WO2007063772A1

WO2007063772A1 - Signal transmitting apparatus, method thereof, and audio apparatus

Info

Publication number: WO2007063772A1
Application number: PCT/JP2006/323430
Authority: WO
Inventors: Shinjiro Kato; Mitsuo Nakazato; Moriyuki Oshima
Original assignee: Pioneer Corporation
Priority date: 2005-12-01
Filing date: 2006-11-24
Publication date: 2007-06-07

Abstract

A positive-phase D/A converter (221) converts a digital signal of audio data to an analog signal, while a negative-phase D/A converter (222) converts the digital signal of audio data to an analog signal having an opposite phase to the analog signal as converted by the positive-phase D/A converter (221). These analog signals of audio data having positive and negative phases are then equally amplified by a first power amplifier (331) and a second power amplifier (332), respectively, and then outputted to a speaker (400). Even if noise is superimposed on the audio data, the speaker (400) does not sound out any noise components of in-phase but sounds out the audio data having different phases. Thus, the speaker (400) itself functions like a differential amplifier, whereby the noise components can be appropriately removed without degrading the audio characteristics, resulting in an excellent reproduction of the audio data.

Description

Specification

SIGNAL TRANSMISSION DEVICE, METHOD THEREOF, AND SOUND DEVICE

Technical field

The present invention relates to a signal transmission device, a method thereof, and an audio device for converting content data of a digital signal into an analog signal and outputting it from a speaker.

Background art

Conventionally, for example, as an audio device mounted on a vehicle, a configuration in which content data such as music and voice is analog-processed and generated from a speaker has been widely used. These sound devices use a configuration that uses unbalanced transmission of content data, such as a transformer or a ground isolator, or a differential amplifier so that a good sounding state can be obtained. A configuration for performing balanced transmission is known (see, for example, Patent Document 1 or Patent Document 2).

[0003] In the configuration described in Patent Document 1, the voltage of the center tap of the primary coil of the isolated transformer is input to the isolator unit that is interposed between the cassette Z receiver unit and the high-power amplifier. A power control signal generation circuit is provided for detecting the presence or absence of a DC component contained in the output of the cassette / receiver unit and outputting a power control signal to the high power amplifier unit at the subsequent stage.

[0004] However, in the configuration using the transformer as described in Patent Document 1, the entire frequency band in the content data cannot be covered, and the content data to be reproduced is reproduced by limiting the frequency band to a predetermined band. There is a risk that the sound characteristics of the sound will deteriorate. Also, the magnetic domain of the magnet used in the transformer may cause distortion in the reproduced sound characteristics.

[0005] In the configuration described in Patent Document 2, in the case of balanced input, the RCA pin cables on the hot side and the cold side are connected to the first and second signal input terminals of the power amplifier, respectively, and the switching switch is set to the first switch. Switch to position. The hot and cold transmission signals are input to the two input terminals of the differential amplifier, and a signal in which the common-mode noise is greatly suppressed is output. For unbalanced input, connect the RC A pin cable for unbalanced transmission to the first signal input. Connect to the terminal and switch the switch to the 2nd position. The unbalanced transmission signal's hot side and GND side are input to the two input terminals of the differential amplifier, and a signal with a certain amount of in-phase noise suppressed is output.

[0006] However, in the configuration using the differential amplifier as described in Patent Document 2, since the noise is removed by the differential amplifier via the not-amplifier, the circuit configuration is in series. However, there is a risk that the sound will not be able to obtain good sound characteristics due to superimposition of the amplifier and the inherent sound and noise of the amplifier. Also, as in Patent Document 2, it is necessary to convert unbalanced transmission to balanced transmission, and the power amplifier must convert balanced transmission to unbalanced transmission, which requires a large number of amplifiers, and more inherent noise is superimposed. However, good sound characteristics may not be obtained immediately.

Patent Document 1: Japanese Patent Application Laid-Open No. 7-303013

Patent Document 2: JP-A-8-70234

Disclosure of the invention

Problems to be solved by the invention

[0008] As described above, in the configuration using a transformer or the like as described in Patent Document 1, a part of the frequency band of the content data is cut, and distortion due to the magnetic domain occurs, resulting in good sound characteristics. May not be regenerated. In addition, in a configuration using a differential amplifier as described in Patent Document 2, amplifiers and amplifiers are connected in multiple stages in series, and there is a risk that unique noise is superimposed and good sound characteristics cannot be obtained. There is.

