CN1031444C - Listening Spatial Characteristic Correction Device - Google Patents
Listening Spatial Characteristic Correction Device Download PDFInfo
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- CN1031444C CN1031444C CN93101452A CN93101452A CN1031444C CN 1031444 C CN1031444 C CN 1031444C CN 93101452 A CN93101452 A CN 93101452A CN 93101452 A CN93101452 A CN 93101452A CN 1031444 C CN1031444 C CN 1031444C
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- listening space
- frequency characteristic
- correcting
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- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R3/00—Circuits for transducers, loudspeakers or microphones
- H04R3/02—Circuits for transducers, loudspeakers or microphones for preventing acoustic reaction, i.e. acoustic oscillatory feedback
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- Health & Medical Sciences (AREA)
- General Health & Medical Sciences (AREA)
- Otolaryngology (AREA)
- Physics & Mathematics (AREA)
- Engineering & Computer Science (AREA)
- Acoustics & Sound (AREA)
- Signal Processing (AREA)
- Circuit For Audible Band Transducer (AREA)
- Tone Control, Compression And Expansion, Limiting Amplitude (AREA)
Abstract
本发明涉及校正由于收听空间的形状及大小引起的频率畸变的装置，特别是预先测定收听空间的各种形状引起的信号畸变特性、建立数据库，从而使使用者可以对各种空间校正畸变的收听空间特性校正装置。还有对收听空间的形状及大小引起的收听空间的信号畸变特性建立数据库，通过使用者的选择可以校正信号的畸变，从而可以排除设置话筒和连接导线的麻烦，省掉话筒等不必要的装置，简化音频设备的设置及构成、降低了成本。
The present invention relates to a device for correcting frequency distortion caused by the shape and size of the listening space, especially measuring the signal distortion characteristics caused by various shapes of the listening space in advance and establishing a database so that the user can correct the distortion for various spaces. Spatial characteristic correction device. There is also a database for the signal distortion characteristics of the listening space caused by the shape and size of the listening space, and the signal distortion can be corrected through the user's choice, so that the trouble of setting up the microphone and connecting wires can be eliminated, and unnecessary devices such as microphones can be saved. , simplify the setting and composition of the audio equipment, and reduce the cost.
Description
The present invention relates to be used to proofread and correct by the shape of listening space and the device of the big or small frequency distortion that causes, particularly measure signal distortion characteristic that the different shape of listening space causes in advance, set up database, the apparatus for adjusting of character of radio wave that the user can proofread and correct various spaces.
Usually, in audio frequency apparatus, be used to write down and reset sound and the CD (cartridge) that uses or DAT (digital audiotape) audio sound of output of resetting, be amplified to the degree that the listener can listen to by power amplifier because of signal is very weak.
The sound that has amplified, by the actual sound of listening of loud speaker output, at this moment, the sound of loud speaker output is because the acoustic characteristic of the listening space at listener place and distortion has difference with actual sound.
The main cause that causes the audio distortions of playback is the shape of listening space and the sound reflection rate of wall.
Therefore, the actual sound of hearing of listener is not the original sound by outputs such as CD or DAT, but because the characteristic of listening space has produced the sound of distortion.
In order to address the above problem, be to listening space output test signal in the past, after grasping the characteristic of listening space,, come distortion to the signal correction sound of the output of resetting by correcting distorted frequency characteristic again according to the characteristic of listening space according to the signal that returns.
Fig. 1 is the block diagram of the apparatus for adjusting of character of radio wave of this correcting frequency characteristic that has earlier.
