CN103428592A - Sound amplifying device - Google Patents

Abstract

The invention discloses a sound amplifying device which comprises a shell, an induction coil arranged in the shell, a pre-amplification equalizer connected with the induction coil, an audio power amplifier connected with the pre-amplification equalizer, a loudspeaker connected with the audio power amplifier and a power module, wherein the pre-amplification equalizer, the audio power amplifier and the loudspeaker are all powered by the power module, the induction coil is arranged close to the inner wall of the shell and used for inducing an audio electromagnetic signal from the outside, and the loudspeaker is arranged at an opening of the shell. Compared with the traditional loudspeaker connected in a wireless mode, the loudspeaker has the advantages of low power consumption, low cost, simplicity in operation and even no need of manual operation.

Description

PA device

【Technical field】

The invention relates to audio amplification, in particular to a sound amplification device.

【Background technique】

Mobile electronic devices such as mobile phones, tablet computers, music or media players generally have built-in speakers, but limited to the size of the mobile electronic device itself, the built-in speakers are usually relatively small, so the output volume is also relatively small. Therefore, mobile electronic devices all need a loudspeaker device to increase the volume output as an auxiliary device.

The sound amplifying device can be connected to the mobile electronic device by wire, so that the audio signal of the mobile electronic device is transmitted to the sound amplifying device through the signal line, and the sound amplifying device performs amplifying processing and outputs it. However, wired connections always bring more inconvenience.

The sound amplifying device can also be connected with mobile electronic equipment in a wireless manner. The standard wireless connection method needs to adopt relatively complex circuits, and has relatively high energy consumption, which will increase the cost of the PA device.

【Content of invention】

Based on this, it is necessary to provide a low-cost and easy-to-use loudspeaker device for mobile electronic devices with built-in small speakers.

A kind of loudspeaker device, comprising a shell, also includes an induction coil placed in the shell, a preamplifier equalizer connected with the induction coil, an audio power amplifier connected with the preamplifier equalizer, and the The speaker connected to the audio power amplifier and the power module, the preamplifier equalizer, the audio power amplifier and the speaker are all powered by the power module, and the induction coil is set close to the inner wall of the casing for sensing the audio from the mobile electronic device For electromagnetic signals, the horn is arranged at the opening of the casing.

Preferably, a central processing module is also included, and the preamplifier equalizer, audio power amplifier and power supply module are all connected to the central processing module, and the central processing module is controlled according to whether the preamplifier equalizer detects an audio electromagnetic signal The audio power amplifier is turned on or off.

Preferably, the number of the induction coils is more than two and they are distributed at different positions on the inner wall of the casing.

Preferably, a multiplexer switch connected between the induction coil and the preamplifier equalizer is also included.

Preferably, the multiplex switch is manually set.

Preferably, the multiplex switch is connected to the central processing module, and is automatically configured by the central processing module.

Preferably, the output end of the audio power amplifier is also connected to a coil for transmitting electromagnetic signals.

Preferably, the induction coil is movably arranged on the inner wall of the housing.

Preferably, it also includes a sound reflector provided outside the housing.

Preferably, an anti-phase induction coil for eliminating ambient noise is also included.

The above-mentioned sound amplifying device, because only a small amount of induction coils and basic preamplifier equalizers and audio power amplifiers are used, has low cost and does not cause large energy loss during use. In addition, as long as the mobile electronic device is brought close to the sound amplifying device, and the speaker of the electronic device is brought close to the induction coil, the audio electromagnetic signal emitted by the speaker of the electronic device is sensed and amplified, so the operation is very simple.

【Description of drawings】

Fig. 1 is a structural diagram of the sound reinforcement system module of an embodiment;

The exterior view of the public address system of Fig. 2 Fig. 1 embodiment;

Fig. 3 is the structural diagram of the sound reinforcement system module of another embodiment;

Fig. 4 (a) and Fig. 4 (b) are state diagrams when the tablet computer utilizes the sound amplifying device of the embodiment of Fig. 3 to amplify sound;

Fig. 5 is a schematic diagram of the distribution of multiple induction coils in the loudspeaker device in the embodiment of Fig. 3;

Fig. 6 is the structural diagram of the sound reinforcement system of yet another embodiment;

Fig. 7 is a structural diagram of a cascadable sound amplification device module;

Fig. 8 is a block diagram of a sound amplifying device with an anti-phase induction coil for eliminating ambient noise.

