CN110868653B

CN110868653B - Loudspeaker protection device and method

Info

Publication number: CN110868653B
Application number: CN201810990843.9A
Authority: CN
Inventors: 祝晓昆
Original assignee: Wuhan Silicon Integrated Co Ltd
Current assignee: Wuhan Silicon Integrated Co Ltd
Priority date: 2018-08-28
Filing date: 2018-08-28
Publication date: 2020-12-25
Anticipated expiration: 2038-08-28
Also published as: CN110868653A

Abstract

The embodiment of the invention provides a loudspeaker protection device and method. The device comprises a temperature protection module; the temperature protection module comprises a first detector, a first gain calculator and a first gain device; the first detector is a root-mean-square detector or a mean-square detector, the input end of the first detector is used for receiving a first audio signal to be processed, and the output end of the first detector is connected with the input end of the first gain calculator; the output end of the first gain calculator is connected with the input end of the first gain calculator; the input end of the first booster is further used for receiving the first audio signal to be processed, and the output end of the first booster is used for outputting the processed first audio signal. According to the embodiment of the invention, gain calculation is carried out according to the root mean square or mean square value of the input audio signal and the corresponding threshold value determined by the rated power of the target loudspeaker, the gain value required by temperature protection is obtained, and gain is carried out through the gain device, so that the temperature protection of the target loudspeaker is realized.

Description

Loudspeaker protection device and method

Technical Field

The embodiment of the invention relates to the field of loudspeaker control, in particular to a loudspeaker protection device and method.

Background

With the popularization and popularity of portable intelligent devices, people have higher requirements on the audio playback effect of portable devices. This requires manufacturers to fully exploit the performance of the speaker under physical space constraints while ensuring that the speaker itself is not damaged by excessive drive.

There are two main factors that cause speaker damage: the first is mechanical damage caused by the horn amplitude frequently exceeding a certain limit, and the second is thermal damage caused by long-time over-temperature work of the horn. Existing protection methods for horn amplitude and temperature can be mainly classified into two categories, namely a protection mechanism based on the amplitude of the input signal of the horn and a protection mechanism based on real-time measurement of the voltage and current values on the horn coil.

Based on the protection mechanism of the amplitude of the input signal of the loudspeaker, the prior art compares the input signal of the loudspeaker with N (N ≧ 2) thresholds of different levels, and the higher the threshold that the input signal exceeds, the faster the device will reduce the gain on the input link. A typical method of application of this device is to use a "first threshold value for monitoring the truncation distortion" and a "second preset threshold value" to be set to a "level value corresponding to the rated power value of the loudspeaker", thereby limiting the loudspeaker to its rated power or below most of the time and allowing the loudspeaker to operate over-rated power for a short period of time.

Based on a protection mechanism for real-time measurement of voltage and current values on a loudspeaker coil, a low-frequency component insensitive to human ears is superimposed on a sound source signal played by the loudspeaker in the prior art, so that the direct-current impedance of the loudspeaker is estimated in real time by measuring the voltage and the current on the loudspeaker coil, and then the temperature of the coil is estimated according to the linear corresponding relation between the temperature of the coil and the direct-current impedance of the coil, so that temperature protection is performed.

However, the above methods have drawbacks. Because the input signal of the loudspeaker can be converted into amplitude through the transformation of a model, the amplitude based on the input signal can not form effective amplitude protection at all; for temperature protection, except for ambient temperature, the temperature of the horn is mainly determined by the root mean square or mean square value of the input signal, and the temperature will rise to the extent of protection after the signal exceeds a threshold value for a period of time, so that the protection mechanism based on the signal amplitude tends to be over-protected; the method based on real-time measurement of the voltage and current values of the loudspeaker coil can achieve a good protection effect, but needs to introduce more extra software and hardware expenses beyond normal sound production of the loudspeaker.

Disclosure of Invention

Aiming at the problems in the prior art, the embodiment of the invention provides a loudspeaker protection device and a loudspeaker protection method.

In a first aspect, an embodiment of the present invention provides a speaker protection device, including: a temperature protection module;

the temperature protection module comprises a first detector, a first gain calculator and a first gain device;

the first detector is a root-mean-square detector or a mean-square detector, the input end of the first detector is used for receiving a first audio signal to be processed, and the output end of the first detector is connected with the input end of the first gain calculator;

the output end of the first gain calculator is connected with the input end of the first gain calculator;

the input end of the first booster is further used for receiving the first audio signal to be processed, and the output end of the first booster is used for outputting the processed first audio signal.

In a second aspect, an embodiment of the present invention provides a speaker protection method based on the speaker protection device in the first aspect, including:

acquiring a root mean square or a mean square value of a first audio signal to be processed in a first preset time window;

acquiring a first target gain value according to the root mean square or the mean square value and a corresponding threshold value determined by the rated power of the target loudspeaker;

and performing gain on the first audio signal to be processed according to the first target gain value and outputting the first audio signal to be processed.

According to the loudspeaker protection device and the loudspeaker protection method based on the loudspeaker protection device, the temperature protection module is constructed through the first detector, the gain calculator and the gain device, gain calculation is carried out according to the root mean square or mean square value of an input audio signal and a corresponding threshold value determined by the rated power of a target loudspeaker, a gain value required by temperature protection is obtained, and gain is carried out through the gain device, so that the temperature protection of the target loudspeaker is realized.

Drawings

In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, a brief description will be given below of the drawings required for the description of the embodiments or the prior art, and it is obvious that the drawings in the following description are some embodiments of the present invention, and it is obvious for those skilled in the art to obtain other drawings based on these drawings without creative efforts.

Fig. 1 is a schematic diagram of a first structure of a speaker protection device according to an embodiment of the present invention;

fig. 2 is a schematic diagram of a second structure of a speaker protection device according to an embodiment of the present invention;

fig. 3 is a schematic diagram of a third structure of a speaker protection device according to an embodiment of the present invention;

fig. 4 is a fourth structural diagram of a speaker protection device according to an embodiment of the present invention;

fig. 5 is a fifth structural diagram of a speaker protection device according to an embodiment of the present invention;

fig. 6 is a sixth structural schematic diagram of a speaker protection device according to an embodiment of the present invention;

fig. 7 is a seventh structural diagram of a speaker protection device according to an embodiment of the present invention;

fig. 8 is an eighth structural schematic diagram of a speaker protection device according to an embodiment of the present invention;

fig. 9 is a schematic diagram of a ninth structure of a speaker protection device according to an embodiment of the present invention;

fig. 10 is a schematic diagram of a tenth structure of a speaker protection device according to an embodiment of the present invention;

fig. 11 is an eleventh structural diagram of a speaker protection device according to an embodiment of the present invention;

fig. 12 is a twelfth structural schematic diagram of a speaker protection device according to an embodiment of the present invention;

fig. 13 is a first flowchart of a speaker protection method according to an embodiment of the invention;

fig. 14 is a second flowchart of a speaker protection method according to an embodiment of the invention;

fig. 15 is a schematic diagram of a third flow of a speaker protection method according to an embodiment of the present invention.

Description of the reference numerals

1. Upstream equipment, 2, a temperature protection module, 3, an amplitude protection module,

4. a target loudspeaker, 5, a signal protection module, 21, a first delayer,

22. a first gain device 23, a first detector 24, a first gain calculator,

31. a second delay, 32, a second gain, 33, an amplitude model,

34. a first peak detector, 35, a second gain calculator, 36, a second peak detector,

51. a third delay 52, a third gain 53, a third peak detector,

54. a third gain calculator.