According to Fig. 1, the apparatus for adjusting of character of radio wave that has earlier is made of signal source 10, stimulus maker 20, frequency mixer 30, equalizer 40, power amplifier 50, loud speaker 60, frequency characteristic detector 80, A/D converter 90 and controller 100, and signal source 10 is used for the sound of playback of recorded on CD or DAT; Stimulus maker 20 produces the stimulus of the audio distortions that characteristics such as being used to proofread and correct listening space causes; Frequency mixer 30 is used for the stimulus that above-mentioned stimulus maker 20 produces is stated from the transmission lines of the audio frequency apparatus of the sound that transmits above-mentioned signal source 10 outputs; Equalizer 40 is used to compensate the frequency characteristic by the signal of above-mentioned frequency mixer 30 outputs; Because the sound of equalizer 40 outputs is more weak, power amplifier 50 is used for the sound of resetting is amplified to the degree that the listener can listen to; Loud speaker 60 is used for the sound that above-mentioned power amplifier 50 amplifies is zoomed into the sound that can listen; Frequency characteristic detector 80 extracts the frequency characteristic of listening space from the stimulus of the microphone 70 that is input to the stimulus that is used for receiving once more loud speaker 60 outputs; It is digital signal that A/D converter 90 is used for the frequency characteristic signal transformation of above-mentioned detection; Controller 100 is used for the signal and the stimulus of 90 outputs of A/D converter are compared, and after the correction signal of generation listening space, exports to equalizer 40, proofreaies and correct the frequency distortion that listening space causes sound.
In the apparatus for adjusting of character of radio wave of above-mentioned formation, audio frequency apparatus is once moving by controller 100 indication stimulus makers 20 output test signals.Above-mentioned stimulus maker 20 is according to the instruction output test signal of controller 100.
At this moment, employed stimulus is generally white noise or pink noise, during special circumstances, uses pulse signal.
By the stimulus of above-mentioned stimulus maker 20 outputs behind frequency mixer 30, by equalizer 40, power amplifier 50 and loud speaker 60 outputs.By the stimulus of above-mentioned loud speaker 60 outputs, distort by the sound reflection rate of the shape of listening space and wall.
As mentioned above, in listening space the stimulus of distortion having taken place, by being arranged on the microphone 70 of listening space ad-hoc location (user listen to position), has been input in the frequency characteristic detector 80.Frequency characteristic detector 80 extracts the frequency characteristic of listening space according to the stimulus of input.
At this moment, be the situation of white noise or pink noise for the stimulus of stimulus maker 20 output, said frequencies behavior detector 80 is checked the frequency part that has reduced.If what use is pulse signal, then, extract the frequency characteristic of listening space by after the signal of importing is carried out fft analysis.The frequency characteristic signal that extracts from frequency characteristic detector 80 is an analog signal, so, by A/D converter 90 it is transformed to digital signal.
To be input to controller 100 by the frequency characteristic signal that A/D converter 90 is transformed into digital signal.After controller 100 compares the former stimulus of the frequency characteristic signal of input and 20 outputs of stimulus maker, extract the transmission characteristic of listening space.Above-mentioned controller 100 is according to the transmission characteristic of the listening space of extracting, calculation correction characteristic.The correcting feature that calculates is outputed to equalizer 40.Equalizer 40 outputs to power amplifier 50 with it after only proofreading and correct the audio sound of being reset, being imported by signal source 10 with the correcting feature of slave controller 100 inputs.
The technology of correcting frequency characteristic in a manner described, United States Patent (USP) No. 4688258 " AU-TOMATIC GRAPHIC BOUALIZER " has been done detailed description.According to above-mentioned patent, generate pink noise after, measure the frequency characteristic of surrounding environment, the frequency characteristic of correct detection, automatically control the frequency characteristic of Graphic equalizer.
But above-mentioned technology because the reflectivity of the characteristic of listening space and wall causes the signal of distortion, must be provided with microphone in order to receive in the position at listener place, so, very bother, and between microphone and audio frequency apparatus, need to connect with other lead.
In addition, because the audio frequency apparatus planted agent is equiped with frequency characteristic detector, A/D converter and is used for the device of calculation correction characteristic, so, cost an arm and a leg.
Therefore, purpose of the present invention aims to provide a kind of apparatus for adjusting of character of radio wave of economy, this device is set up database to the signal distortion characteristic corresponding to the listening space of the shape of listening space and size, can be according to user's selection, the distortion of correction signal, can get rid of and microphone is set is connected the trouble that lead brings, and then can remove unnecessary equipment such as microphone, the setting and the structure of simplification audio frequency apparatus with increasing.
