparatus according to Embodiment 1, and shows details of the automatic setting processing of the frequency and phase characteristics of the audio signal according to the arrangement of the speakers. In the following, as shown in FIG. 3, the audio device 1 is mounted on a vehicle, the front seat side two-channel speaker arrangement shown in FIG. 3 (a), and the front seat side shown in FIG. 3 (b). A case where the rear seat side has four-channel speakers and an external amplifier is connected to the output terminal 17 will be described as an example.

First, when the power supply of the audio apparatus 1 is activated, the CPU 10 transmits a command to output a test tone signal to the oscillator 14.
The oscillator 14 outputs a test tone signal to the output terminal 17 via the power amplifier 15 and the current detection circuit 16 in accordance with the command received from the CPU 10 (step ST1).

The current detection circuit 16 detects the current flowing through the speaker line including the output terminal 17 that has output the test tone signal. The detection result by the current detection circuit 16 is output to the CPU 10.
When a speaker is connected to the output terminal 17 from which the test tone signal is output (corresponding to a case where a predetermined load is connected), a predetermined value of current flows through the speaker line including the output terminal 17. Yes.
The CPU 10 determines whether or not a speaker is connected to the output terminal 17 based on whether or not the current value corresponding to the test tone signal is detected by the current detection circuit 16, and the audio device 1 is determined from the number of speakers as a result of this determination. The arrangement of the speakers connected to is determined (step ST2). Here, the speakers are arranged in two channels of left and right FL / FR on the front seat side shown in FIG. 3A, and left and right FL / FR on the front seat side and rear seat side shown in FIG. Either the left / right RL / RR four-channel speaker arrangement or an external amplifier is connected.
Therefore, when the CPU 10 determines that the number of speakers connected to the output terminal 17 is two based on the detection result by the current detection circuit 16, the CPU 10 determines that the left and right two-channel speaker arrangement is on the front seat side, When it is determined that the number of speakers connected to the output terminal 17 is four, it is determined that the left and right speakers on the front seat side and the left and right speakers on the rear seat side are arranged in four channels.
If it is determined that no speaker is connected to all output terminals 17 (all channels open), it is determined that an external amplifier is connected to the output terminal 17.

When it is determined that the left and right two-channel speaker arrangement is on the front seat side (step ST2; 2ch), the CPU 10 stores the frequency characteristic and phase characteristic of the audio signal corresponding to the left and right two-channel speaker arrangement on the front seat side. Read from the device 11 and set in the DSP 13. The DSP 13 processes the audio signal so that the frequency characteristic and phase characteristic set by the CPU 10 are obtained, and outputs the signal to the power amplifier 15.
At this time, the DSP 13 performs signal processing according to the setting from the CPU 10 so that the frequencies of the audio signals of both channels on the front seat side have flat characteristics.
Further, the CPU 10 performs control to turn off the amplifier of the channel on the rear seat side to which the speaker in the power amplifier 15 is not connected, according to the speaker arrangement of the left and right two channels on the front seat side. The processing so far corresponds to step ST3-1.

When it is determined that the left and right four-channel speakers are arranged on the front seat side and the rear seat side (step ST2; 4ch), the CPU 10 determines the left and right four-channel speakers on the front seat side and the rear seat side. The frequency characteristic and phase characteristic of the audio signal corresponding to the arrangement are read from the storage device 11 and set in the DSP 13. The DSP 13 processes the audio signal so that the frequency characteristic and phase characteristic set by the CPU 10 are obtained, and outputs the signal to the power amplifier 15.
At this time, according to the setting from the CPU 10, the DSP 13 has a frequency characteristic and a phase characteristic obtained by cutting a low-frequency component by a high-pass filter (HPF) in the audio signal output from the front seat side speaker as shown in FIG. The signal processing is performed as described above, and the audio signal output from the speaker on the rear seat side is subjected to signal processing so as to have a frequency characteristic and a phase characteristic with a high-frequency component cut by a low-pass filter (LPF).
The CPU 10 performs control to maintain the gain of the amplifier of the channel to which the speaker in the power amplifier 15 is connected according to the arrangement of the four-channel speakers. The processing so far corresponds to step ST3-2.

When it is determined that the external amplifier is connected (step ST2; all ch open), the CPU 10 reads out the frequency characteristic and phase characteristic of the audio signal output via the external amplifier from the storage device 11 and sets them in the DSP 13. To do.
The DSP 13 processes the audio signal so as to have the frequency characteristic and phase characteristic set by the CPU 10 and outputs the audio signal to the power amplifier 15.
At this time, the DSP 13 performs signal processing according to the setting from the CPU 10 so that the frequencies of the audio signals of all the channels have flat characteristics.
Further, since the input of another amplifier (external amplifier) is connected to the output terminal 17, the CPU 10 does not clip the input to the external amplifier. Is lower than the current value.