Detailed Description

In order to make the objects, technical solutions and advantages of the embodiments of the present invention clearer, the technical solutions in the embodiments of the present invention will be clearly described below with reference to the drawings in the embodiments of the present invention, and it is obvious that the described embodiments are some embodiments, but not all embodiments, of the present invention. All other embodiments, which can be derived by a person skilled in the art from the embodiments given herein without making any creative effort, shall fall within the protection scope of the present invention.

Currently, in the field of amplitude protection, it is common knowledge in the electroacoustic industry to predict the amplitude of a linear model based on its input signal to a loudspeaker, and there are also established classical methods for determining the parameters of the linear model using a specific excitation signal. In order to deal with individual differences of loudspeakers of the same type and changes of amplitude models of the loudspeakers in the using process, in the prior art, a method for updating the loudspeaker models on line by monitoring voltage and current on loudspeaker coils without using specific excitation signals is provided.

For amplitude protection, experiments have shown that individual differences of the same model of horn introduce errors even smaller than the linear amplitude model itself, and thus the above-mentioned necessity for online updating of the model is questionable.

In view of the foregoing, embodiments of the present invention provide a speaker protection device and a speaker protection method based on the speaker protection device, so as to solve the problems in the prior art.

Fig. 1 is a schematic view of a first structure of a speaker protection device according to an embodiment of the present invention. An embodiment of the present invention provides a speaker protection device, including: a temperature protection module 2;

the temperature protection module 2 comprises a first detector 23, a first gain calculator 24 and a first gain 22;

the first detector 23 is a root-mean-square detector or a mean-square detector, an input end of the first detector is used for receiving a first audio signal to be processed, and an output end of the first detector is connected with an input end of the first gain calculator 24;

the output end of the first gain calculator 24 is connected with the input end of the first gain calculator 22;

the input end of the first booster 22 is further configured to receive the first audio signal to be processed, and the output end is configured to output the processed first audio signal.

Specifically, the first detector 23 may be a root mean square detector (RMS detector) or a mean square detector (MS detector); if the first detector 23 is a root mean square detector, the first detector is configured to obtain a root mean square of the first audio signal to be processed in a first preset time window; if the first detector 23 is a mean square value detector, it is configured to obtain a mean square value of the first audio signal to be processed within a first preset time window. In the embodiment of the present invention, the first detector 23 may obtain a root mean square or a mean square value of the first audio signal in a first preset time window, and output the root mean square or the mean square value to the first gain calculator 24.

The first gain calculator 24 is configured to obtain a first target gain value required by the target loudspeaker according to a corresponding threshold determined by the root mean square or the mean square value and a rated power of the target loudspeaker; it should be noted that the target speaker is a speaker that receives the audio signal output by the speaker protection device according to the embodiment of the present invention, and will not be described in detail hereinafter.

The first booster 22 is configured to boost and output the first audio signal to be processed according to the first target gain value.

It should be noted that the time length of the first preset time window may be selected according to actual needs, and this is not specifically limited in the embodiment of the present invention.

Referring to fig. 1, in the speaker protection apparatus according to the embodiment of the present invention, the temperature protection module 2 is used to implement temperature protection on the speaker. In a specific application environment, the temperature protection module 2 receives a first audio signal to be processed provided by any upstream device 1, and the first audio signal to be processed may be subjected to any other processing upstream. In the embodiment of the present invention, the first audio signal to be processed is duplicated into two identical audio signals, wherein one of the audio signals is directly input to the first booster 22, and the other of the audio signals is input to the first detector 23, passes through the first gain calculator 24, and is input to the first booster 22; the first gain calculator 22 has an input terminal for receiving a first audio signal to be processed, and another input terminal for receiving an output signal of the first gain calculator 24, wherein the output signal of the first gain calculator 24 is a first target gain value required for temperature protection. Thus, the first gain device 22 receives two input signals, one is the first audio signal to be processed, and the other is the first target gain value output by the first gain calculator 24, and the first gain device 22 gains the first audio signal to be processed according to the target gain value and outputs the first audio signal after the gain; if the output end of the first booster 22 is connected to the target speaker 4, the first audio signal after being gained is output to the target speaker 4.

It should be noted that, in all embodiments of the present invention, the upstream device 1 and the target loudspeaker 4 are external devices, which do not belong to the loudspeaker protection apparatus in the embodiments of the present invention, and will not be described again.

Specifically, the gain value calculated by the first gain calculator 24 may be set as the first target gain value, or a value obtained by smoothing the gain value calculated by the first gain calculator 24 may be set as the first target gain value. Specifically, the smoothing process for the gain value calculated by the first gain calculator 24 may be implemented by an envelope detector (envelope detector) with adjustable start time (attack time), recovery time (release time), and hold time (hold time).

Specifically, the first detector 23 has a variety of existing non-proprietary implementations in the digital and analog domains, for example:

one of them can be realized in an analog manner as a pseudo-root-mean-square detector (fake rms detector) consisting of a rectifying circuit and a filtering circuit.

And secondly, the square error detector can also be digitally implemented as a square operation plus a section of smoothing processing with adjustable smoothing window size.

In particular, the gain calculator has a variety of existing non-proprietary implementations available in the digital and analog domains.

It should be noted that, in the speaker protection apparatus according to the embodiment of the present invention, each component in the temperature protection module 2, such as the first detector 23, the first gain calculator 24, and the first gain calculator 22, may be implemented entirely in the digital domain, entirely in the analog domain, or partly in the digital domain and partly in the analog domain.

According to the loudspeaker protection device provided by the embodiment of the invention, the temperature protection module is constructed by the first detector, the gain calculator and the gain device, the gain calculation is carried out according to the root mean square or mean square value x of the input audio signal and the corresponding threshold value y determined by the rated power of the target loudspeaker, for example, min (y/x, the upper gain limit) is obtained, the gain value required by temperature protection is obtained, and the gain device is used for carrying out gain, so that the temperature protection of the target loudspeaker is realized.

Fig. 2 is a schematic diagram of a second structure of a speaker protection device according to an embodiment of the present invention. Based on the above embodiment, the temperature protection module 2 further includes a first delayer 21;

the input end of the first delayer 21 is used for receiving the first audio signal to be processed, and the output end is connected to the input end of the first gainer 22.

Specifically, the first delayer 21 is configured to delay a first audio signal to be processed for a first preset time and output the delayed first audio signal to the first gainer 22.

Referring to fig. 2, after the first audio signal to be processed is copied into two identical audio signals, one of the audio signals is input into the first delayer 21, delayed and input into the first gainer 22, and the other of the audio signals is input into the first detector 23, passed through the first gain calculator 24, and input into the first gainer 22.

The specific preset time may be determined according to the needs of practical applications, and the embodiment of the present invention is not limited in this respect.

The embodiment of the invention delays the audio signal to be processed, and can ensure that the final output power is in a required range by reducing the gain in advance under the application scene that the power needs to be strictly controlled.

