A kind of off beat muffling device for musical instrument sound chamber
Technical field
The present invention relates to a kind of off beat silencing means, be particularly well-suited to the small-sized airtight or semi-open space in similar musical instrument sound chamber.
Background technology
Currently with the improvement of people's living standard and the attention to minor's quality-oriented education, substantial amounts of child, teenager with
And adult starts to set foot in the music learning of musical instrument class.But most people is not because having between the exercise of specialty and the time, often selects
Stay at home and the non-working time carries out musical instrument exercise.This causes a negative impact is exactly to produce the noise disturbing residents.Even
Between professional exercise, because exercise number increases also can produce mutual interference reduction exercise efficiency.How effectively to control
The volume of musical instrument becomes an a technical difficult problem even social concern.
Because every kind of musical instrument has the principle of sound of himself uniqueness to want acoustical demands, utilize physical method off beat noise reduction often cost big
And poor efficiency.The present invention make use of musical sound to belong to the characteristic of mechanical wave cleverly, utilizes electrical principles to complete off beat erasure effect.
Content of the invention
In view of physical method is mainly taked in current musical instrument off beat noise reduction, cost is big and efficiency is low.It is an object of the invention to overcome now
There is the deficiency of conventional off beat sound-silencing measures, provide a kind of general and effective, go for the electricity of most Self-sounding musical instrument
Sub-off beat muffling device.It takes full advantage of the principle that sound wave belongs to mechanical wave, and pickup artificially manufacture and source of sound are same frequently, anti-phase
The sound wave that offsets offset and weaken original sound wave to reach the purpose of off beat noise reduction.
It is an object of the invention to be achieved through the following technical solutions: for the off beat muffling device in musical instrument sound chamber, it utilizes spy
Survey microphone pickup audio signal, after signal is carried out suitable amplification, pass to audio codec;Audio codec is at MCU
Under audio processing algorithms control in computing module, generation offsets audio signal with former audio frequency with same frequency and reversed-phase;Offset audio signal
Regulated the intensity of final output signal by o controller and amplifier, and pass to noise elimination loudspeaker;Noise elimination loudspeaker will offset audio frequency letter
Number output offsets former audio frequency.Meanwhile, the present invention also provides monitoring headpone passage, is used for the sound before monitoring off beat noise reduction, and
Simultaneously provide the noise reduction impurity elimination function to this audio signal.
Simultaneously, present invention also offers the ability that equipment interconnects with other smart machines, particularly coordinate exploitation with it
Mobile phone A PP and pc client remotely control and information mutual communication ability can be provided, even provide the connection energy between different musical instrument
The basis that power and SNS social networks are set up.
The invention has the beneficial effects as follows:
(1) it is designed with detection microphone, by the original audio signal of this microphone pickup 60Hz to 2000Hz, these audio frequency
Signal covers the discernmible most sound frequencies of general human ear;
(2) being designed with audio frequency control processing module, this module can complete the process of original audio signal, and is within it built in MCU
Processing Algorithm control under, complete to produce the new audio signal contrary with original audio signal frequency same phase sending and put outward.With
When deliver to after the audio frequency before off beat noise reduction can be carried out noise reduction impurity elimination process outer put equipment;
(3) in audio frequency control processing module, be also devised with o controller, can manually or programme-control regulation output audio frequency letter
Number intensity, to complete controlled off beat erasure effect;
(4) it is designed with terminal connecting module, this equipment can be enable to connect the smart machine with smart mobile phone as representative or with PC
Machine is the other-end equipment of representative, and can be operated equipment by the interface of design.In such a way by this equipment
Also become a smart machine, and have the ability to carry out exchanging with the external world, respond.
(5) being designed with indicating lamp module, the order that indicator lamp array is come by response MCU can carry out various characteristic response, complete
Become and extraneous visual interactive.
(6) internal battery and charging module, it is ensured that this equipment can be independent, powers for a long time, to support that this equipment has completed
Benefit function.
Brief description
Fig. 1 is the application scenarios schematic diagram of the present invention;
Fig. 2 is the total system composition schematic diagram of the present invention;
Fig. 3 is the circuit theory schematic diagram of audio frequency control computing module of the present invention;
Fig. 4 is the circuit theory schematic diagram of the terminal connecting module of the present invention;
Fig. 5 is the circuit theory schematic diagram of the indicating lamp module of the present invention;
Fig. 6 is the circuit theory schematic diagram of the power management module of the present invention;
Modules assembly has carried out numbering mark in the drawings.
Detailed description of the invention
Below in conjunction with the accompanying drawings and embodiment describes in further detail technical scheme, but protection scope of the present invention is not limited to
In the following stated.
The equipment of [embodiment 1] present invention makes to be installed on typical case in various manners such as: 500 millimeters (length) * 500 millimeters (wide)
*, in the small enclosed of 200 millimeters (high) and hemi-closure space, the whole available function of system is as shown in Figure 1.
System, when actually used, picks up the audio frequency in above-mentioned space by detection microphone (1) designed in Fig. 1, then
It is sent to the audio operational module shown in Fig. 2.Audio operational module carries out pre-putting (2.1) by detecting the signal sending on microphone (1),
Put output audio signal in advance to export to audio coding decoding module (2.4), MCU computing after automatic growth control (2.2) process
Module (2.3) process according to audio coding decoding module (2.4) after audio frequency parameter, utilize ANC algorithm produce required same frequency,
Anti-phase audio control parameters, and it is transferred to audio coding decoding module (2.4).Audio coding decoding module (2.4) produces required
Concrete audio signal is simultaneously given put outward noise elimination loudspeaker (6) by o controller (2.6) and amplifier (2.5) output.
Audio signal after noise elimination loudspeaker (6) playback process, this signal mixes with the former audio signal in cavity.Because audio frequency
Mechanical wave attribute, can mix superposition with frequency domain audio signal.Because what noise elimination loudspeaker (6) exported is with frequency, antiphase signal, he
Can be overlapped mutually counteracting.Utilize the signal that o controller (2.6) output intensity is different just can realize the work(of off beat or noise reduction
Energy.
Typical case such as: in the small enclosed of 500 millimeters (length) * 500 millimeters (wide) * 200 millimeters (high) and hemi-closure space,
The maximum sound intensity decay that can reach 0~60dB.
Meanwhile, the signal before noise elimination also can be exported by earphone interface after noise reduction impurity elimination.As: monitoring headpone (7).
Equipment is also devised with terminal connecting module (3), this module provides the ability of equipment and extraneous communication.Matched APP
Application, PC end and high in the clouds application can carry out communication by BT communication module (3.1), Wifi communication module (3.2), transmission
Control command and state, and related audio signal also can by this module transfer give other equipment and be uploaded to APP should
With, PC end and high in the clouds application.
Equipment is also devised with indicating lamp module.Can carry out under MCU control various combination indicator lamp output, complete equipment with
The visual interactive of user.
Power management module (5).Carry one piece of rechargeable battery, provide for above-mentioned all modules the power supply of all size to support,
And standard cell phone charger or conventional PC USB port charging can be passed through.This module can also be sent out to MCU computing module (2.3)
Send battery information mutual for system control and user.