CN106911980A - Head circuit with adjustable feedback formula active noise reduction level - Google Patents
Head circuit with adjustable feedback formula active noise reduction level Download PDFInfo
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- CN106911980A CN106911980A CN201710124524.5A CN201710124524A CN106911980A CN 106911980 A CN106911980 A CN 106911980A CN 201710124524 A CN201710124524 A CN 201710124524A CN 106911980 A CN106911980 A CN 106911980A
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- Prior art keywords
- gain
- adjustable
- amplifier
- filter
- signal
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Classifications
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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
- H04R1/00—Details of transducers, loudspeakers or microphones
- H04R1/10—Earpieces; Attachments therefor ; Earphones; Monophonic headphones
- H04R1/1083—Reduction of ambient noise
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10L—SPEECH ANALYSIS OR SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING; SPEECH OR AUDIO CODING OR DECODING
- G10L21/00—Processing of the speech or voice signal to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility
- G10L21/02—Speech enhancement, e.g. noise reduction or echo cancellation
- G10L21/0208—Noise filtering
- G10L21/0216—Noise filtering characterised by the method used for estimating noise
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10L—SPEECH ANALYSIS OR SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING; SPEECH OR AUDIO CODING OR DECODING
- G10L21/00—Processing of the speech or voice signal to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility
- G10L21/02—Speech enhancement, e.g. noise reduction or echo cancellation
- G10L21/0316—Speech enhancement, e.g. noise reduction or echo cancellation by changing the amplitude
-
- G—PHYSICS
- G10—MUSICAL INSTRUMENTS; ACOUSTICS
- G10L—SPEECH ANALYSIS OR SYNTHESIS; SPEECH RECOGNITION; SPEECH OR VOICE PROCESSING; SPEECH OR AUDIO CODING OR DECODING
- G10L21/00—Processing of the speech or voice signal to produce another audible or non-audible signal, e.g. visual or tactile, in order to modify its quality or its intelligibility
- G10L21/02—Speech enhancement, e.g. noise reduction or echo cancellation
- G10L21/0208—Noise filtering
- G10L21/0216—Noise filtering characterised by the method used for estimating noise
- G10L2021/02161—Number of inputs available containing the signal or the noise to be suppressed
- G10L2021/02165—Two microphones, one receiving mainly the noise signal and the other one mainly the speech signal
-
- H—ELECTRICITY
- H04—ELECTRIC COMMUNICATION TECHNIQUE
- H04R—LOUDSPEAKERS, MICROPHONES, GRAMOPHONE PICK-UPS OR LIKE ACOUSTIC ELECTROMECHANICAL TRANSDUCERS; DEAF-AID SETS; PUBLIC ADDRESS SYSTEMS
- H04R2201/00—Details of transducers, loudspeakers or microphones covered by H04R1/00 but not provided for in any of its subgroups
- H04R2201/10—Details of earpieces, attachments therefor, earphones or monophonic headphones covered by H04R1/10 but not provided for in any of its subgroups
Abstract
The present invention relates to a kind of head circuit with adjustable feedback formula active noise reduction level, including：Noise inputs part, voice input portion, amplification output par, c；After the noise inputs part is mixed with the voice input portion by adder, signal is amplified by amplifying output par, c, then by signal output；Amplify output par, c and the audio signal of output is back to noise output par, c, form adjustable feedback formula active noise reduction.The present invention is by setting an adjustable amplifier, the problem for making the regulation of adjustable feedback formula active noise reduction level present in prior art, active noise reduction level and music balanced device all be controlled using a gain is resolved, and audio signal gain is not influenceed by reaction type active noise reduction level, simple structure of the present invention, easy to use, lifting earphone acoustical quality is obvious.
Description
Technical field
The present invention relates to head circuit technical field, more particularly to a kind of ear with adjustable feedback formula active noise reduction level
Electromechanical road.
Background technology
In the prior art, the reaction type active noise reduction level of earphone, active noise reduction level and music balanced device are adjusted all
Using same earphone gain, prior art has the drawback that shadow of the music frequency gain by reaction type active noise reduction level
Ring, the tonequality influence on earphone is very big.
Therefore, prior art needs to improve.
The content of the invention
The invention discloses a kind of head circuit with adjustable feedback formula active noise reduction level, being used to make earphone to realize can
The regulation of reaction type active noise reduction level, active noise reduction level and music balanced device is adjusted all to be controlled using a gain, and audio is believed
Number gain is not influenceed by reaction type active noise reduction level.