Fig. 3 is a schematic diagram of a third structure of a speaker protection device according to an embodiment of the present invention. Based on the above embodiment, the apparatus further comprises one or more sequentially connected amplitude protection modules 3; the input end of the amplitude protection module 3 is connected with the temperature protection module 2 or the amplitude protection module 3 connected in front, and the output end of the amplitude protection module 3 is connected with the amplitude protection module 3 connected in back or outputs a processed audio signal;

the amplitude protection module 3 comprises a second booster 32, an amplitude model 33 and a second gain calculator 35;

the input end of the amplitude model 33 is used for receiving a second audio signal to be processed, and the output end is connected to the input end of the second gain calculator 35; the second audio signal to be processed is an audio signal output by the temperature protection module 2, specifically, an audio signal processed by the first booster 22, or an audio signal output by the amplitude protection module 3 connected in front;

the output end of the second gain calculator 35 is connected with the input end of the second gain calculator 32;

the input end of the second booster 32 is further configured to receive the second audio signal to be processed, and the output end is connected to the amplitude protection module 3 connected in the rear or outputs the processed second audio signal.

Specifically, the amplitude model 33 is configured to obtain an expected loudspeaker amplitude of the second audio signal to be processed, and output the expected loudspeaker amplitude to the second gain calculator 35;

the second gain calculator 35 is configured to obtain a second target gain value according to the instantaneous value of the expected horn amplitude and the rated maximum amplitude of the target horn;

specifically, the gain value calculated by the second gain calculator 35 may be set as the second target gain value, or a value obtained by smoothing the gain value calculated by the second gain calculator 35 may be set as the second target gain value. Specifically, the smoothing process for the gain value calculated by the second gain calculator 35 may be implemented by an envelope detector (envelope detector) whose start time (attack time), recovery time (release time), and hold time (hold time) are respectively adjustable.

The second booster 32 is configured to boost and output the second audio signal to be processed according to the second target gain value.

Referring to fig. 3, the speaker protection apparatus shown in fig. 3 includes a temperature protection module 2 and an amplitude protection module 3, and an output signal of the temperature protection module 2 is input to the amplitude protection module 3 for amplitude protection. Specifically, the temperature protection module 2 outputs two identical audio signals (without the first delayer 21), or the temperature protection module 2 outputs two audio signals with time difference (with the first delayer 21), and the second audio signal to be processed received by the amplitude protection module 3 is the two audio signals with time difference or without time difference output by the temperature protection module 2. The output signal of the amplitude protection module 3 is an audio signal finally output to the target loudspeaker, and if the output end of the amplitude protection module 3 is connected with the target loudspeaker 4, the second audio signal after the gain is output to the target loudspeaker 4.

Fig. 4 is a schematic diagram of a fourth structure of a speaker protection device according to an embodiment of the present invention, where the speaker protection device shown in fig. 4 includes a temperature protection module 2 and two amplitude protection modules 3, the temperature protection module 2 receives a first audio signal to be processed provided by an upstream device 1, and outputs the first audio signal to the amplitude protection module 3 (referred to as a first amplitude protection module) connected thereto after temperature protection processing, and at this time, the processed first audio signal output by the temperature protection module 2 serves as a second audio signal to be processed. The first amplitude protection module performs amplitude protection processing on the second audio signal to be processed, and then outputs the second audio signal to an amplitude protection module 3 (referred to as a second amplitude protection module) connected behind the first audio signal, where the processed second audio signal output by the first amplitude protection module is used as the second audio signal to be processed by the second amplitude protection module. If the amplitude protection module 3 is connected behind the second amplitude protection module, the process is repeated, the output of the former amplitude protection module is used as the input of the latter amplitude protection module, and the output of the last amplitude protection module is used as the final output signal. If the output end of the last amplitude protection module is connected with the target loudspeaker 4, the second audio signal after the gain, namely the audio signal output by the last amplitude protection module, is output to the target loudspeaker 4.

In this embodiment, fig. 3 shows a speaker protection device including one temperature protection module 2 and one amplitude protection module 3, fig. 4 shows a speaker protection device including one temperature protection module 2 and two amplitude protection modules 3, and further, the speaker protection device may further include more amplitude protection modules that are sequentially connected to implement amplitude protection, which is not described herein again.

The above-described series connection of multiple amplitude protection modules can be used to set multiple amplitude thresholds and different time constants for different amplitude thresholds.

Specifically, the amplitude model has a variety of existing non-proprietary implementations available in the digital and analog domains, for example:

one of the two modes can be realized in an analog mode as a second-order low-pass analog filter with adjustable cut-off frequency and q value or an amplitude model with a plurality of analog filters in cascade connection.

And secondly, the two-stage low-pass filter can also be implemented digitally as a second-order low-pass digital filter with adjustable cut-off frequency and q value or an amplitude model formed by cascading a plurality of digital filters.

It should be noted that the amplitude model in the embodiment of the present invention is an amplitude model that is debugged in advance according to limited parameters of the same-type horn, and predicts the amplitude of the same-type horn through the amplitude model that is built in advance, and reduces the gain on the signal chain in advance when the super-amplitude is predicted; the amplitude model does not need to be updated on line, so that the voltage and the current on the horn coil do not need to be measured in real time, the pressure caused by real-time measurement and frequent online updating is avoided, and resources are saved.

According to the embodiment of the invention, the temperature protection and the amplitude protection of the loudspeaker are realized through the temperature protection module and the amplitude protection module together.

Fig. 5 is a schematic diagram of a fifth structure of a speaker protection device according to an embodiment of the present invention, in which based on the above embodiment, the amplitude protection module further includes a second delayer;

the input end of the second delayer is used for receiving a second audio signal to be processed, and the output end of the second delayer is connected with the second booster.

Specifically, the second delayer 31 is configured to delay a second audio signal to be processed for a second preset time, and output the second audio signal to the second gainer 32.

Referring to fig. 5, the second audio signal to be processed includes two paths of audio signals with or without time difference, wherein one path of audio signal is input to the second delayer 31, and then input to the second gainer 32 after being delayed, and the other path of audio signal is input to the amplitude model 33, passes through the second gain calculator 35, and then input to the second gainer 32.

Similarly, this embodiment is applicable to the case where a plurality of amplitude protection modules are connected in series as shown in fig. 4, and all or part of the amplitude protection modules may be added with a delay device, and may be flexibly combined as required. All adjustments to the amplitude protection modules in the subsequent embodiments are all applicable to the case where a plurality of amplitude protection modules are connected in series, and all adjustments may be implemented in all amplitude protection modules connected in series or in some amplitude protection modules connected in series, and are not described in detail hereinafter.

Fig. 6 is a sixth structural schematic diagram of a speaker protection device according to an embodiment of the present invention, and based on the above embodiment, the input end of the second gain calculator 35 is further configured to receive a second audio signal to be processed.

Referring to fig. 6, the second gain calculator 35 in this embodiment has two input signals, one is the second audio signal to be processed, and the other is the expected loudspeaker amplitude output by the amplitude model 33.

In this embodiment, the second gain calculator 35 performs two comparisons, first, compares the instantaneous value of the expected horn amplitude output by the amplitude model 33 with the target horn rated maximum amplitude to obtain a gain value a; secondly, comparing the instantaneous value of the second audio signal to be processed with the rated maximum voltage of the current signal link to obtain a gain value b; further, the smaller of the gain value a and the gain value b is taken as a second target gain value.

Specifically, the smaller of the gain value a and the gain value b may be set as the second target gain value, or the smaller of the gain value a and the gain value b may be smoothed to be set as the second target gain value. Specifically, the smoothing process for the smaller value may be implemented by an envelope detector (envelope detector) with adjustable start time (attack time), recovery time (release time), and hold time (hold time).

This embodiment is applicable to the case where a plurality of amplitude protection modules of fig. 4 are connected in series. In this embodiment, the amplitude protection module realizes amplitude protection and signal protection for the speaker through two paths of input signals.