In view of such circumstances, the present invention has one object to provide a signal transmission device, a method thereof, and an audio device that can be transmitted favorably without impairing the characteristics of content data. To do.

Means for solving the problem

[0010] The signal transmission device of the present invention includes a positive phase converter that converts digital signal content data into an analog signal, and an analog signal that is opposite in phase to the analog signal that converts the content data by the positive phase converter. A negative phase converter for conversion, and the content data of the analog signal of the positive phase converted by the positive phase converter to amplify the speaker And a negative phase amplifier that amplifies the content data of the analog signal that is reversely sent and converted by the negative phase converter and outputs the amplified content data to the speaker.

[0011] A signal transmission method of the present invention is a signal transmission method for converting digital signal content data into an analog signal and outputting it from a speaker, wherein the digital signal content data is transmitted in the normal phase and in reverse. The analog signal is converted into two analog signals, the converted analog signal content data is amplified by an amplifier, and the amplified analog signal content data is output to the speaker.

[0012] An acoustic device of the present invention includes the signal transmission device of the present invention described above and a speaker that produces content data of an analog signal output from the signal transmission device.

Brief Description of Drawings

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

Explanation of symbols

[0014] 10 …… Chassis

100 …… A sound device as a signal transmission device

221 …… Normal phase digital analog (DZA) converter as normal phase converter 222 …… Reverse phase DZ A converter as negative phase converter

331 …… First power amplifier as a positive phase amplifier

332 …… Second power amplifier as a negative phase amplifier

400 …… Speaker

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In this embodiment, sound data, which is music data or audio data, is described as an example of content data. However, image data such as still image data and video data, and content data in which sound data and image data are mixed are described. Can also be targeted. Moreover, although the structure mounted in vehicles, such as a car, is illustrated, it is not restricted to a car, but vehicles, such as a train, and also ship navigation. It can be used for various types of mobile objects such as air machines, and can also be used in various forms such as homes and commercials installed in houses and buildings. FIG. 1 is a block diagram showing a part of a schematic configuration of an audio device according to an embodiment of the present invention.

[Configuration of Acoustic Device]

In FIG. 1, reference numeral 100 denotes an audio device as a signal transmission device according to an embodiment of the present invention, and the audio device 100 outputs a sound of content data reproduction output device power that outputs sound data as content data of a digital signal. A device that acquires data and outputs or reproduces it as sound, which is mounted on a vehicle (not shown). The acoustic device 100 includes a source device 200, an amplifier device 300, and a speaker 400.

[0017] The content data reproduction / output device includes a drive and a driver for reading digital signal content data recorded on various recording media such as an optical disk, a magnetic disk, a magneto-optical disk, and a memory card. In addition, a configuration may be provided that includes a tuner that receives digital broadcast signals such as terrestrial and satellite waves. Then, the content data reproduction / output device outputs the content data of the digital signal acquired from the recording medium or the broadcast wave to the audio device 100 via a cable (not shown).

[0018] The source device 200 acquires sound data output via a cable from the content data reproduction output device, and appropriately converts it into an analog signal. The source device 200 includes a case body 210 that is formed in a substantially box shape using, for example, a metal plate or a synthetic resin plate. The case body 210 is connected to a content data playback / output device with a cable connected thereto, and a source input terminal (not shown) that obtains output sound data and a source output terminal that forms a pair that outputs the converted analog signal sound data. 211 and 212 are provided. For example, when the sound data has a plurality of channels, the source output terminals 211 and 212 are provided in pairs corresponding to the number of channels. Case body 210 is grounded to chassis 10 of the vehicle.