In order to achieve the above object, apparatus for adjusting of character of radio wave of the present invention is made of dc-dc converter, database, controller and correction of frequency characteristic device, and dc-dc converter is used to import the performance data of listening space; Database is used for storing based on the data of the characteristic correction frequency characteristic of listening space and the program of correcting frequency characteristic; Controller is according to the input of above-mentioned dc-dc converter, utilizes above-mentioned database interpretation and exports the performance data and the program of corresponding listening space; The correction of frequency characteristic device utilizes the signal of the performance data audio calibration equipment output of controller according to the program of above-mentioned controller, and exports to power amplifier.
Engage accompanying drawing below and describe the present invention in detail.Wherein
Fig. 1 is the block diagram of the apparatus for adjusting of character of radio wave that has earlier,
Fig. 2～Fig. 5 is the key diagram of the embodiment of apparatus for adjusting of character of radio wave of the present invention, and Fig. 2 is the block diagram of device of the present invention, and Fig. 3 is the block diagram of one embodiment of the invention, and Fig. 4 is the exemplary plot of the position of spatial form and loud speaker.Fig. 5 a, Fig. 5 b are the circuit diagrams of the means for correcting of Fig. 2 or Fig. 3.
Device of the present invention is measured the correcting feature of decisions such as the shape of listening space and size in advance, and store in the memory, directly select to be suitable for the shape in space, equipment place and the correcting feature of size by the user, with this distortion that comes the listening space of adjusted weight sound reproduction sound to cause.
According to Fig. 2, the apparatus for adjusting of character of radio wave of present embodiment is made of signal source 10, dc-dc converter 110, database 120, controller 130, display 140, correction of frequency characteristic device 150, power amplifier 50 and loud speaker 60.Signal source 10 is used for playback of recorded as the sound on the recording medium of audio frequency apparatuses such as CD or DAT; Dc-dc converter 110 is by the performance data of user in order to the input listening space; Database 120 is used for storing the frequency characteristic data of characteristic decision of listening space and the program of compensating frequency characteristic; Controller 130 utilizes database 120 interpretations and output to accord with the performance data and the program of listening space according to the input of dc-dc converter 110; Display 140 is according to the control of controller 130, and shape and size by the listening space of dc-dc converter 110 inputs are shown; After correction of frequency characteristic device 150 receives the control signal of controller 130, the replay signal of signal source 10 outputs is compensated the frequency distortion of listening space generation; Power amplifier 50 is amplified to the degree that can listen to frequency characteristic through the replay signal of overcorrect; Loud speaker 60 will be amplified by the sound that power amplifier 50 amplified and become sub-audible sound.
Here, measuring in advance because after the frequency characteristic that the shape of listening space and size distort, being correcting distorted program and storing in advance in the database 120 for the coefficient of emending frequency.
Therefore, the user is at console switch transducer 110, and input is during about the data of the shape of listening space, and controller 130 shows the shape and the size of listening space on display 140 according to the data of input.
In addition, controller 130 accepts to be used to proofread and correct the program of suitable with these input data frequency characteristic that characteristic determined by listening space and coefficient and with its output from database 120.
Correction of frequency characteristic device 150 receives program of proofreading and correct usefulness and the coefficient data that is used for correcting frequency characteristic by controller 130, and the frequency distortion that the replay signal that signal source 10 is exported should produce in listening space is proofreaied and correct back output.
According to Fig. 3, dc-dc converter 110 is made of the 1st switch the 112, the 2nd switch 114 and the 3rd switch 116, during the mode altering of correcting frequency characteristic or user when selecting correction of frequency characteristic to finish, uses the 1st switch 112; Use the 2nd switch 114 when selecting the shape of listening space; Use the 3rd switch 116 when setting listening space big or small.
Correction of frequency characteristic device 150 is made of A/D converter 152, digital signal processor 154 and D/A converter 156, and A/D converter 152 is used for the audio signal of the analog signal of being reset by signal source 10 is transformed to digital signal; Digital signal processor 154 is handled signal after receiving the program of controller 130 inputs and being used for the coefficient data of correction of frequency characteristic; D/A converter 156 is used for the digital signal of handling with above-mentioned digital signal processor 154 is transformed to analog signal once more.