Fig. 7 is a seventh structural schematic diagram of a speaker protection apparatus according to an embodiment of the present invention, and based on the above embodiment, the amplitude protection module further includes a first peak detector 34;

the input of the first peak detector 34 is connected to the output of the amplitude model, and the output is connected to the input of the second gain calculator 35.

Specifically, the first peak detector 34 is configured to detect a peak value of the expected horn amplitude, and output the peak value of the expected horn amplitude to the second gain calculator 35;

in the foregoing embodiment, when the peak detector is not added to the amplitude protection module, the second gain calculator performs the gain calculation according to the instantaneous value of the expected horn amplitude output by the amplitude protection module and/or the instantaneous value of the second audio signal to be processed. In this embodiment, the expected horn amplitude output by the amplitude protection module is detected by the first peak detector to obtain a peak value, and the second gain calculator performs gain calculation according to the peak value of the expected horn amplitude output by the amplitude protection module.

In particular, peak detectors have a number of existing non-proprietary implementations in the digital and analog domains to choose from, for example: the peak detector can be realized in an analog mode as an analog peak detection circuit, and can also be realized in a digital mode as a digital peak detector which is basically equivalent to the analog peak detection circuit.

Fig. 8 is an eighth structural schematic diagram of a loudspeaker protection apparatus according to an embodiment of the present invention, and based on the above embodiment, the amplitude protection module further includes a second peak detector 36;

the second peak detector 36 has an input for receiving a second audio signal to be processed and an output connected to the input of the second gain calculator 35.

Specifically, the second peak detector in this embodiment is configured to detect a peak value of the second audio signal to be processed, and output the peak value of the second audio signal to be processed to the second gain calculator 35.

Referring to fig. 8, the second gain calculator 35 in the present embodiment has two input signals, which are the peak value of the second audio signal to be processed and the peak value of the expected horn amplitude output by the amplitude model 33, and still performs two comparisons, i.e., comparing the instantaneous values in the previous embodiment and comparing the peak values in the present embodiment. Specifically, firstly, comparing the peak value of the expected horn amplitude output by the amplitude model 33 with the target horn rated maximum amplitude to obtain a gain value c; secondly, comparing the peak value of the second audio signal to be processed with the rated maximum voltage of the current signal link to obtain a gain value d; further, the smaller of the gain value c and the gain value d is set as a second target gain value.

Specifically, the smaller of the gain value c and the gain value d may be set as the second target gain value, or the smaller of the gain value c and the gain value d may be smoothed to be set as the second target gain value. Specifically, the smoothing process for the smaller value may be implemented by an envelope detector (envelope detector) with adjustable start time (attack time), recovery time (release time), and hold time (hold time).

In this embodiment, the amplitude protection module realizes amplitude protection and signal protection for the speaker through two paths of input signals.

Fig. 9 is a schematic diagram of a ninth structure of a speaker protection device according to an embodiment of the present invention. In addition to the above-mentioned risks in terms of amplitude and temperature, if the amplitude of the signal output to the horn exceeds the maximum output capability of the actual output device, truncated distortion is introduced into the output signal, which, although not necessarily directly damaging the horn, may cause audible degradation, and thus is also to be avoided. Based on the above embodiments, in order to solve the problem of truncation distortion, the apparatus according to the embodiments of the present invention further includes one or more signal protection modules 5 connected in sequence; the input end of the signal protection module 5 is connected with the temperature protection module 2 or the signal protection module 5 connected in front, and the output end of the signal protection module 5 is connected with the signal protection module 5 connected in back or outputs a processed audio signal;

the signal protection module 5 includes a third gain calculator 52 and a third gain calculator 54;

the input end of the third gain calculator 54 is configured to receive a third audio signal to be processed, and the output end thereof is connected to the input end of the third booster 52; the third audio signal to be processed is an audio signal output by the temperature protection module 2 or an audio signal output by a signal protection module connected in front;

the input end of the third booster 52 is further configured to receive a third audio signal to be processed, and the output end is connected to the signal protection module 5 connected behind or outputs the processed third audio signal.

The third gain calculator 54 is configured to compare an instantaneous value of the second audio signal to be processed with a rated maximum voltage of the current signal link, and obtain a third target gain value;

specifically, the gain value calculated by the third gain calculator 54 may be set as the third target gain value, or a value obtained by smoothing the gain value calculated by the third gain calculator 54 may be set as the third target gain value. Specifically, the smoothing process for the gain value calculated by the third gain calculator 54 may be implemented by an envelope detector (envelope detector) with adjustable start time (attack time), recovery time (release time), and hold time (hold time).

The third gaining device 52 is configured to gain and output a third audio signal to be processed according to the third target gain value.

Referring to fig. 9, the speaker protection apparatus shown in fig. 9 includes a temperature protection module 2 and a signal protection module 5, and an output signal of the temperature protection module 2 is input to the signal protection module 5 for signal protection. Specifically, the temperature protection module 2 outputs two identical audio signals (without the first delay 21), or the temperature protection module 2 outputs two audio signals with time difference (with the first delay 21), and then the third audio signal to be processed received by the signal protection module 5 is the two audio signals with time difference or without time difference output by the temperature protection module 2. The output signal of the signal protection module 5 is an audio signal finally output to the target loudspeaker, and if the output end of the signal protection module 5 is connected with the target loudspeaker 4, the third audio signal after the gain is output to the target loudspeaker 4.

Fig. 10 is a schematic diagram of a tenth structure of a speaker protection device according to an embodiment of the present invention, where the speaker protection device shown in fig. 10 includes a temperature protection module 2 and two signal protection modules 3, the temperature protection module 2 receives a first audio signal to be processed provided by an upstream device 1, and outputs the first audio signal to the signal protection module 3 (referred to as a first signal protection module) connected thereto after temperature protection processing, and at this time, the processed first audio signal output by the temperature protection module 2 serves as a third audio signal to be processed. The first signal protection module performs signal protection processing on the third audio signal to be processed, and then outputs the third audio signal to a signal protection module 5 (called as a second signal protection module) connected behind the first signal protection module, and at this time, the processed third audio signal output by the first signal protection module is used as the third audio signal to be processed by the second signal protection module. If the rear of the second signal protection module is also connected with a signal protection module 5, and so on, the output of the former signal protection module is used as the input of the latter signal protection module, and the output of the last signal protection module is used as the final output signal. If the output end of the last signal protection module is connected with the target loudspeaker 4, the third audio signal after the gain, namely the audio signal output by the last signal protection module, is output to the target loudspeaker 4.

In this embodiment, fig. 9 shows a speaker protection device including one temperature protection module 2 and one signal protection module 5, fig. 10 shows a speaker protection device including one temperature protection module 2 and two signal protection modules 5, and further, signal protection may be implemented by sequentially connecting more signal protection modules, which is not described herein again.

The above-mentioned serial connection of multiple signal protection modules can be used to set multiple signal thresholds and set different time constants for different signal thresholds.

According to the embodiment of the invention, the temperature protection and the signal protection of the loudspeaker are realized through the temperature protection module and the signal protection module together.

Fig. 11 is a schematic diagram of an eleventh structure of a speaker protection device according to an embodiment of the present invention, and based on the foregoing embodiment, the signal protection module 5 further includes the third peak detector 53;

the input of the third peak detector 53 is configured to receive a third audio signal to be processed, and the output thereof is connected to the input of the third gain calculator 54.

Specifically, the third peak detector 53 is configured to detect a peak value of the second audio signal to be processed, and output the detected peak value to the third gain calculator 52.