A kind of head circuit with adjustable feedback formula active noise reduction level provided in an embodiment of the present invention, including：
Noise inputs part, voice input portion, amplification output par, c；
After the noise inputs part is mixed with the voice input portion by adder, by amplifying output par, c pair
Signal amplifies, then by signal output；
The noise inputs part includes microphone, the first filter, and the microphone receives the noise of nature and raises
Sound device returns the mixed signal of sound, and mixed signal is amplified, and forms the noise signal of reaction type active noise reduction, noise signal warp
First filter carries out noise filtering；
The voice input portion includes audio-source, the second filter, after the audio signal of the audio-source is amplified,
To the second filter, the second filter is filtered to audio signal, the audio signal after output filtering for output；
The amplification output par, c includes：Adjustable amplifier, second adder, amplifier, loudspeaker, it is described that noise is defeated
Enter the audio signal mixing of the noise signal and voice input portion of part, export to adjustable amplifier, adjustable amplifier is to mixed
Closing signal carries out adjustable amplification, is then mixed by second adder with the audio signal of audio-source, and output to amplifier is carried out
Amplify, then export to loudspeaker.
In another embodiment based on the above-mentioned head circuit with adjustable feedback formula active noise reduction level of the present invention,
The loudspeaker, the first filter, amplifier, the product of the gain of microphone are A, and the gain of the second filter is B, adjustable amplification
The gain of device is g, then：
The noise gain of system is：
The audio gain of system is：1+B×g；
The overall gain of head circuit is：
In another embodiment based on the above-mentioned head circuit with adjustable feedback formula active noise reduction level of the present invention,
The loudspeaker, the first filter, amplifier, the product of the gain of microphone are A, and the gain of the second filter meets A ≈ B for B,
Then：
In another embodiment based on the above-mentioned head circuit with adjustable feedback formula active noise reduction level of the present invention,
The voice input portion also includes the second adjustable amplifier；
The audio signal of the audio-source is exported after carrying out adjustable amplification to the second adjustable amplifier, by the audio after amplification
Signal input is to the second filter；
The gain of the first adjustable amplifier is set for g1, the gain of the second adjustable amplifier is g2, loudspeaker, the first filtering
Device, amplifier, the product of the gain of microphone are A, and the gain of the second filter is B, then：
The noise gain of system is：
The audio gain of system is：1+B×g2×g1；
The overall gain of head circuit is：
B × g2 × g1 ≈ A × g1 is made, then：
Compared with prior art, the present invention includes advantages below：
Head circuit with adjustable feedback formula active noise reduction level of the invention, by setting an adjustable amplifier,
The regulation of adjustable feedback formula active noise reduction level present in prior art, active noise reduction level and music balanced device is set all to use one
The problem of individual gain control is resolved, and audio signal gain is not influenceed by reaction type active noise reduction level, structure of the present invention
Simply, easy to use, lifting earphone acoustical quality is obvious.
Brief description of the drawings
In order to illustrate more clearly about the embodiment of the present invention or technical scheme of the prior art, below will be to embodiment or existing
There is the accompanying drawing used in technology description to do one simply to introduce.
Fig. 1 is the circuit of one embodiment of the head circuit with adjustable feedback formula active noise reduction level of the invention
Figure.
Fig. 2 is the head circuit with adjustable feedback formula active noise reduction level of the invention when changing with adjustable amplifier
Noise reduction gain oscillogram.
Fig. 3 is the head circuit with adjustable feedback formula active noise reduction level of the invention when changing with adjustable amplifier
Audio gain oscillogram.
Fig. 4 is the head circuit with adjustable feedback formula active noise reduction level of the invention when changing with adjustable amplifier
Circuit overall gain oscillogram.
Fig. 5 is the circuit of another embodiment of the head circuit with adjustable feedback formula active noise reduction level of the invention
Figure.
In figure：Output par, c is amplified in 1 noise inputs part, 2 voice input portions, 3
Specific embodiment
To make the purpose, technical scheme and advantage of the embodiment of the present invention clearer, below in conjunction with the embodiment of the present invention
In accompanying drawing, the technical scheme in the embodiment of the present invention is clearly and completely described, it is clear that described embodiment is only
Only it is a part of embodiment of the invention, rather than whole embodiments.Based on the embodiment in the present invention, ordinary skill
The every other embodiment that personnel are obtained under the premise of creative work is not made, belongs to the scope of protection of the invention.