【Detailed ways】

As shown in FIG. 1 , it is a structural diagram of a sound reinforcement system module of an embodiment. The system includes a mobile electronic device 1 and a sound amplification device 2 . The mobile electronic device 1 has a built-in speaker 11 for outputting the sound of the mobile electronic device 1 . The mobile electronic device 1 and the sound amplifying device 2 are close to each other. When the mobile electronic device 1 outputs sound through the speaker 11, a changing electromagnetic field will be generated nearby. The sound amplifying device 2 uses the induction coil 21 to induce and receive the changing electromagnetic field, and passes through The frequency response of the electromagnetic field signal is compensated by processing such as amplification and filtering, and then audio amplification is performed to amplify the sound output by the mobile electronic device 1 .

The mobile electronic device 1 may be, for example, a mobile phone, an audio/video player, a handheld game console or a mobile computer. It has at least one horn 11 inside.

Referring to FIG. 2 , specifically, the sound amplification device 2 includes a housing 201 , an induction coil 21 placed in the housing, a preamplifier equalizer 22 , a central processing module 23 , an audio power amplifier 24 , a speaker 25 and a power supply module 26 . The induction coil 21 , the preamplifier equalizer 22 , the audio power amplifier 24 and the speaker 25 are electrically connected in sequence. The central processing module 23 is connected with the preamp equalizer 22 and the audio power amplifier 24 at the same time. The power supply module 26 supplies power to the preamp equalizer 22 , the central processing module 23 , the audio power amplifier 24 and the speaker 25 .

When the loudspeaker device 2 is used to amplify the volume of the mobile electronic device 1, the position of the speaker of the mobile electronic device 1 should be placed close to the induction coil 21, and the induction coil 21 is coupled with the internal coil of the speaker 11, thereby inductively receiving the signal generated by the audio signal. electromagnetic field signal. The induction coil 21 is preferably a coil capable of receiving electromagnetic signals of most audio frequencies.

The preamplifier equalizer 22 is used to amplify and filter the signal obtained by the induction coil 21 and then output it to the audio power amplifier 24 . The audio signal output by the audio power amplifier 24 is output by the speaker 25 . The audio electromagnetic signal obtained by the preamplifier equalizer 22 from the speaker 11 of the mobile electronic device 1 may come from various sounds, speech, music, etc., and may also be a coded and compressed audio signal. The preamplifier equalizer 22 is preferably a DSP (Digital Signal Process, digital signal processing) module, and the DSP module has more precise equalization control and can make the entire audio system have a smoother frequency response. Because the size of the speaker 11 in the mobile electronic device 1 cannot be made very large, low frequency signals are usually filtered out. The DSP module can regenerate the low-frequency signal filtered out at the mobile electronic device 1 to obtain a more complete sound signal.

The audio signal of the mobile electronic device 1 can also be a coded signal, which includes a wider frequency range. The frequency of the coded signal is suitable for transmission through the mobile electronic device 1, and the low frequency components in the sound signal will not be filtered out. The pre-amplifier equalizer 22, which is preferably a DSP module, decodes the encoded signal to obtain the original sound signal.

The central processing module 23 can be used as a power controller of the sound amplification device 2, that is, automatically controls the audio power amplifier 24 to start or close. When the mobile electronic device 1 is close to the sound amplifying device 2 , the central processing module 23 receives the induction signal from the preamp equalizer 22 and analyzes the induction signal. According to the analysis result, the central processing module 23 sends a corresponding control signal to activate the audio power amplifier 24 . When the mobile electronic device 1 is far away from the sound amplifying device 2 , the central processing module 23 knows that the preamplifier equalizer 22 has not detected an electromagnetic signal, and sends a corresponding control signal to turn off the audio power amplifier 24 .

The central processing module 23 can also receive audio electromagnetic signals carrying control commands from the mobile electronic device 1 . The control commands include volume adjustment, balance control, and the like. After these control commands are decoded and analyzed by the central processing module 23, they are used to control and adjust the preamp equalizer 22, the audio power amplifier 24 and other modules.