In the case where the peak detector is not added to the signal protection module of the previous embodiment, the third gain calculator 54 compares the instantaneous value of the second audio signal to be processed with the rated maximum voltage of the current signal link to perform a gain calculation. In this embodiment, the third gain calculator 54 is configured to compare a peak value of the second audio signal to be processed with a rated maximum voltage of the current signal link, and obtain a third target gain value.

In particular, peak detectors have a number of existing non-proprietary implementations in the digital and analog domains to choose from, for example: an analog peak detection circuit may be implemented in an analog manner or may be implemented in a digital manner as a digital peak detector substantially equivalent to the analog peak detection circuit described above.

The embodiment is suitable for the case that a plurality of signal protection modules are connected in series in fig. 10, and the peak detectors may be added to all or part of the signal protection modules, and may be flexibly combined as required.

Fig. 12 is a schematic diagram of a twelfth structure of a speaker protection device according to an embodiment of the present invention, based on the above embodiment, the signal protection module 5 further includes a third delayer 51;

the input end of the third delay 51 is used for receiving a third audio signal to be processed, and the output end is connected to the third booster 52.

Specifically, the third delayer 51 is configured to delay a third audio signal to be processed for a third preset time, and output the third audio signal to the third gainer 52.

Referring to fig. 12, the third audio signal to be processed includes two paths of audio signals with or without time difference, wherein one path of audio signal is input to a third delayer 51, and is input to a third multiplier 52 after being delayed, and the other path of audio signal is input to a third peak detector 53, and is input to the third multiplier 52 after passing through a third gain calculator 54.

Similarly, this embodiment is applicable to the case where a plurality of signal protection modules in fig. 10 are connected in series, and all or part of the signal protection modules may be added with a delay device, and may be flexibly combined as required.

In summary, the speaker protection device according to the embodiments of the present invention has a simple structure, and can be implemented by flexible and various software and hardware, and each component of each speaker protection device embodiment can be implemented entirely in a digital domain, entirely in an analog domain, or partly in the digital domain and partly in the analog domain, so that low software and hardware overhead can be provided, and speaker temperature, amplitude and signal protection can be effectively implemented.

It should be noted that, with the speaker protection device according to the embodiment of the present invention, if the processed audio signal leaves the speaker protection device and is further processed by other linear processing before entering the speaker, for example, filtered by a high-pass filter, the following two changes may be made so that the control given by the gain calculator in each protection module conforms to the final actual requirement:

1. the same linear processing as described above, for example a high pass filter, is added to the chain on which the gain calculator of the temperature protection module is located.

2. And respectively introducing signals before and after the linear processing on a link where a gain calculator of the temperature protection module is positioned into a subsequent module, performing temperature and amplitude protection according to the signals after the linear processing, and performing signal protection according to the signals before and/or after the linear processing.

Fig. 13 is a schematic view of a first flow of a speaker protection method according to an embodiment of the present invention, and based on the speaker protection apparatus according to the foregoing embodiment, an embodiment of the present invention further provides a speaker protection method, including:

130, obtaining a root mean square or a mean square value of a first audio signal to be processed in a first preset time window;

131, obtaining a first target gain value according to the root mean square or the mean square value and a corresponding threshold value determined by the rated power of the target loudspeaker;

and 132, performing gain on the first audio signal to be processed according to the first target gain value, and then outputting the first audio signal to be processed.

It should be noted that the method described in this embodiment may be implemented by the first structure of the speaker protection apparatus shown in fig. 1, that is, by the temperature protection module, and the

specific steps

130, 131, and 132 are executed by the temperature protection module.

A first audio signal to be processed output from the upstream device 1 is input to the speaker protection apparatus shown in fig. 1 in two paths, wherein one path of signal is directly input to the booster and is a signal for gain output, the link is a main link, and the other path of signal is input to the booster after being processed by the first detector and the gain calculator, and the link is called a bypass or a control link. In all embodiments of the present invention, a link for performing gain output on a signal is referred to as a main link, and a link for processing a signal to implement gain control is referred to as a control link, which will not be described in detail later.

In step 130, a root mean square or a mean square value of a first audio signal to be processed in a first preset time window is obtained through a first detector; the length of the first preset time window may be adjusted according to the actual application requirement, which is not limited in the embodiment of the present invention. For example, in some applications, the length of the first preset time window may range between 10ms and 1 s.

In step 131, the gain calculator compares the root mean square or the mean square value obtained by the first detector with a corresponding threshold determined by the rated power of the target loudspeaker to obtain a first target gain value at which the average output power of the audio signal in the first preset time window does not exceed the rated power of the target loudspeaker, and outputs the first target gain value to the booster for gain.

In step 132, the gain calculator gains the audio signal input by the main link according to the first target gain value obtained by the gain calculator. Specifically, the audio signal input by the main link is multiplied by the first target gain value and then output.

The gain of the embodiment of the invention is as follows: the target gain value is used for controlling the amplification or attenuation of the signal, the purpose of controlling the average output power of the signal, the amplitude of the loudspeaker caused by the average output power of the signal and the strength of the signal is to control the temperature protection, the amplitude protection, the signal protection and the like of the loudspeaker, and the details are not repeated hereafter.

According to the embodiment of the invention, the root mean square or mean square value of the audio signal to be processed in a certain time window is monitored in real time through the first detector, and the gain on a signal chain is reduced before, when or after the root mean square or mean square value exceeds a threshold value determined by the rated power of a target loudspeaker, the temperature of a loudspeaker coil does not need to be actually estimated, so that the temperature protection of the loudspeaker can be realized without measuring the voltage and the current on the loudspeaker coil in real time.

Based on the foregoing embodiment, in step 132, the outputting the to-be-processed first audio signal after performing gain on the to-be-processed first audio signal according to the second target gain value further includes:

and smoothing the first target gain value, and taking the smoothed result as the first target gain value.

For the gain values calculated by all the gain calculators in all the embodiments of the present invention, the calculated gain value can be directly used as the target gain value, or the gain value obtained after smoothing can be used as the target gain value. Specifically, all smoothing processes may be implemented by an envelope detector (envelope detector) with adjustable start time (attack time), recovery time (release time), and hold time (hold time), which will not be described herein again.

In this embodiment, a value obtained by smoothing the calculated gain value is used as the target gain value.

According to the embodiment of the invention, gain calculation is carried out according to the root mean square or mean square value of the input audio signal and the corresponding threshold value determined by the rated power of the target loudspeaker, the gain value required by temperature protection is obtained, and gain is carried out through the gain device, so that the temperature protection of the target loudspeaker is realized. According to the embodiment of the invention, the root mean square or mean square value of the audio signal to be processed in a certain time window is monitored in real time by the first detector, the gain on a signal chain is reduced before, during or after the root mean square or mean square value exceeds a corresponding threshold value determined by the rated power of a target loudspeaker according to actual application requirements, the temperature of a loudspeaker coil does not need to be actually estimated, and therefore, the temperature protection of the loudspeaker can be realized without measuring the voltage and the current on the loudspeaker coil in real time.

Based on the foregoing embodiment, in step 132, the performing gain on the to-be-processed first audio signal according to the first target gain value and outputting the to-be-processed first audio signal includes:

delaying the first audio signal to be processed for a first preset time;

and the delayed first audio signal to be processed is output after being gained according to the first target gain value.

It should be noted that the method described in this embodiment may be implemented by the second structure of the speaker protection apparatus shown in fig. 2.