Fig. 1 is the circuit of one embodiment of the head circuit with adjustable feedback formula active noise reduction level of the invention
Figure, as shown in figure 1, the head circuit with adjustable feedback formula active noise reduction level includes：
Noise inputs part 1, voice input portion 2, amplification output par, c 3；
After the noise inputs part 1 is mixed with the voice input portion 2 by adder, by amplifying output par, c
3 pairs of signals amplify, then by signal output；
The noise inputs part 1 includes microphone, the first filter, and the microphone receives the noise of nature and raises
Sound device returns the mixed signal of sound, and mixed signal is amplified, and forms the noise signal of reaction type active noise reduction, noise signal warp
First filter carries out noise filtering；
The voice input portion 2 includes audio-source, the second filter, and the audio signal of the audio-source is amplified
Afterwards, to the second filter, the second filter is filtered to audio signal, the audio signal after output filtering for output；
The amplification output par, c 3 includes：Adjustable amplifier, second adder, amplifier, loudspeaker, it is described by noise
The audio signal mixing of the noise signal and voice input portion 2 of importation 1, output to adjustable amplifier, adjustable amplifier
Adjustable amplification is carried out to mixed signal, is then mixed by second adder with the audio signal of audio-source, output to amplifier
It is amplified, then exports to loudspeaker.
In the particular embodiment, before the microphone of earphone is placed in loudspeaker, microphone receives the noise of nature and raises
The sound of sound device feedback, the amplifier carried by microphone, the sound that will mix amplifies, because microphone have received loudspeaker
Feedback sound, therefore, the noise section in mixed noise is suppressed, and forms reaction type active noise reduction, due to amplify
Output par, c sets adjustable amplifier, therefore, in noise inputs part, formation is adjustable feedback formula active noise reduction.
It is the open-loop gain A of reponse system to set loudspeaker, the first filter, amplifier, the product of the gain of microphone, the
The gain of tow filtrator is B, and the gain of adjustable amplifier is g, because prior art is with adjustable feedback formula active noise reduction electricity
Flat head circuit is not provided with adjustable amplifier, and it is formed by placing the microphone in earphone cup beside loudspeaker
Reponse system, while reaction type active noise reduction system gain, changes the noise and audio in earphone cup, therefore, it is existing
The noise gain of the head circuit with adjustable feedback formula active noise reduction level of technology is：
The value of A is bigger, and the decay of head circuit is bigger, in order that loudspeaker keeps original head circuit overall gain, sound
Frequency equalization device gain, input offset EQ is designed as：
EQ≈1+A (2)
Therefore, head circuit overall gain is：
But, because the open-loop gain A for changing reponse system needs to redesign input offset gain EQ, and show
The open-loop gain A and input offset gain EQ for having the reponse system of technology are fixed, in an embodiment of the present invention, due to setting
Adjustable amplifier has been put, therefore,
The noise gain of system is：
The audio gain of system is：1+B×g (5)
The overall gain of head circuit is：
It is the open-loop gain A of reponse system to set loudspeaker, the first filter, amplifier, the product of the gain of microphone, the
The gain of tow filtrator meets A ≈ B for B, then：
Thus, loudspeaker is only applicable to can obtain close to former audio gain, and it is less by adjustable amplifier gain g or active
The influence of noise reduction level change.
Fig. 2 is the head circuit with adjustable feedback formula active noise reduction level of the invention when changing with adjustable amplifier
Noise reduction gain oscillogram, as shown in Fig. 2 the variable resistor by adjusting adjustable amplifier, when variable resistor is respectively set to
When high, medium and low three class, with the change of noise signal frequencies, active noise reduction gain changes therewith, noise gain with
The increase of the adjustable resistance of adjustable amplifier and reduce.
Fig. 3 is the head circuit with adjustable feedback formula active noise reduction level of the invention when changing with adjustable amplifier
Audio gain oscillogram, as shown in figure 3, the variable resistor by adjusting adjustable amplifier, when variable resistor is respectively set to
When high, medium and low three class, with the change of audio signal frequency, audio signal gain changes therewith.Can with reference to Fig. 2
Know, when audio signal gain change is big, the gain of noise signal then reduces, and in 0-1KHz, the amplitude of variation of gain is larger, sound
The gain of frequency signal reduces with the reduction of the adjustable resistance of adjustable amplifier, and the gain of noise signal is with adjustable amplifier
Adjustable resistance reduction and increase.