In addition, the source device 200 includes a normal phase digital-analog (DZA) converter 221 as a normal phase converter and a negative phase DZA converter 222 as a negative phase converter, which are disposed in the case body 210. ing. The positive phase DZA converter 221 converts the sound data of the digital signal input to the input terminal into sound data of an analog signal. Reverse feed DZA The converter 222 converts the sound data of the digital signal input to the input terminal into sound data of an analog signal so that the phase is opposite to the phase converted by the normal phase DZA converter 221. The normal phase DZ A converter 221 and the reverse feed DZA converter 222 are grounded to the case body 210, respectively. That is, the normal phase DZA converter 221 and the reverse feed DZA converter 222 are grounded to the chassis 10 of the vehicle via the case body 210.

Furthermore, the source device 200 includes a first output circuit 231 as a positive phase amplifier and a second output circuit 232 as a negative phase amplifier. The first output circuit 231 and the second output circuit 232 are signals corresponding to input operations with various operating means such as control knobs and switches (not shown) provided on the case body 210 so that the user can appropriately perform input operations. Based on the signal, the sound characteristics of the normal-phase and reverse-phase sound data of the analog signal are adjusted. Specifically, the output volume and sound quality are adjusted. The first output circuit 231 and the second output circuit 232 have the same configuration, and the sound data of the normal phase and the reverse phase are adjusted equally. The first output circuit 231 and the second output circuit 23 2 are connected to a pair of source output terminals 211 and 212, respectively, and output sound data with adjusted sound characteristics to the source output terminals 211 and 212, respectively. To do. Further, the first output circuit 231 and the second output circuit 232 are grounded to the case body 210, respectively. That is, the first output circuit 231 and the second output circuit 232 are grounded to the vehicle chassis 10 via the case body 210.

The amplifier device 300 amplifies the sound data of the analog signal output from the source device 200 as appropriate and outputs it to the speaker 400. The amplifier device 300 includes a housing 310 formed in a substantially box shape using, for example, a metal plate or a synthetic resin plate. The housing 310 is connected to the source device 200 via signal lines 501, 502, and a pair of amplifier input terminals 311, 312 to which the analog signal sound data output from the source device 200 is input, and Amplifier output terminals 321 and 322 are provided for outputting the sound data of the amplified analog signal. The amplifier input terminals 311, 312 and the amplifier output terminals 321, 322 are provided in pairs corresponding to the source output terminals 211, 212, that is, in pairs corresponding to the number of sound data channels. [0022] The amplifier device 300 includes a first power amplifier 331 as a normal phase amplifier and a second power amplifier 332 as a negative phase amplifier, which are disposed in the housing 310. Yes. The first power amplifier 331 appropriately amplifies the sound data of the positive phase analog signal input to the amplifier input terminal 311 and outputs it to the amplifier output terminal 321. The second power amplifier 332 appropriately amplifies the sound data of the reverse phase analog signal input to the amplifier input terminal 312, and outputs it to the amplifier output terminal 322. The first power amplifier 331 and the second power amplifier 332 have the same configuration, and amplify the sound data of the normal phase and the reverse phase respectively. The first power amplifier 331 and the second power amplifier 332 are each grounded to the housing 310. That is, the first power amplifier 331 and the second power amplifier 332 are grounded to the chassis 10 of the vehicle via the housing 310.

Speaker 400 is disposed in the vehicle. The speakers 400 are appropriately arranged in the vehicle in a number corresponding to the number of channels of sound data. The speaker 400 is connected to the amplifier output terminals 321 and 322 of the amplifier device 300 via the wires 511 and 512, respectively. Play the data with sound.

[Operation of acoustic device]

Next, the operation of the acoustic device 100 will be described.

[0025] First, when the user acquires sound data to be reproduced by an appropriate input operation by the content data reproduction output device, the content data reproduction output device outputs the sound data to the source device 200 via a cable (not shown). In the source device 200, the input digital signal sound data is converted into analog signal sound data by the normal phase DZ A converter 221, and the phase converted by the negative phase DZA converter 222 by the normal phase DZA converter 221 is used. Convert to analog phase sound data in reverse phase.

Here, source device 200 and amplifier device 300 are grounded with vehicle chassis 10 as ground. In addition, vehicles are equipped with electrical equipment such as generators and fuel injection devices for driving the vehicle, and electrical equipment such as headlamps and wipers for supporting travel. Grounded to 10. Therefore, the noise voltage from each electrical device is applied to chassis 10 and this noise is applied. The voltage causes a potential difference between the ground position of the source device 200 and the ground position of the amplifier device 300, and this potential difference is superimposed on the sound data of the analog signal. Specifically, if the sound data of the analog signal is Vp and the noise is Vn, the sound data of the normal phase is (Vp + Vn) and the sound data of the reverse phase is (−Vp + Vn).