In the foregoing embodiment, the input audio signal is directly subjected to gain without delay; in the embodiment, the audio signal which needs to be gained is delayed for a certain time and then gained. The difference between delayed and non-delayed gain is that in the delayed case the gain will start to drop before the expected power exceeds the threshold. Preferably, the first preset time ranges from 1ms to 15 ms.

Fig. 14 is a schematic diagram of a second process of a speaker protection method according to an embodiment of the present invention, based on the above embodiment, the speaker protection method further includes:

140 obtaining an expected loudspeaker amplitude of the second audio signal to be processed; the second audio signal to be processed is an audio signal obtained by performing gain on the first audio signal to be processed, or an audio signal obtained by performing gain on the second audio signal to be processed;

141, obtaining a second target gain value according to the expected horn amplitude and the rated maximum amplitude of the target horn;

and 142, performing gain on the second audio signal to be processed according to the second target gain value, and then outputting the second audio signal to be processed.

It should be noted that the method described in this embodiment may be implemented by the third structure of the speaker protection device shown in fig. 3 or the fourth structure of the speaker protection device shown in fig. 4, that is, the method is implemented by adding the amplitude protection module on the basis of the temperature protection module. The

specific steps

140, 141 and 142 are performed by the amplitude protection module.

If the method is implemented by the structure of fig. 3, the second audio signal to be processed is the audio signal obtained by performing the gain on the first audio signal to be processed, that is, the output signal of the temperature protection module. If the method is implemented by the structure of fig. 4, that is, a plurality of amplitude protection modules are connected in series behind the temperature protection module, the to-be-processed second audio signal of the first amplitude protection module is the audio signal obtained by performing gain on the to-be-processed first audio signal, that is, the output signal of the temperature protection module, and the to-be-processed second audio signal of the subsequent amplitude protection module is the output signal of the preceding amplitude protection module.

Step 140 obtains the expected horn amplitude of the second audio signal to be processed through the amplitude model, and outputs the expected horn amplitude to the gain calculator for processing. As described above, the amplitude model of the embodiment of the present invention is an amplitude model that is debugged in advance according to the limited parameters of the same-type horn, and predicts the amplitude of the same-type horn through the amplitude model that is built in advance, and reduces the gain on the signal chain in advance when the super-amplitude is predicted; the amplitude model does not need to be updated on line, so that the voltage and the current on the horn coil do not need to be measured in real time, software and hardware expenses caused by real-time measurement and frequent online updating are avoided, and resources are saved.

In step 141, the gain calculator obtains a second target gain value that the amplitude of the horn does not exceed the maximum acceptable amplitude of the target horn according to the comparison between the expected amplitude of the horn and the maximum amplitude of the target horn. It should be noted that, here, since there is no peak detector, the gain calculator obtains the instantaneous value of the expected horn amplitude, and therefore, the instantaneous value of the expected horn amplitude is compared with the rated maximum amplitude of the target horn.

And 142, the booster performs gain on the second audio signal to be processed according to the second target gain value and outputs the second audio signal, specifically, the audio signal input by the main link is multiplied by the second target gain value and then output.

The dual protection of temperature and amplitude is realized through the temperature protection module and the amplitude protection module in the embodiment.

Based on the above embodiment, in step 142, the step of performing gain output on the second audio signal to be processed according to the second target gain value further includes:

and smoothing the second target gain value, and taking the smoothed result as the second target gain value.

Based on the foregoing embodiment, in step 142, the performing gain on the second audio signal to be processed according to the second target gain value and outputting the second audio signal to be processed specifically includes:

delaying the second audio signal to be processed for a second preset time;

and according to the second target gain value, the delayed second audio signal to be processed is output after being gained.

It should be noted that the method described in this embodiment may be implemented by the fifth structure of the speaker protection device shown in fig. 5 or the fourth structure of the speaker protection device shown in fig. 4.

In the foregoing embodiment, the amplitude protection module directly gains the input audio signal without delay; in the embodiment, the audio signal which needs to be gained is delayed for a certain time and then gained. The difference between delayed and non-delayed gains is that in the delayed case the gain will start to drop before the expected amplitude exceeds the protection threshold to further ensure the protection effect. Preferably, the second preset time ranges from 1ms to 15 ms.

Similarly, in this embodiment, a plurality of amplitude protection modules shown in fig. 4 may be connected in series and then executed, and all or part of the amplitude protection modules may be added with a delay device, and may be flexibly combined as required.

Based on the above embodiment, in step 141, obtaining a second target gain value according to the expected horn amplitude and the rated maximum amplitude of the target horn includes:

141.11, obtaining a gain value a according to the instantaneous value of the expected horn amplitude and the rated maximum amplitude of the target horn; acquiring a gain value b according to the instantaneous value of the second audio signal to be processed and the rated maximum voltage of the current signal link;

141.12, the smaller of the gain value a and the gain value b is used as a second target gain value.

It should be noted that the method described in this embodiment may be implemented by the sixth structure of the speaker protection device shown in fig. 6 or the fourth structure of the speaker protection device shown in fig. 4.

Referring to fig. 6, in the amplitude protection module of the speaker protection apparatus in fig. 6, the gain calculator has two input signals, one is an instantaneous value of the second audio signal to be processed, and the other is an instantaneous value of the expected loudspeaker amplitude. The gain calculator obtains a gain value a by comparing the instantaneous value of the amplitude of the expected loudspeaker with the rated maximum amplitude of the target loudspeaker, and carries out amplitude protection; obtaining a gain value b by comparing the instantaneous value of the second audio signal to be processed with the rated maximum voltage of the current signal link, and performing signal protection; further, the smaller of the gain value a and the gain value b is taken as a second target gain value.

Similarly, in this embodiment, a plurality of amplitude protection modules shown in fig. 4 may be connected in series and then executed, and each amplitude protection module may implement signal protection entirely or partially, and may be flexibly combined as required.

The embodiment realizes signal protection through the amplitude protection module, thereby realizing temperature protection, amplitude protection and signal protection on the whole.

Based on the above embodiment, the obtaining a second target gain value according to the expected horn amplitude and the rated maximum amplitude of the target horn in step 141 specifically includes:

141.21, obtaining a second target gain value according to the peak value of the expected horn amplitude and the rated maximum amplitude of the target horn.

It should be noted that the method described in this embodiment may be implemented by the seventh structure of the speaker protection device shown in fig. 7 or the fourth structure of the speaker protection device shown in fig. 4.

Referring to fig. 7, since the peak detector is connected to the amplitude model, the input signal of the gain calculator is the peak value of the expected horn amplitude, and the gain calculator compares the peak value of the expected horn amplitude with the rated maximum amplitude of the target horn to obtain a second target gain value.

Similarly, in this embodiment, a plurality of amplitude protection modules shown in fig. 4 may be connected in series and then executed, and all or part of the amplitude protection modules may be added with the peak detector, and may be flexibly combined as required.

Based on the above embodiment, in step 141, the obtaining a second target gain value according to the peak value of the expected horn amplitude and the rated maximum amplitude of the target horn specifically includes:

141.31, detecting a peak value of the expected horn amplitude and a peak value of the second audio signal to be processed;

141.32, obtaining a gain value c according to the peak value of the expected horn amplitude and the rated maximum amplitude of the target horn; obtaining a gain value d according to the peak value of the second audio signal to be processed and the rated maximum voltage of the current signal link;

141.33, the smaller of the gain value c and the gain value d is used as a second target gain value.