Fig. 4 is the head circuit with adjustable feedback formula active noise reduction level of the invention when changing with adjustable amplifier
Circuit overall gain oscillogram, as shown in figure 4, the variable resistor by adjusting adjustable amplifier, when variable resistor is respectively provided with
When for high, medium and low three class, with the change of mixing frequency signal, system overall gain changes therewith, but, same
Under the mixing frequency signal of sample, the difference of resistance is not obvious to the change of gain, and yield value is than more consistent.
Fig. 5 is the circuit of another embodiment of the head circuit with adjustable feedback formula active noise reduction level of the invention
Figure, as shown in figure 5, the voice input portion 2 also includes the second adjustable amplifier；
The audio signal of the audio-source is exported after carrying out adjustable amplification to the second adjustable amplifier, by the audio after amplification
Signal input is to the second filter；
The gain of the first adjustable amplifier is set for g1, the gain of the second adjustable amplifier is g2, loudspeaker, the first filtering
Device, amplifier, the product of the gain of microphone are A, and the gain of the second filter is B, then：
The noise gain of system is：
The audio gain of system is：1+B×g2×g1 (9)
The overall gain of head circuit is：
B × g2 × g1 ≈ A × g1 is made, then：
A kind of head circuit with adjustable feedback formula active noise reduction level provided by the present invention has been carried out in detail above
Thin to introduce, specific case used herein is set forth to principle of the invention and implementation method, and above example is said
It is bright to be only intended to help and understand the method for the present invention and its core concept；Simultaneously for those of ordinary skill in the art, foundation
Thought of the invention, will change in specific embodiments and applications, and in sum, this specification content is not
It is interpreted as limitation of the present invention.
Finally it should be noted that：The preferred embodiments of the present invention are the foregoing is only, are not intended to limit the invention,
Although being described in detail to the present invention with reference to the foregoing embodiments, for a person skilled in the art, it still may be used
Modified with to the technical scheme described in foregoing embodiments, or equivalent carried out to which part technical characteristic,
All any modification, equivalent substitution and improvements within the spirit and principles in the present invention, made etc., should be included in of the invention
Within protection domain.
Claims (4)
1. a kind of head circuit with adjustable feedback formula active noise reduction level, it is characterised in that including：
Noise inputs part, voice input portion, amplification output par, c；
After the noise inputs part is mixed with the voice input portion by adder, by amplifying output par, c to signal
Amplify, then by signal output；
The noise inputs part includes microphone, the first filter, and the microphone receives the noise and loudspeaker of nature
The mixed signal of sound is returned, mixed signal is amplified, form the noise signal of reaction type active noise reduction, noise signal is through first
Filter carries out noise filtering；
The voice input portion includes audio-source, the second filter, after the audio signal of the audio-source is amplified, output
To the second filter, the second filter is filtered to audio signal, the audio signal after output filtering；
The amplification output par, c includes：Adjustable amplifier, second adder, amplifier, loudspeaker, it is described by noise inputs portion
The audio signal mixing of the noise signal and voice input portion divided, output to adjustable amplifier, adjustable amplifier is believed mixing
Number adjustable amplification is carried out, is then mixed by second adder with the audio signal of audio-source, output to amplifier is amplified,
Then export to loudspeaker.
2. head circuit according to claim 1, it is characterised in that the loudspeaker, the first filter, amplifier, wheat
The product of the gain of gram wind is A, and the gain of the second filter is B, and the gain of adjustable amplifier is g, then：
The noise gain of system is：
The audio gain of system is：1+B×g；
The overall gain of head circuit is：
3. head circuit according to claim 2, it is characterised in that the loudspeaker, the first filter, amplifier, wheat
The product of the gain of gram wind is A, and the gain of the second filter meets A ≈ B for B, then：
4. head circuit according to claim 1 and 2, it is characterised in that the voice input portion can also including second
Adjust amplifier；
The audio signal of the audio-source is exported after carrying out adjustable amplification to the second adjustable amplifier, by the audio signal after amplification