[0027] Then, the normal-phase sound data and the reverse-phase sound data on which the noise is superimposed are sounded by the first output circuit 231 and the second output circuit 232 according to the setting contents according to the user's input operation. The sound characteristics of the data are adjusted in the same way. The sound data of the normal phase and the reverse phase adjusted by the first output circuit 231 and the second output circuit 232 are output from the source output terminals 211 and 212, and are amplified via the signal lines 501 and 502, respectively. The signals are input to the amplifier input terminals 3 11 and 312 of the apparatus 300, respectively.

[0028] In this amplifier device 300, the first-phase power amplifier 331 and the second-power amplifier 332 amplify the sound data of the input analog signal in the normal phase and the reverse phase, respectively, and the respective amplifier output terminals Output to speaker 400 via wires 511 and 512 from 321, 322 force. At the time of this amplification, as described above, noise is superimposed on the sound data of the analog signal, so that it is relatively amplified together with the noise. Specifically, if the amplification coefficient is K, the normal phase sound data is amplified to (K (Vp + Vn)), and the reverse phase sound data is amplified to (K (one Vp + Vn)). Output to speaker 400.

[0029] The amplified normal phase and reverse phase sound data is not output to the speaker 400 because the noise component is in phase, and the sound data is output substantially at 2 KVp. Become. That is, the speaker 400 itself exhibits the same operation as the differential amplifier.

[Effect of acoustic device]

As described above, in the above-described embodiment, the sound data of the digital signal is converted into an analog signal by the normal phase DZA converter 221, and the phase that is opposite to the phase that is converted by the normal phase DZA converter 221 is reversed to the phase DZA. The converter 222 converts the signal into an analog signal. These converted normal-phase and negative-phase sound data are amplified by the first power amplifier 331 and the second power amplifier 332, respectively, and output to the speaker 400. As a result, even if noise is superimposed on the sound data and amplified, the sound data is converted into a normal phase and a reverse phase, respectively. Only the sound data is generated and the speaker 400 itself functions as a differential amplifier, so that noise can be appropriately removed without impairing the sound characteristics of the sound data, and good sound data can be reproduced.

[0031] Then, the source device 200 that converts the sound data into an analog signal for reproduction by the speaker 400 and the amplifier device 300 that amplifies the sound data are grounded to the chassis 10 of the vehicle on which the speaker 400 is mounted. Therefore, when the analog signal sound data converted by the source device 200 is balanced and transmitted to the amplifier device 300 through the signal lines 501, 502, the source device 200 and the amplifier device 300 force noise voltage is applied to the chassis 10 Even if the noise is superimposed on the sound data to be transmitted in balance and amplified to the noise by the amplifier, the noise can be removed appropriately without impairing the sound characteristics of the sound data. .

[0032] Furthermore, when the chassis 10 that grounds the source device 200 and the amplifier device 300 is a vehicle, a generator or a fuel injection device for driving the vehicle, a head lamp or a wiper for supporting the driving, etc. Since various electric devices are mounted on the vehicle and these electric devices are also grounded to the chassis 10, a noise voltage is applied to the chassis 10, and this noise voltage is superimposed on the sound data transmitted in a balanced manner. Therefore, it is particularly effective for such usage forms.

[0033] Further, the DZA converter is connected in parallel to a state in which the sound data of analog signals having opposite phases are converted into a normal phase DZA converter 221 and a reverse phase DZ A converter 222, and the first of the same configuration is connected in series to these. The first output amplifier 331 and the second power amplifier 332 having the same configuration are connected through the signal lines 501, 502 by connecting the output circuit 231 and the second output circuit 232 of the same, respectively, and adjusting the sound characteristics equally. Are connected in series, and the normal phase sound data and the reverse phase sound data converted by the source device 200 are amplified equally by the amplifier device 300 and output to the speaker 400. For this reason, each sound data in the normal phase and the reverse phase is output to the speaker 400 with the same sound characteristics, so that only the noise in phase is output and the sound characteristics are not impaired and are reproduced appropriately. Can be obtained with a simple configuration.