As shown in FIG. 3 , it is a structural diagram of a sound reinforcement system module in another embodiment. Based on the above embodiments, the system additionally adds a plurality of induction coils 21 and a multiplexer switch 28 connected between the induction coils 21 and the preamplifier equalizer 22 .

For different mobile electronic devices 1 , the positions of the speakers 11 are different. When the placement postures are different, the relative positions of the speakers 11 and the induction coil 21 of the sound amplifying device 2 will also change. In order to achieve the best sound amplification effect, the loudspeaker 11 and the induction coil 21 must be as close as possible to the maximum. When the positions of the speaker 11 of the mobile electronic device 1 and the induction coil 21 of the sound amplifying device 2 are fixed, in order to achieve the best sound amplifying effect, the relative positions of the mobile electronic device 1 and the sound amplifying device 2 must be constantly adjusted, which is harmful to the user. It is more troublesome to say.

By adding additional induction coils 21 and distributing the induction coils at different positions of the housing 201 , making the mobile electronic device 1 and the sound amplification device 2 at different relative positions can also achieve a better sound amplification effect.

As shown in FIG. 4( a ) and FIG. 4( b ), it is a state diagram of the tablet computer using the sound amplifying device of this embodiment to amplify the sound. Figure 4(a) is a diagram of the use state when the tablet computer is placed vertically, and Figure 4(b) is a diagram of the use state when the tablet computer is placed horizontally.

As shown in Fig. 5, a plurality of induction coils 21 are arranged inside the sound amplifying device 2, which can make the induction coils 21 close to the built-in speakers of the tablet computer when the tablet computer is placed horizontally and vertically, so that a good sound amplification effect is provided. .

The multi-way selector switch 28 is used to control the connection between each induction coil 21 and the preamplifier equalizer 22 to select the induction coil 21 closest to the speaker 11 and prevent other induction coils 21 from causing interference.

The multi-way selector switch 28 can adopt manual setting. For example, a switch connected to the preamplifier equalizer 22 is set for each induction coil 21, and the user connects the induction coil 21 to the preamplifier equalizer 22 in turn by closing the switch in turn and judges which induction coil 21 is working according to the output sound When the sound amplification effect is the best.

The multiplexer 28 can also be configured automatically. The multi-way selector switch 28 is connected to the central control module 23. When the mobile electronic device 1 is placed close to the sound amplifying device 2, the sound amplifying device 2 starts the automatic configuration process, and the central processing module 23 is closed one by one and connected to the induction coil 21 and the preamplifier equalizer. The electronic switch between the equalizer 22 and detect the strength of the signal received by the preamplifier equalizer 22. After all the induction coils 21 are detected, the central processing module 23 can determine which induction coils 21 can receive useful signals and which induction coils 21 cannot receive signals or receive interference signals. The central processing module 23 controls the multiplexer 28 to keep the induction coil 21 capable of receiving useful signals connected to the preamplifier equalizer 22 to complete the automatic configuration process. The above automatic configuration process is a sequential configuration method. In addition, a parallel configuration method can also be adopted, that is, the central control module 23 detects the signals received by all induction coils 21 at the same time, and then determines which induction coils 21 actually receive useful audio signals, thereby controlling the multi-channel selection switch 28 .

The process of starting the automatic configuration of the public address device 2 can also be divided into manual or automatic modes. When the user places the mobile electronic device 1 close to the sound amplifying device 2, the automatic configuration process can be manually started by the user, for example, by pressing a certain button. Alternatively, after the central processing module 23 detects that there is a signal, the automatic configuration process is automatically started.

In yet another embodiment, the induction coil 21 may not be fixed, but movably attached to the inner wall of the casing 201 and controlled to move through a mechanism connected to the outside of the casing 201 . Through this mechanism, the user can adjust the position of the induction coil 21 to match with different mobile electronic devices 1 , which can enhance the versatility of the sound amplifying device 2 from another aspect.