It should be noted that the method described in this embodiment may be implemented by the eighth structure of the speaker protection device shown in fig. 8 or the fourth structure of the speaker protection device shown in fig. 4.

Referring to fig. 8, since the peak detector is added before the second audio signal to be processed enters the gain calculator, the expected horn amplitude obtained by the amplitude model also passes through the peak detector, and thus the two signals obtained by the gain calculator are the peak value of the second audio signal to be processed and the peak value of the expected horn amplitude, respectively.

The embodiment first detects the peak value of the second audio signal to be processed and the peak value of the expected loudspeaker amplitude through two peak value detectors, and the two peak values enter the gain calculator. The gain calculator compares the peak value of the expected loudspeaker amplitude with the rated maximum amplitude of the target loudspeaker to obtain a gain value c; and comparing the peak value of the second audio signal to be processed with the rated maximum voltage of the current signal link to obtain a gain value d. Specifically, the gain value c and the gain value d obtained by comparing and calculating are the same as the gain value a and the gain value b calculated in the foregoing embodiment, and are not described here again, but the peak value calculation is performed here, and the foregoing embodiment calculates through an instantaneous value; the method for calculating the second target gain value by the gain calculator through the gain value c and the gain value d is the same as the foregoing embodiment, and is not described herein again.

Fig. 15 is a schematic view of a third flow of a speaker protection method according to an embodiment of the present invention, based on the above embodiment, the speaker protection method further includes:

150, obtaining a third target gain value according to the instantaneous value or the peak value of the third audio signal to be processed and the rated maximum voltage of the current signal link; the third audio signal to be processed is an audio signal obtained by performing gain on the first audio signal to be processed, or an audio signal obtained by performing gain on the third audio signal to be processed;

and 151, performing gain on the third audio signal to be processed according to the third target gain value, and then outputting the third audio signal to be processed.

It should be noted that the method described in this embodiment may be implemented by the ninth structure of the speaker protection device shown in fig. 9, or the method described in this embodiment may be implemented by the eleventh structure of the speaker protection device shown in fig. 11, or the tenth structure of the speaker protection device shown in fig. 10, that is, the method is implemented by adding the signal protection module on the basis of the temperature protection module. The

specific steps

150 and 151 are performed by the signal protection module.

If the processing is performed according to the instantaneous value of the third audio signal to be processed, that is, step 150, a third target gain value is obtained according to the instantaneous value of the third audio signal to be processed and the rated maximum voltage of the current signal link, the method is implemented by the structure of fig. 9, where the third audio signal to be processed is an audio signal obtained by performing gain on the first audio signal to be processed, that is, an output signal of the temperature protection module. If the method is implemented by the structure of fig. 10, that is, a plurality of signal protection modules are connected in series behind the temperature protection module, the third audio signal to be processed of the first signal protection module is the audio signal obtained by performing the gain on the first audio signal to be processed, that is, the output signal of the temperature protection module, and the third audio signal to be processed of the subsequent signal protection module is the output signal of the previous signal protection module. In this embodiment, an instantaneous value of the third audio signal to be processed is obtained, a rated maximum voltage of the current signal link is obtained, the instantaneous value of the third audio signal to be processed and the rated maximum voltage of the current signal link are compared by the gain calculator, a third target gain value which enables the current signal link to output an output without clipping is obtained, and the third target gain value is output to the gain unit. The gain unit gains the third audio signal to be processed according to the third target gain value, and specifically, multiplies the audio signal input by the main link by the third target gain value and outputs the result.

If the third target gain value is obtained according to the peak value of the third audio signal to be processed, that is, step 150, according to the peak value of the third audio signal to be processed and the rated maximum voltage of the current signal link, the method is implemented by the structure of fig. 11, and the audio signal obtained by performing the gain on the first audio signal to be processed, that is, the output signal of the temperature protection module, is the third audio signal to be processed. If the method is implemented by the structure of fig. 10, that is, a plurality of signal protection modules are connected in series behind the temperature protection module, the third audio signal to be processed of the first signal protection module is the audio signal obtained by performing the gain on the first audio signal to be processed, that is, the output signal of the temperature protection module, and the third audio signal to be processed of the subsequent signal protection module is the output signal of the previous signal protection module. In this embodiment, the peak value of the third audio signal to be processed is detected by the peak value detector, the rated maximum voltage of the current signal link is obtained, the peak value of the third audio signal to be processed and the rated maximum voltage of the current signal link are compared by the gain calculator, a third target gain value which enables the current signal link to output a top-clipping-free signal is obtained, and the third target gain value is output to the gain unit. The gain unit gains the third audio signal to be processed according to the third target gain value, and specifically, multiplies the audio signal input by the main link by the third target gain value and outputs the result.

The dual protection of temperature and signal is realized through temperature protection module and signal protection module to this embodiment.

Based on the above embodiment, in step 151, the step of performing gain on the third audio signal to be processed according to the third target gain value and then outputting the third audio signal to be processed further includes:

and smoothing the third target gain value, and taking the smoothed result as the third target gain value.

In this embodiment, a value obtained by smoothing the gain value obtained by calculation is used as the target gain value.

Based on the foregoing embodiment, in step 151, the step of performing gain on the third audio signal to be processed according to the third target gain value and outputting the third audio signal to be processed includes:

delaying the third audio signal to be processed for a third preset time;

and according to the third target gain value, the delayed third audio signal to be processed is output after being gained.

It should be noted that the method described in this embodiment may be implemented by the eleventh structure of the speaker protection device shown in fig. 11 or the tenth structure of the speaker protection device shown in fig. 10.

In the foregoing embodiment, the signal protection module directly gains the input audio signal without delay; in the embodiment, the audio signal which needs to be gained is delayed for a certain time and then gained. The difference between delayed and non-delayed gain is that in the delayed case the gain will start to drop before the expected output signal exceeds the protection threshold to further ensure the protection effect. Preferably, the third preset time ranges from 1ms to 15 ms.

It should be noted that, in the speaker protection methods provided in all embodiments of the present invention, if the processed final output audio signal is further subjected to other linear processing before entering the speaker, for example, filtering through a high pass filter, etc., a linear processing identical to the linear processing may be added to the link where the gain calculator of the temperature protection module is located, for example, a high pass filter is added, signals before and after the linear processing on the link where the gain calculator of the temperature protection module is located are respectively introduced into subsequent modules, temperature and amplitude protection is performed according to the signal after the linear processing, and signal protection is performed according to the signal before and/or after the linear processing, so that the gain control is in accordance with the final actual requirement, and the actual requirement is met.

In summary, embodiments of the present invention provide a speaker protection device and a speaker protection method based on the speaker protection device, in terms of amplitude protection, the embodiments of the present invention predict the amplitude of the same type of speaker through a pre-established amplitude model, and reduce the gain on a signal chain in advance when the super-amplitude is predicted, and the amplitude model itself does not need to be updated online, so that the voltage and current on a speaker coil do not need to be measured in real time, and resources are saved; in terms of temperature protection, the embodiment of the invention monitors the root mean square or mean square value of the input signal of the loudspeaker in a certain time window in real time, and reduces the gain on a signal chain before, during or after the root mean square or mean square value exceeds the threshold corresponding to the rated power of the loudspeaker, without actually estimating the temperature of a loudspeaker coil, thereby measuring the voltage and the current on the loudspeaker coil in real time. Compared with the prior art based on real-time measurement of the voltage and the current on the loudspeaker coil, the embodiment of the invention can achieve the same protection and playback effects by obviously lower software and hardware expenses; compared with the prior art based on the amplitude of the input signal of the loudspeaker, the embodiment of the invention can achieve a better playback effect while proving a more reliable protection effect.