It is input into the second filter；
The gain of the first adjustable amplifier is set for g1, the gain of the second adjustable amplifier is g2, loudspeaker, the first filter,
Amplifier, the product of the gain of microphone are A, and the gain of the second filter is B, then：
The noise gain of system is：
The audio gain of system is：1+B×g2×g1；
The overall gain of head circuit is：
B × g2 × g1 ≈ A × g1 is made, then：
Priority Applications (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710124524.5A CN106911980A (en) | 2017-03-03 | 2017-03-03 | Head circuit with adjustable feedback formula active noise reduction level |
| PCT/CN2017/000312 WO2018157266A1 (en) | 2017-03-03 | 2017-04-24 | Headphone circuit with adjustable feedback-type active noise-reduction level |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN201710124524.5A CN106911980A (en) | 2017-03-03 | 2017-03-03 | Head circuit with adjustable feedback formula active noise reduction level |
Publications (1)
| Publication Number | Publication Date |
|---|---|
| CN106911980A true CN106911980A (en) | 2017-06-30 |
Family
ID=59186541
Family Applications (1)
| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201710124524.5A Pending CN106911980A (en) | 2017-03-03 | 2017-03-03 | Head circuit with adjustable feedback formula active noise reduction level |
Country Status (2)
| Country | Link |
|---|---|
| CN (1) | CN106911980A (en) |
| WO (1) | WO2018157266A1 (en) |
Cited By (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107393545A (en) * | 2017-07-17 | 2017-11-24 | 会听声学科技（北京）有限公司 | A kind of reaction type active noise reduction system and method with flexible gain |
| CN110225429A (en) * | 2019-06-12 | 2019-09-10 | 会听声学科技（北京）有限公司 | Active denoising method, device and earphone |
| CN110446146A (en) * | 2019-08-07 | 2019-11-12 | 常州科先达通讯技术有限公司 | Smart speakers |
| CN111295707A (en) * | 2017-10-30 | 2020-06-16 | 伯斯有限公司 | Compression hear-through in personal acoustic devices |
| CN111461438A (en) * | 2020-04-01 | 2020-07-28 | 中国人民解放军空军93114部队 | Signal detection method and device, electronic equipment and storage medium |
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| CN101765041A (en) * | 2009-06-09 | 2010-06-30 | 北京中星微电子有限公司 | Audio-frequency playing equipment and method for reducing environmental noises generated during audio-frequency playing |
| WO2016032523A1 (en) * | 2014-08-29 | 2016-03-03 | Harman International Industries, Inc. | Auto-calibrating noise canceling headphone |
| CN106465007A (en) * | 2014-03-28 | 2017-02-22 | ams有限公司 | Control circuit for active noise control and method for active noise control |
| CN206533513U (en) * | 2017-03-03 | 2017-09-29 | 富士高实业有限公司 | Head circuit with adjustable feedback formula active noise reduction level |
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2017
- 2017-03-03 CN CN201710124524.5A patent/CN106911980A/en active Pending
- 2017-04-24 WO PCT/CN2017/000312 patent/WO2018157266A1/en active Application Filing
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| Publication number | Priority date | Publication date | Assignee | Title |
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| CN101208742A (en) * | 2005-05-18 | 2008-06-25 | 伯斯有限公司 | Adapted audio response |
| CN101765041A (en) * | 2009-06-09 | 2010-06-30 | 北京中星微电子有限公司 | Audio-frequency playing equipment and method for reducing environmental noises generated during audio-frequency playing |
| CN106465007A (en) * | 2014-03-28 | 2017-02-22 | ams有限公司 | Control circuit for active noise control and method for active noise control |
| WO2016032523A1 (en) * | 2014-08-29 | 2016-03-03 | Harman International Industries, Inc. | Auto-calibrating noise canceling headphone |
| CN206533513U (en) * | 2017-03-03 | 2017-09-29 | 富士高实业有限公司 | Head circuit with adjustable feedback formula active noise reduction level |
Cited By (7)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| CN107393545A (en) * | 2017-07-17 | 2017-11-24 | 会听声学科技（北京）有限公司 | A kind of reaction type active noise reduction system and method with flexible gain |
| CN111295707A (en) * | 2017-10-30 | 2020-06-16 | 伯斯有限公司 | Compression hear-through in personal acoustic devices |
| CN111295707B (en) * | 2017-10-30 | 2024-04-09 | 伯斯有限公司 | Personal acoustic device compressed hearing aid in (a) |
| CN110225429A (en) * | 2019-06-12 | 2019-09-10 | 会听声学科技（北京）有限公司 | Active denoising method, device and earphone |
| CN110446146A (en) * | 2019-08-07 | 2019-11-12 | 常州科先达通讯技术有限公司 | Smart speakers |
| CN111461438A (en) * | 2020-04-01 | 2020-07-28 | 中国人民解放军空军93114部队 | Signal detection method and device, electronic equipment and storage medium |
| CN111461438B (en) * | 2020-04-01 | 2024-01-05 | 中国人民解放军空军93114部队 | Signal detection method and device, electronic equipment and storage medium |
Also Published As
| Publication number | Publication date |
|---|---|
| WO2018157266A1 (en) | 2018-09-07 |
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