Therefore, user one presses the 1st switch 112, and controller 130 just detects and confirm to be used to proofread and correct the pattern of the frequency characteristic of listening space decision.
Then, by operate the 2nd switch 114 confirm input listening space shape and confirm the size of the listening space of input by operation the 3rd switch.
During to the end of input of the size of listening space, operating the 1st switch 112 by the operation of above-mentioned the 3rd switch 116 once more, confirming the input of the characteristic of listening space is come to an end by controller 130.
Like this, when utilizing the information of dc-dc converter 110 input listening space, controller 130 is to shape and the big or small data of the LCD of display 140 exciter 142 outputs about listening space.LCD exciter 142 is exported the LCD pumping signal according to the input data of above-mentioned controller 130.
LCD144 is when the pumping signal according to 142 outputs of LCD exciter shows the shape of listening space, with the horizontal vertical size of representing listening space than X: Y.
At this moment, if above-mentioned ratio is 1: 2,2: 1,1: 1 according to the fixed in shape of listening space, then, by 116 inputs of the 3rd switch transverse axis data, just can automatically set big or smallly longitudinally, that is very easily.
Promptly, the listening space that to utilize the 2nd switch 114 to select to have horizontal vertical ratio be 1: 2 shape, utilize the operation of the 3rd switch 116 that lateral set is 5m, just can according to the horizontal vertical ratio of listening space automatically listening space vertically be set at 10m, so just can utilize easily.
On the other hand, in case because above-mentioned user has imported the shape and the size of listening space to the operation of dc-dc converter 110, controller 130 is just read from database 120 and is used to proofread and correct program and the coefficient that meets the frequency characteristic distortion, exports to correction of frequency characteristic device 150 then.
At this moment, according to the shape and the size of above-mentioned listening space, in advance the program that is used for correcting distorted frequency characteristic and be used for the coefficient storage of emending frequency in database 120.
Therefore, when the replay signal of correction of frequency characteristic device 150 input signal sources 10, utilize the emending frequency signal to proofread and correct and export the frequency characteristic that distortion takes place listening space in advance.Wherein, A/D converter 152 is transformed to digital signal to the replay signal from above-mentioned signal source 10 inputs.This is because of the cause of use as the digital filter of the DSP of correcting frequency characteristic.
Like this, be transformed to the replay signal of digital signal, utilization is by among the above-mentioned DSP154 that for example digital filter equifrequent characteristic correction element constitutes, according to emending frequency signal (coefficient) correcting frequency characteristic by controller 130 inputs, by the replay signal of DSP154 correction overfrequency characteristic, utilize D/A converter 156 to be transformed to analog signal once more.
On the other hand, according to Fig. 4, the horizontal vertical ratio of listening space 200 is X: Y.At this moment, usually, the horizontal vertical ratio of optimal shape when listening space preferably is decided to be music appreciating is defined as the horizontal vertical ratio of present room Common Shape, and effect is also fine.
But the present invention is for for simplicity, enumerated as an example to be shown among Fig. 4 (a) and (b), (c) that it is horizontal vertical than (X: the Y) shape of the listening space 200 of 1: 2,2: 1 and 1: 1 respectively.
Therefore, for shape and big or small correcting frequency characteristic, should arrive the emending frequency signal storage that is used for the correcting frequency characteristic distortion in the database 120 in advance according to above-mentioned listening space.
For this reason, in the listening space of above-mentioned shape, the position of loud speaker 202,204 is set in advance in the positive left and right sides, sets listener 206 position then.
In case set listener's position, just microphone is set in this position, detect the frequency characteristic of listening space in advance.
That is to say,, detect the frequency characteristic that causes different distortion according to the shape and the size of the various listening space of setting.The frequency characteristic of Jian Ceing stores in Fig. 2 or the database 120 shown in Figure 3 in advance together with the data of listening space in a manner described.Here, above-mentioned data comprises the program for the action of the data that demonstrate the listening space shape at display 140 and controller 130.