By performing the above-described series of processes every time the power is turned on, even when the audio apparatus 1 is attached to another vehicle and the arrangement of the speakers is changed, the storage apparatus 11 stores the speakers in the new vehicle interior. By storing the frequency characteristic and phase characteristic of the audio signal corresponding to the arrangement, the frequency characteristic and phase characteristic of the audio signal corresponding to the arrangement of the speaker are automatically set.

As described above, according to the first embodiment, the storage device 11 that stores the frequency characteristic and phase characteristic of the audio signal corresponding to the speaker arrangement, and the current detection circuit that detects the speaker connected to the output terminal 17. 16, the DSP 13 that performs signal processing of the audio signal so as to have the set frequency characteristics and phase characteristics and outputs the signal to the power amplifier 15, and the speaker arrangement are determined based on the detection result of the current detection circuit 16. A frequency characteristic and a phase characteristic of the audio signal corresponding to the arrangement are read from the storage device 11 and set in the DSP 13, and the CPU 10 controls the power amplifier 15 according to the arrangement.
In particular, an oscillator 14 that generates a test tone signal and outputs it to the output terminal 17 is provided. The current detection circuit 16 detects a current at the output terminal 17 that outputs the test tone signal, and the CPU 10 performs a test using the current detection circuit 16. Whether or not a speaker is connected to the output terminal 17 is determined based on whether or not a current value corresponding to the tone signal is detected, and the speaker arrangement is determined from the determination result.
With this configuration, it is possible to automatically set the frequency and phase characteristics of the output sound according to the arrangement of the speakers, without the user performing a specific operation.

Further, according to the first embodiment, the storage device 11 stores the frequency characteristics and phase characteristics of the audio signal output via the external amplifier, and the CPU 10 is based on the detection result by the current detection circuit 16. If it is determined that no speaker is connected to all the output terminals 17, it is determined that an external amplifier is connected to the output terminal 17, and the frequency characteristic and phase characteristic of the audio signal corresponding to the external amplifier are determined from the storage device 11. The data is read and set in the DSP 13, and the power amplifier 15 is controlled according to the connection of the external amplifier.
By doing so, it is possible to set the frequency characteristics and phase characteristics of the audio signal corresponding to the external amplifier even when the external amplifier is connected.

In the first embodiment, an example is given of a case where a 2-channel speaker arrangement on the front seat side, a 4-channel speaker arrangement on the front seat side and the rear seat side, and an external amplifier is connected to the output terminal 17. However, the present invention can be applied to speaker arrangements other than these.
That is, since a current of a predetermined value corresponding to the type (resistance value) of the speaker (load) flows through the speaker line including the output terminal 17 from which the test tone signal is output, the speaker is based on the detection result of the current value. Can be accurately determined. Therefore, if the frequency characteristics and phase characteristics of audio signals corresponding to various speaker arrangements are stored in the storage device 11, settings corresponding to the determined speaker arrangements can be automatically performed.

Embodiment 2. FIG.
FIG. 5 is a block diagram showing a configuration of an audio apparatus according to Embodiment 2 of the present invention, and shows an audio apparatus mounted on a moving body (for example, a vehicle) as in FIG.
An audio device 1A shown in FIG. 5 includes a CPU 10, a storage device 11, a sound reproduction device 12, a DSP 13, an oscillator 14, a power amplifier 15A, a current detection circuit 16, an output terminal 17, a user interface unit 18, a display unit 19, and an operation unit 20. It is configured with. In FIG. 5, the same components as those in FIG.

The power amplifier 15 </ b> A is an amplifier that amplifies an audio signal output to an output terminal corresponding to each channel, and includes a speaker diagnosis system 21.
The speaker diagnosis system 21 is a self-diagnosis system that generates a test tone signal and outputs the test tone signal to the output terminal 17 and detects a current at the output terminal 17 that has output the test tone signal.

Next, the operation will be described.
FIG. 6 is a flowchart showing the operation of the audio apparatus according to the second embodiment, and shows details of the automatic setting processing of the frequency and phase characteristics of the audio signal according to the arrangement of the speakers. As in the first embodiment, the audio device 1A is mounted on a vehicle, and the two-channel speaker arrangement on the front seat side shown in FIG. 3 (a), the front seat side shown in FIG. 3 (b), and A description will be given by taking, as an example, the arrangement of four-channel speakers on the rear seat side and the case where an external amplifier is connected to the output terminal 17.

First, when the power source of the audio apparatus 1A is activated, the CPU 10 transmits an instruction to perform speaker diagnosis to the power amplifier 15A.
The speaker diagnosis system 21 of the power amplifier 15A outputs a test tone signal to the output terminal 17 in accordance with the command received from the CPU 10 (step ST1a).