Finally, it should be noted that: the above examples are only intended to illustrate the technical solution of the present invention, but not to limit it; although the present invention has been described in detail with reference to the foregoing embodiments, it will be understood by those of ordinary skill in the art that: the technical solutions described in the foregoing embodiments may still be modified, or some technical features may be equivalently replaced; and such modifications or substitutions do not depart from the spirit and scope of the corresponding technical solutions of the embodiments of the present invention.

Claims

1. A speaker protection device, comprising: a temperature protection module;

the output end of the first gain calculator is connected with the input end of the first gain calculator, and a first target gain value is obtained according to the root mean square or mean square value of the first audio signal to be processed in a first preset time window and a corresponding threshold value determined by the rated power of the target loudspeaker;

the input end of the first gain device is further configured to receive the first audio signal to be processed, and output the first audio signal to be processed after gain is performed on the first audio signal to be processed according to the first target gain value, and the output end of the first gain device is configured to output the processed first audio signal.

2. The apparatus of claim 1, wherein the temperature protection module further comprises a first delay;

the input end of the first delayer is used for receiving the first audio signal to be processed, and the output end of the first delayer is connected with the input end of the first booster.

3. The apparatus of claim 1, further comprising one or more sequentially connected amplitude protection modules; the input end of the amplitude protection module is connected with the temperature protection module or the amplitude protection module connected in front, and the output end of the amplitude protection module is connected with the amplitude protection module connected in back or outputs the processed audio signal;

the amplitude protection module comprises a second gain device, an amplitude model and a second gain calculator;

the input end of the amplitude model is used for receiving a second audio signal to be processed, and the output end of the amplitude model is connected with the input end of the second gain calculator; the second audio signal to be processed is an audio signal output by the temperature protection module or an audio signal output by a previously connected amplitude protection module;

the output end of the second gain calculator is connected with the input end of the second gain calculator;

the input end of the second booster is also used for receiving the second audio signal to be processed, and the output end of the second booster is connected with a post-connected amplitude protection module or outputs the processed second audio signal.

4. The apparatus of claim 3, wherein the amplitude protection module further comprises a second delay;

the input end of the second delayer is used for receiving a second audio signal to be processed, and the output end of the second delayer is connected with the input end of the second booster.

5. The apparatus of claim 3 or 4, wherein the input of the second gain calculator is further configured to receive a second audio signal to be processed.

6. The apparatus of claim 3 or 4, wherein the amplitude protection module further comprises a first peak detector;

the input end of the first peak detector is connected with the output end of the amplitude model, and the output end of the first peak detector is connected with the input end of the second gain calculator.

7. The apparatus of claim 3 or 4, wherein the amplitude protection module further comprises a second peak detector;

the input end of the second peak detector is used for receiving a second audio signal to be processed, and the output end of the second peak detector is connected with the input end of the second gain calculator.

8. The apparatus of claim 1, further comprising one or more signal protection modules connected in series; the input end of the signal protection module is connected with the temperature protection module or the signal protection module connected in front, and the output end of the signal protection module is connected with the signal protection module connected in back or outputs the processed audio signal;

the signal protection module comprises a third gain device and a third gain calculator;

the input end of the third gain calculator is used for receiving a third audio signal to be processed, and the output end of the third gain calculator is connected with the input end of the third gain calculator; the third audio signal to be processed is an audio signal output by the temperature protection module or an audio signal output by a signal protection module connected in front;

the input end of the third booster is also used for receiving a third audio signal to be processed, and the output end of the third booster is connected with a signal protection module connected behind or outputs the processed third audio signal.

9. The apparatus of claim 8, wherein the signal protection module further comprises a third peak detector;

the input end of the third peak detector is used for receiving a third audio signal to be processed, and the output end of the third peak detector is connected with the input end of the third gain calculator.

10. The apparatus of claim 8 or 9, wherein the signal protection module further comprises a third delay;

the input end of the third delayer is used for receiving a third audio signal to be processed, and the output end of the third delayer is connected with the input end of the third booster.

11. A speaker protection method based on the speaker protection apparatus according to any one of claims 1 to 10, comprising:

12. The method for protecting a loudspeaker according to claim 11, wherein the step of performing gain output on the first audio signal to be processed according to the first target gain value further comprises:

13. The method according to claim 11 or 12, wherein the outputting the first audio signal to be processed after the gain is performed on the first audio signal according to the first target gain value specifically comprises:

delaying the first audio signal to be processed for a first preset time;

14. The loudspeaker protection method according to claim 11, wherein the method further comprises:

acquiring an expected loudspeaker amplitude of a second audio signal to be processed; the second audio signal to be processed is an audio signal obtained by performing gain on the first audio signal to be processed, or is an audio signal obtained by performing secondary gain on the first audio signal to be processed;

obtaining a second target gain value according to the expected loudspeaker amplitude and the rated maximum amplitude of the target loudspeaker;

and performing gain on the second audio signal to be processed according to the second target gain value and outputting the second audio signal to be processed.

15. The loudspeaker protection method according to claim 14, wherein the step of performing gain output on the second audio signal to be processed according to the second target gain value further comprises:

16. The loudspeaker protection method according to claim 14, wherein the step of performing gain on the second audio signal to be processed according to the second target gain value and then outputting the second audio signal to be processed includes:

delaying the second audio signal to be processed for a second preset time;

17. The method according to claim 14, 15 or 16, wherein obtaining a second target gain value according to the expected horn amplitude and the target horn's rated maximum amplitude comprises:

obtaining a gain value a according to the instantaneous value of the expected horn amplitude and the rated maximum amplitude of the target horn; acquiring a gain value b according to the instantaneous value of the second audio signal to be processed and the rated maximum voltage of the current signal link;

and taking the smaller value of the gain value a and the gain value b as a second target gain value.

18. The method according to claim 14, 15 or 16, wherein obtaining a second target gain value according to the expected horn amplitude and the target horn's rated maximum amplitude comprises:

and acquiring a second target gain value according to the peak value of the expected loudspeaker amplitude and the rated maximum amplitude of the target loudspeaker.

19. The method according to claim 14, 15 or 16, wherein obtaining a second target gain value according to the peak value of the expected horn amplitude and the rated maximum amplitude of the target horn comprises:

detecting a peak value of the expected horn amplitude and a peak value of the second audio signal to be processed;

obtaining a gain value c according to the peak value of the expected loudspeaker amplitude and the rated maximum amplitude of the target loudspeaker; obtaining a gain value d according to the peak value of the second audio signal to be processed and the rated maximum voltage of the current signal link;

and taking the smaller value of the gain value c and the gain value d as a second target gain value.

20. The loudspeaker protection method according to claim 11, wherein the method further comprises:

acquiring a third target gain value according to an instantaneous value or a peak value of a third audio signal to be processed and a rated maximum voltage of a current signal link; the third audio signal to be processed is an audio signal obtained by performing gain on the first audio signal to be processed, or is an audio signal obtained by performing secondary gain on the first audio signal to be processed;

and the third audio signal to be processed is output after being gained according to the third target gain value.

21. The method according to claim 20, wherein the step of performing gain output on the third audio signal to be processed according to the third target gain value further comprises:

22. The method according to claim 20 or 21, wherein the step of performing gain on the third audio signal to be processed according to the third target gain value and outputting the third audio signal to be processed includes:

delaying the third audio signal to be processed for a third preset time;