According to Fig. 5, in the present invention,, used digital filter for emending frequency.Usually, discrete system is divided into recursive system and nonrecursive system.
Because the impulse response of nonrecursive system is finite length sequence, so, nonrecursive system is called the FIR system.So digital filter also has two kinds on recursion type and onrecurrent type, the former is called iir filter, and the latter is called the FIR filter.
Because the progression N that satisfies the identical needed filter of filter effect seldom, iir filter shown in Figure 5 has the advantage of the burden of hardware such as reducing memory and coefficient calculator, thereby can be divided into a plurality of frequency bands to the frequency range of signal, adjust the amplification of the signal that each frequency band produces respectively and dwindle.
FIR filter shown in Figure 5 can satisfy the frequency spectrum of linear phase characteristics owing to not needing feedback loop to have safe and reliable strong point, can be widely used in waveform and transmit, and the function that can adjust whole frequency range is simultaneously arranged.
In above-mentioned Fig. 5 a and Fig. 5 b, Z
-1Be delay element,
Be multiplier,
Be adder.
In the present invention, in order to carry out the signal processing in the digital processing circuit, be that example is illustrated with iir filter and FIR wave filter, still, also can handle with other any filter.
In Fig. 6, (a) waveform shown in is an example of the distortion frequency characteristic measured in advance in the specific listening space that the user sets.
Therefore, the user is in order to proofread and correct the frequency characteristic of above-mentioned distortion, in advance the program of the DSP154 of control frequency characteristic corrector 150 and coefficient and be to show that in display 140 storage of above-mentioned listening space shape is in database 120.
In Fig. 6, (b) waveform shown in is a frequency characteristic legend that is used for proofreading and correct the frequency characteristic that has distorted in the specific listening space shown in Fig. 6 a.Therefore, when user's console switch transducer 110 was selected to have the listening space of the distortion frequency characteristic shown in Fig. 6 a, controller 130 was just read the program and the system that are stored in advance in the database 120, and is defeated by correction of frequency characteristic device 150.
So just correction of frequency characteristic device 150 produces the signal with the frequency characteristic shown in Fig. 6 b, according to the characteristic of the listening space shown in Fig. 6 a, output has the regeneration sound of distortion frequency characteristic, gain is depicted as the regeneration sound of constant as Fig. 6 C.
As mentioned above, means for correcting of the present invention, signal distortion characteristic corresponding to the listening space of the shape of listening space and size etc. is set up database, selection by the user, distortion that can correction signal, thus can get rid of the trouble that microphone is set and connect lead, and then deduct unnecessary device such as microphone, make the setting of audio frequency apparatus and constitute and simplify, cost is low.
Though the above only is mentioned to the shape and the size of listening space, also can reach purpose of the present invention by setting up database for the reflectivity of the material that constitutes the space wall.In addition, obviously, can provide various shapes usually about the shape of listening space.
In the above, specific embodiment is described very much, but obviously, in not departing from the scope of the present invention, the present invention can be implemented on the situation of various distortion fully.
Claims (7)
1. the means for correcting of a listening space characteristic, comprise that a playback is stored in the signal source of the sound on the recording medium of a stereo set, one and shows that the display of the shape of described listening space and size and sound described playback are amplified to a power amplifier that makes the predeterminated level that the audience can hear, is characterized in that also comprising:
Dc-dc converter is used to import the performance data of the described listening space at user place;
Database is used to store the data of the frequency characteristic that correction determined by the listening space characteristic and the program of correcting frequency characteristic;
Controller is used for exporting according to the data of above-mentioned dc-dc converter input the performance data and the program of the described listening space of reading at above-mentioned database, and controls shape and the size that shows listening space; And
The correction of frequency characteristic device is used for proofreading and correct the frequency distortion that this listening space produces according to the control signal response of above-mentioned controller from the replay signal of source output.