The speaker diagnosis system 21 detects the current flowing through the speaker line including the output terminal 17 that has output the test tone signal. The detection result by the speaker diagnosis system 21 is output to the CPU 10.
As in the first embodiment, when a speaker is connected to the output terminal 17 from which the test tone signal is output (corresponding to a case where a predetermined load is connected), the speaker line including the output terminal 17 is connected. A current of a predetermined value flows.
The CPU 10 determines whether or not a speaker is connected to the output terminal 17 based on whether or not a current value corresponding to the test tone signal is detected by the speaker diagnosis system 21. Based on the determination result, the CPU 10 connects to the audio device 1A. The arrangement of the speakers is determined (step ST2a). Here, the speakers are arranged in two channels of left and right FL / FR on the front seat side shown in FIG. 3A, and left and right FL / FR on the front seat side and rear seat side shown in FIG. Either the left / right RL / RR four-channel speaker arrangement or an external amplifier is connected.
Therefore, when the CPU 10 determines that the speakers are connected to the two output terminals 17 based on the detection result by the speaker diagnosis system 21, the CPU 10 determines that the speaker arrangement of the left and right channels on the front seat side is four. If it is determined that a speaker is connected to the output terminal 17, it is determined that the left and right speakers on the front seat side and the left and right channel speakers on the rear seat side are arranged in four channels.
Further, when it is determined that the speaker, that is, the current corresponding to the load does not flow and the speakers are not connected to all the output terminals 17 (all channels open), an external amplifier is connected to the output terminal 17. It is determined that

Subsequent steps ST3a-1, ST3a-2 and ST3a-3 are the same processes as steps ST3-1, ST3-2 and ST3-3 shown in FIG. 2 of the first embodiment. The description is omitted.

As described above, according to the second embodiment, the speaker diagnosis system that is a self-diagnosis system that generates a test tone signal and outputs the test tone signal to the output terminal 17 and detects the current at the output terminal 17 that has output the test tone signal. 21, the CPU 10 determines whether or not a speaker is connected to the output terminal 17 based on whether or not the speaker diagnosis system 21 detects a current value corresponding to the test tone signal, and the speaker arrangement is determined based on the determination result. Is determined. As described above, even if the speaker diagnosis system 21 is provided as one function of the power amplifier 15A without mounting the current detection circuit 16, the same effect as in the first embodiment can be obtained.

In the first embodiment, the current detection circuit 16 is provided, and in the second embodiment, the speaker diagnosis system 21 is provided. However, any detection unit that detects a speaker connected to the output terminal 17 may be used. However, it is not limited to these. For example, the presence or absence of speaker connection may be detected by measuring the impedance of the load.

In the present invention, within the scope of the invention, any combination of each embodiment, any component of each embodiment can be modified, or any component can be omitted in each embodiment. .

The audio device according to the present invention can automatically set the frequency and phase characteristics of the output sound in accordance with the arrangement of the speakers without performing a specific operation by the user. It is suitable for an on-vehicle audio device to be arranged.

1, 1A audio device, 10 CPU, 11 storage device, 12 audio playback device, 13 DSP, 14 oscillator, 15, 15A power amplifier, 16 current detection circuit, 17 output terminal, 18 user interface unit, 19 display unit, 20 operation , 21 Speaker Diag System.

Claims

In an audio device including an output terminal connected to a speaker arranged at a predetermined position, which outputs an amplified audio signal to an amplifier,
A storage unit for storing frequency characteristics and phase characteristics of an audio signal corresponding to the arrangement of the speakers;
A detection unit for detecting a speaker connected to the output terminal;
A signal processing unit that processes an audio signal so as to have a set frequency characteristic and phase characteristic and outputs the signal to the amplifier;
The arrangement of the speakers is determined based on the detection result by the detection unit, and the frequency characteristic and phase characteristic of the audio signal corresponding to the determined arrangement are read from the storage unit and set in the signal processing unit. An audio device comprising: a control unit that controls the amplifier in response.
A signal generator that generates a test tone signal and outputs the test tone signal to the output terminal,
The detection unit includes a current detection unit that detects a current at the output terminal that outputs the test tone signal.
The control unit determines whether or not the speaker is connected to the output terminal based on whether or not a current value corresponding to the test tone signal is detected by the current detection unit, and the speaker arrangement is determined based on the determination result. The audio device according to claim 1, wherein the audio device is discriminated.
The detection unit is a self-diagnosis system that generates a test tone signal and outputs the test tone signal to the output terminal, and detects a current in the output terminal that outputs the test tone signal.
The control unit determines whether or not the speaker is connected to the output terminal based on whether or not a current value corresponding to the test tone signal is detected by the self-diagnosis system. The audio apparatus according to claim 1, wherein the arrangement is determined.
The storage unit stores frequency characteristics and phase characteristics of an audio signal output via an external amplifier,
When the control unit determines that the speaker is not connected to all output terminals based on the detection result of the detection unit, the control unit determines that the external amplifier is connected to the output terminal, and 2. The audio according to claim 1, wherein frequency characteristics and phase characteristics of a corresponding audio signal are read from the storage unit and set in the signal processing unit, and the amplifier is controlled according to connection of the external amplifier. apparatus.