As shown in FIG. 6 , it is a structure diagram of a sound reinforcement system in another embodiment. The system includes a mobile phone, one of the commonly used mobile electronic devices 1 , and a loudspeaker device 2 . The sound amplifying device 2 adds a sound reflector 29 on the basis of the foregoing embodiments. The sound reflector 29 has an arc-shaped reflective surface, and is located at one end away from the speaker 25 of the sound amplifying device 2 , and is usually also at the end of the microphone 12 of the corresponding mobile phone during a hands-free call. When the mobile phone turns on the hands-free function and puts it into the amplifying device 2, the loudspeaker 25 of the amplifying device 2 will play the amplified sound of the mobile phone, making the hands-free conversation clearer. The voice emitted by the user's mouth is reflected by the sound reflector 29 and concentrated and strengthened, so that the sound of the microphone 12 of the mobile phone is enhanced.

Further, as shown in FIG. 7 , on the basis of the above embodiments, the output end of the audio power amplifier 25 is also connected to a coil 31 for transmitting audio electromagnetic signals. By arranging the transmitting coil 31, multiple sound amplification devices 2 can be cascaded to form a sound amplification system with higher output power.

Further, on the basis of the embodiment shown in FIG. 1 , an anti-phase induction coil 41 may also be added. The anti-phase induction coil 41 is disposed inside the casing 201 but away from the speaker 11 of the mobile electronic device 1 . The inverting induction coil 41 is also connected to the preamp equalizer 22 and is differentially connected to the induction coil 21 .

Because induction coil 21 also can receive the electromagnetic noise in the environment, for example power line near induction coil 21, transformer, generator or motor etc. also can produce the noise in the sound frequency range, so add anti-phase induction coil 41 to reduce or cancel ambient noise. The anti-phase induction coil 41 and the induction coil 21 are connected in a differential manner, and the environmental noise signals received by the two are the same because they are placed in parallel, but the phases are reversed when they are combined, so they can cancel each other out. The anti-phase induction coil 41 is far away from the speaker 11 , so only the induction coil 21 receives the audio signal, and the audio signal will not be canceled due to the existence of the anti-phase induction coil 41 .

Compared with traditional wirelessly connected sound amplifying devices, the above-mentioned sound amplifying device has the advantages of low power consumption, low cost, simple operation and even no manual operation.

The above-mentioned embodiments only express several implementation modes of the present invention, and the description thereof is relatively specific and detailed, but should not be construed as limiting the patent scope of the present invention. It should be pointed out that those skilled in the art can make several modifications and improvements without departing from the concept of the present invention, and these all belong to the protection scope of the present invention. Therefore, the protection scope of the patent for the present invention should be based on the appended claims.

Claims (10)

1. A sound amplification device, comprising a shell, is characterized in that it also includes an induction coil placed in the shell, a preamplifier equalizer connected with the induction coil, a preamplifier equalizer connected with the preamplifier equalizer The audio power amplifier, the loudspeaker connected with the audio power amplifier and the power supply module, the preamplifier equalizer, the audio power amplifier and the loudspeaker are all powered by the power supply module, and the induction coil is arranged close to the inner wall of the shell for induction An audible electromagnetic signal from a speaker of an external electronic device, said speaker being located at the opening of the housing. 2. The sound amplification device according to claim 1, further comprising a central processing module, the preamplifier equalizer, audio power amplifier and power supply module are all connected with the central processing module, the central processing The module controls the audio power amplifier to be turned on or off according to whether the preamplifier equalizer detects the audio electromagnetic signal. 3. The sound amplifying device according to claim 2, wherein the number of the induction coils is two or more and they are distributed at different positions on the inner wall of the housing. 4. The sound amplification device according to claim 3, further comprising a multiplexer switch connected between the induction coil and the preamplifier equalizer. 5. The sound amplifying device according to claim 4, wherein the multiplex switch is manually set. 6. The sound amplifying device according to claim 4, wherein the multiplex switch is connected to the central processing module, and is automatically configured by the central processing module. 7. The sound amplifying device according to claim 1, characterized in that, the output end of the audio power amplifier is also connected to a coil for transmitting electromagnetic signals. 8. The sound amplifying device according to claim 1, wherein the induction coil is movably disposed on the inner wall of the housing. 9 . The sound amplifying device according to claim 1 , further comprising a sound reflector disposed outside the housing for converging user voice to a microphone of an external electronic device. 10 . 10. The sound amplifying device according to claim 1, further comprising an anti-phase induction coil for canceling ambient noise.

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