2. press the means for correcting of the described listening space characteristic of claim 1, it is characterized in that: described dc-dc converter is made of the 1st switch, the 2nd switch and the 3rd switch, when the mode altering of correcting frequency characteristic or user when selecting correction of frequency characteristic to finish, use the 1st switch; The 2nd switch is used for selecting the shape of listening space; The 3rd switch is used for setting the size of listening space.
3. by the means for correcting of the described listening space characteristic of claim 1, it is characterized in that: described device comprises the display that is used to show by the performance data of the listening space of dc-dc converter input.
4. press the means for correcting of claim 1 and 3 described listening space characteristics, it is characterized in that: in order to proofread and correct the frequency characteristic that is determined by the shape of listening space and size, database storage the emending frequency (coefficient) measured in advance and the control program that is used for the correction of frequency characteristic device of correcting frequency characteristic.
5. press the means for correcting of the described listening space characteristic of claim 1, it is characterized in that: described correction of frequency characteristic device is made of A/D converter, digital signal processor and D/A converter, and described A/D converter is used for an analog signal and is transformed to digital signal as audio signal; Described digital signal processor processes is by the numerical data and the frequency signal of controller input, and with correcting frequency characteristic, described D/A converter is used for corrected replay signal is transformed to analog signal.
6. by the means for correcting of the described listening space characteristic of claim 5, it is characterized in that: described digital signal processor is made of the recursion type iir filter.
7. by the means for correcting of the described listening space characteristic of claim 5, it is characterized in that: described digital signal processor is made of onrecurrent type FIR filter.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| KR1019920003261A KR970005607B1 (en) | 1992-02-28 | 1992-02-28 | Listening space characteristic correction device |
| KR92-3261 | 1992-02-28 |
Publications (2)
| Publication Number | Publication Date |
|---|---|
| CN1076072A CN1076072A (en) | 1993-09-08 |
| CN1031444C true CN1031444C (en) | 1996-03-27 |
Family
ID=19329716
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN93101452A Expired - Fee Related CN1031444C (en) | 1992-02-28 | 1993-02-11 | Listening Spatial Characteristic Correction Device |
Country Status (3)
| Country | Link |
|---|---|
| JP (1) | JPH0686380A (en) |
| KR (1) | KR970005607B1 (en) |
| CN (1) | CN1031444C (en) |
Families Citing this family (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JP2001086600A (en) * | 1999-09-17 | 2001-03-30 | Nec Home Electronics Ltd | Surround system |
| JP4366040B2 (en) | 2002-03-07 | 2009-11-18 | インターナショナル・ビジネス・マシーンズ・コーポレーション | Network service system, server and program |
| US7170342B2 (en) | 2002-12-10 | 2007-01-30 | Ntt Docomo, Inc. | Linear power amplification method and linear power amplifier |
| KR20060022968A (en) | 2004-09-08 | 2006-03-13 | 삼성전자주식회사 | Sound Regeneration Device and Sound Regeneration Method |
| KR101764660B1 (en) | 2013-03-14 | 2017-08-03 | 애플 인크. | Adaptive room equalization using a speaker and a handheld listening device |
| KR101373077B1 (en) * | 2013-09-17 | 2014-03-12 | 온시스텍 주식회사 | Real time audio sound correction system |
| CN111565352B (en) * | 2014-09-09 | 2021-08-06 | 搜诺思公司 | Method performed by computing device, playback device, calibration system and method thereof |
Family Cites Families (1)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| JPH0667027B2 (en) * | 1984-10-01 | 1994-08-24 | ソニー株式会社 | Automatic sound field correction device |
-
1992
- 1992-02-28 KR KR1019920003261A patent/KR970005607B1/en not_active Expired - Fee Related
-
1993
- 1993-01-26 JP JP5010956A patent/JPH0686380A/en active Pending
- 1993-02-11 CN CN93101452A patent/CN1031444C/en not_active Expired - Fee Related
Also Published As
| Publication number | Publication date |
|---|---|
| KR970005607B1 (en) | 1997-04-18 |
| CN1076072A (en) | 1993-09-08 |
| JPH0686380A (en) | 1994-03-25 |
| KR930019062A (en) | 1993-09-22 |
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