[Modification of Embodiment] The present invention is not limited to the above-described embodiment, but includes the following modifications as long as the object of the present invention can be achieved.

That is, although described as the acoustic device 100 mounted on the vehicle, as described above, it can be applied to a configuration installed in a house or a building in addition to the acoustic device mounted on various moving bodies.

. In addition, as a configuration to be installed in a house or a building, it is effective for a configuration to be installed on a conductor that is a chassis to which a noise voltage is applied.

[0036] Further, as described above, the power described as the acoustic device 100 for reproducing sound data. For example, various types of content data such as image data can be targeted.

Furthermore, although the source device 200 and the amplifier device 300 have been described as separate configurations, they may be configured to be housed in the same casing.

[0038] The force described by connecting the first output circuit 231 and the second output circuit 232 in series to the positive phase DZ A converter 222 and the negative phase DZA converter 222 is not limited to this configuration. . For example, sound data whose sound characteristics have been adjusted in advance at the time of a digital signal may be converted to an analog signal by a normal phase DZA converter 221 and a negative phase DZ A converter 222 and output to the amplifier device 300. .

[0039] In addition, the specific structure for carrying out the present invention can be appropriately changed to other structures or the like as long as the object of the present invention can be achieved.

[Effect of the embodiment]

As described above, in the above-described embodiment, the sound data of the digital signal is converted into an analog signal by the normal phase DZA converter 221, and the phase that is opposite to the phase that is converted by the normal phase DZA converter 221 is reversed to the phase DZA. The converter 222 converts the signal into an analog signal. These converted normal-phase and negative-phase sound data are amplified by the first power amplifier 331 and the second power amplifier 332, respectively, and output to the speaker 400. For this reason, even if noise is superimposed on the sound data and amplified, the sound data is converted into a normal phase and a reverse phase, so that the noise in the same phase is not produced by the speaker 400, and the sound data is out of phase. Only the sound is produced, and the speaker 400 functions like a differential amplifier, so that noise can be appropriately removed without impairing the sound characteristics of the sound data, and good sound data can be reproduced. Industrial applicability

INDUSTRIAL APPLICABILITY The present invention can be used for a signal transmission device, a method thereof, and an audio device for converting content data of a digital signal into an analog signal and outputting the analog signal.

Claims

The scope of the claims

[1] A normal phase converter that converts digital signal content data into an analog signal, a negative phase converter that converts the content data into an analog signal whose phase is opposite to that of the analog signal converted by the positive phase converter,

A positive phase amplifier that amplifies the content data of the positive phase analog signal converted by the positive phase converter and outputs the amplified content data to a speaker;

A reverse phase amplifier that amplifies the content data of the analog signal that has been reversely converted by the negative phase converter and outputs the amplified content data to the speaker;

A signal transmission device comprising:

[2] The signal transmission device according to claim 1,

Grounded to the chassis where the speaker is installed

A signal transmission device characterized by that.

[3] The signal transmission device according to claim 1 or claim 2,

The positive-phase converter and the negative-phase converter are configured as a source device that is grounded to a chassis in which the speaker is installed, receives the digital signal content data, and outputs an analog signal.

The positive phase amplifier and the negative phase amplifier are grounded to the chassis, connected to the source device via a signal line, amplify content data of the analog signal output from the source device, and output the amplified data to the speaker. Configured as an amplifier device

A signal transmission device characterized by that.

[4] The signal transmission device according to claim 2 or claim 3,

The chassis is part of a vehicle

A signal transmission device characterized by that.

[5] A signal transmission method for converting digital signal content data into an analog signal and outputting it from a speaker.

The digital signal content data is converted into two analog signals of normal phase and reverse transmission, The converted analog signal content data is amplified by an amplifier, and the amplified analog signal content data is output to the speaker.

A signal transmission method characterized by the above.

The signal transmission device according to claim 1,

The ability to generate analog signal content data output from this signal transmission device,

An acoustic device comprising: