A method and system for protection and distortion control of an audio runtime

Abstract

The application discloses a protection and distortion control method and system during sound operation, and relates to the technical field of audio processing. An audio signal and a reference signal are acquired; the reference signal is preprocessed to obtain a trigger signal of a level effective value; a trigger threshold is acquired according to the trigger signal of the level effective value; the trigger threshold is adjusted to obtain a preset trigger threshold; the preset trigger threshold is dynamically adjusted according to a voltage value corresponding to a frequency of the audio signal to obtain a voltage value corresponding to the preset trigger threshold; and the audio frequency corresponding to the voltage value corresponding to the preset trigger threshold is a protected and distortion-controlled audio signal. The application realizes dynamic change of a high-frequency cutoff frequency of an audio high-frequency unit while maintaining the loudness of a sound field restoration of a sound system, and improves the protection and distortion control accuracy of the sound in a limit operation state of high power and long time.

Description

Technical Field

[0001] This invention relates to the field of audio processing technology, and in particular to a method and system for protecting and controlling distortion during audio operation. Background Technology

[0002] The high-frequency cutoff frequency (or low-pass cutoff frequency) refers to the upper limit of audio signal reproduction in an audio system. For professional stage sound reinforcement, the upper limit is 20kHz.

[0003] The tweeter driver has a smaller diaphragm mass and lower rigidity than the mid-bass driver, and its sound frequency is higher. Therefore, it is more susceptible to the harmful effects of segmented vibration (the diaphragm is invisibly divided into multiple regions at different frequencies, and some adjacent regions vibrate in opposite phases; this type of localized vibration is called segmented vibration). This is especially pronounced when the audio system is operating at high power.

[0004] 1. The mechanical vibration of the tweeter driver's voice coil is already in a nonlinear state. The harm caused by high-frequency split vibration increases exponentially, which can lead to a deterioration in the transient response of the tweeter driver and rupture of the tweeter diaphragm.

[0005] 2. The heat loss from high-frequency split vibration cannot be ignored. The higher the frequency, the greater the heat loss, which can lead to a decrease in the conversion efficiency of the tweeter and damage to the voice coil.

[0006] 3. Under the above conditions, the distortion of the tweeter driver unit increases significantly, which seriously affects the sound quality of the audio system's sound field reproduction.

[0007] The common solution to the above problems in the past was to reduce the output power of the audio system, but this also reduced the loudness of the sound field reproduction of the audio system. Summary of the Invention

[0008] The purpose of this invention is to provide a protection and distortion control method and system for audio equipment during operation, so as to dynamically change the high-frequency cutoff frequency of the audio tweeter while maintaining the loudness of the sound field reproduction of the audio system, thereby improving the accuracy of protection and distortion control of the audio equipment under extreme operating conditions at high power for a long time.

[0009] To achieve the above objectives, embodiments of the present invention provide the following solutions:

[0010] A method for protecting and controlling distortion during audio operation, comprising:

[0011] Acquire an audio signal and a reference signal; the audio signal and the reference signal are the same signal.

[0012] The reference signal is preprocessed to obtain a trigger signal with an effective level value; the trigger signal with the effective level value is a voltage value; different frequencies of the reference signal correspond to different voltage values ​​of the trigger signal with the effective level value.

[0013] The trigger threshold is obtained based on the trigger signal with the effective level value;

[0014] The trigger threshold is adjusted to obtain a preset trigger threshold;

[0015] The preset trigger threshold is dynamically adjusted according to the voltage value corresponding to the frequency of the audio signal to obtain the voltage value corresponding to the preset trigger threshold; the audio frequency corresponding to the voltage value corresponding to the preset trigger threshold is an audio signal that has been protected and distortion controlled.

[0016] Optionally, preprocessing the reference signal to obtain a trigger signal with an effective level specifically includes:

[0017] The voltage value corresponding to the reference signal is leveled to obtain a reference signal voltage value in a linear and undistorted state;

[0018] The reference signal voltage value in the linear undistorted state is used to calculate the effective level value, and the trigger signal of the effective level value is obtained.

[0019] Optionally, obtaining the trigger threshold based on the trigger signal with the effective level value specifically includes:

[0020] Obtain the rated power of the audio system;

[0021] The output power is determined based on the trigger signal with the effective level value and the rated power.

[0022] The trigger threshold is determined based on the output power.

[0023] Optionally, the preset trigger threshold may include at most N voltage levels; the N voltage levels correspond one-to-one with the N frequency levels; the voltage levels increase progressively from the 1st to the Nth.

[0024] Optionally, dynamically adjusting the preset trigger threshold based on the voltage value corresponding to the frequency of the audio signal to obtain the voltage value corresponding to the preset trigger threshold specifically includes:

[0025] Determine the magnitude of the voltage value corresponding to the frequency of the audio signal and the voltage value of the preset trigger threshold level N;

[0026] If the voltage value corresponding to the frequency of the audio signal is less than the voltage value of the first level of the preset trigger threshold, then the voltage value corresponding to the first level of the preset trigger threshold is output.

[0027] If the voltage value corresponding to the frequency of the audio signal is greater than or equal to the voltage value of the Nth level of the preset trigger threshold, then the voltage value corresponding to the Nth level of the preset trigger threshold is output.

[0028] If the voltage value corresponding to the frequency of the audio signal is greater than the voltage value of the first level of the preset trigger threshold and less than the voltage value of the Nth level of the preset trigger threshold, then the preset trigger threshold is gradually increased from the first level to the (N-1)th level, and the voltage value corresponding to the (N-1)th level of the preset trigger threshold is output.

[0029] The voltage value corresponding to the (N-1)th level is greater than or equal to the voltage value corresponding to the frequency of the audio signal, and the frequency corresponding to the (N-2)th level is less than the voltage value corresponding to the frequency of the audio signal.

[0030] To achieve the above objectives, embodiments of the present invention also provide the following solutions:

[0031] A protection and distortion control system for audio equipment during operation, comprising:

[0032] A signal acquisition module is used to acquire an audio signal and a reference signal; the audio signal and the reference signal are the same signal.

[0033] DSP chips are used for:

[0034] The reference signal is preprocessed to obtain a trigger signal with an effective level value; the trigger signal with the effective level value is a voltage value; different frequencies of the reference signal correspond to different voltage values ​​of the trigger signal with the effective level value.

[0035] The trigger threshold is obtained based on the trigger signal with the effective level value;

[0036] The trigger threshold is adjusted to obtain a preset trigger threshold;

[0037] The preset trigger threshold is dynamically adjusted according to the voltage value corresponding to the frequency of the audio signal to obtain the voltage value corresponding to the preset trigger threshold; the audio frequency corresponding to the voltage value corresponding to the preset trigger threshold is an audio signal that has been protected and distortion controlled.

[0038] Optionally, the DSP chip includes:

[0039] The effective level calculation unit is used for:

[0040] The voltage value corresponding to the reference signal is leveled to obtain a reference signal voltage value in a linear and undistorted state;

[0041] The reference signal voltage value in the linear undistorted state is used to calculate the effective level value, and the trigger signal of the effective level value is obtained.

[0042] Optionally, the DSP chip further includes:

[0043] The trigger threshold determination unit is used for:

[0044] Obtain the rated power of the audio system;

[0045] The output power is determined based on the trigger signal with the effective level value and the rated power.

[0046] The trigger threshold is determined based on the output power.

[0047] Optionally, the preset trigger threshold may include at most N voltage levels; the N voltage levels correspond one-to-one with the N frequency levels; the voltage levels increase progressively from the 1st to the Nth.

[0048] Optionally, the DSP chip further includes:

[0049] The decision unit is used for:

[0050] Determine the magnitude of the voltage value corresponding to the frequency of the audio signal and the voltage value of the preset trigger threshold level N;

[0051] If the voltage value corresponding to the frequency of the audio signal is less than the voltage value of the first level of the preset trigger threshold, then the voltage value corresponding to the first level of the preset trigger threshold is output.

[0052] If the voltage value corresponding to the frequency of the audio signal is greater than or equal to the voltage value of the Nth level of the preset trigger threshold, then the voltage value corresponding to the Nth level of the preset trigger threshold is output.

[0053] If the voltage value corresponding to the frequency of the audio signal is greater than the voltage value of the first level of the preset trigger threshold and less than the voltage value of the Nth level of the preset trigger threshold, then the preset trigger threshold is gradually increased from the first level to the (N-1)th level, and the voltage value corresponding to the (N-1)th level of the preset trigger threshold is output.

[0054] The voltage value corresponding to the (N-1)th level is greater than or equal to the voltage value corresponding to the frequency of the audio signal, and the frequency corresponding to the (N-2)th level is less than the voltage value corresponding to the frequency of the audio signal.

[0055] In this embodiment of the invention, an audio signal and a reference signal are acquired; the reference signal is preprocessed to obtain a trigger signal with an effective level; a trigger threshold is obtained based on the trigger signal with the effective level, so that the mechanical vibration of the tweeter driver's voice coil is in a linear state, reducing the harm of high-frequency split vibration, reducing the degradation of the tweeter driver's transient response and the rupture of the tweeter diaphragm; the trigger threshold is set with high and low limits to obtain a preset trigger threshold, which reduces heat loss, improves the conversion efficiency of the tweeter driver, and reduces voice coil damage; the preset trigger threshold is dynamically adjusted according to the frequency of the audio signal to obtain a filtered audio signal. The dynamic adjustment of the preset trigger threshold can dynamically change the high-frequency cutoff frequency of the audio tweeter, significantly reducing the distortion of the tweeter driver, improving the loudness of the sound field reproduction of the audio system, and improving the protection and distortion control accuracy of the audio system under high-power, long-term extreme operating conditions. Attached Figure Description

[0056] To more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the drawings used in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For those skilled in the art, other drawings can be obtained based on these drawings without creative effort.

[0057] Figure 1 A flowchart illustrating the protection and distortion control method for audio equipment during operation provided in an embodiment of the present invention;

[0058] Figure 2 A graph of the preset trigger threshold provided in the embodiments of the present invention;

[0059] Figure 3 A schematic diagram of the structure of the protection and distortion control system for audio operation provided in an embodiment of the present invention.

[0060] Symbol explanation:

[0061] Signal acquisition module-1, DSP chip-2, effective level value calculation unit-21, trigger threshold determination unit-22, and judgment unit-23. Detailed Implementation

[0062] The technical solutions of the embodiments of the present invention will be clearly and completely described below with reference to the accompanying drawings. Obviously, the described embodiments are only some embodiments of the present invention, and not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by those skilled in the art without creative effort are within the scope of protection of the present invention.

[0063] The purpose of this invention is to provide a protection and distortion control method and system for audio equipment during operation, in order to solve the problems of existing systems being unable to dynamically change the high-frequency cutoff frequency of the audio tweeter while maintaining the loudness of the sound field reproduction of the audio system, and the low accuracy of protection and distortion control of audio equipment under high-power, long-term extreme operating conditions.

[0064] To make the above-mentioned objects, features and advantages of the present invention more apparent and understandable, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments.

[0065] Figure 1 An exemplary flow diagram of the protection and distortion control method for the aforementioned audio operation is shown. The steps are described in detail below.

[0066] Step 1: Acquire the audio signal and the reference signal; the audio signal and the reference signal are the same signal.

[0067] In one example, both the audio signal X and the reference signal Z are input signals, and the audio signal X and the reference signal Z are the same signal.

[0068] Step 2: Preprocess the reference signal to obtain the effective level trigger signal; the effective level trigger signal is a voltage value; different frequencies of the reference signal correspond to different voltage values ​​for the effective level trigger signal. Specifically, this includes:

[0069] Step 21: Adjust the voltage level of the reference signal to obtain a reference signal voltage value that is in a linear and undistorted state.

[0070] Step 22: Calculate the effective level value of the reference signal voltage value in the linear undistorted state to obtain the trigger signal with the effective level value.

[0071] In one example, both steps 21 and 22 can be executed by DSP chip 2.

[0072] Step 21 can be specifically executed by the effective level calculation unit 21 of the DSP chip 2, which can be a low-pass filter. The cutoff frequency of the low-pass filter can be preset or adjusted.

[0073] Step 22 can be specifically executed by the effective level calculation unit 21 of the DSP chip 2, which can be a low-pass filter.

[0074] The reference signal Z is equal to the audio signal X and is preprocessed by the effective level calculation unit 21 to ensure that the reference signal Z is linear and distortion-free within the DSP chip 2. The set value of the reference signal Z can be selected between -6dB and 6dB. The effective level calculation unit 21 converts the reference signal Z into an effective level trigger signal.

[0075] Step 3: Obtain the trigger threshold based on the trigger signal with the effective level value. Specifically, this includes:

[0076] Step 31: Obtain the rated power of the speaker.

[0077] Step 32: Determine the output power based on the effective level of the trigger signal and the rated power.

[0078] Step 33: Determine the trigger threshold based on the output power.

[0079] In one example, steps 31, 32, and 33 can be specifically executed by the trigger threshold determination unit 22. A trigger signal with an effective level is sent to the trigger threshold determination unit 22 and adjusted to a suitable trigger threshold. The trigger threshold is set reasonably according to the equipment performance (rated power) of the audio system; different audio equipment performances will result in significantly different trigger threshold settings.

[0080] Specifically, to set the trigger signal with an effective level of 0dB to achieve the maximum undistorted power of the audio system, the trigger threshold can be adjusted to -18dB, which corresponds to a 20kHz low-pass cutoff frequency; when the trigger signal with an effective level of -6dB, it corresponds to a 12kHz low-pass cutoff frequency.

[0081] Step 4: Adjust the trigger threshold to obtain the preset trigger threshold.

[0082] The preset trigger threshold includes up to N voltage levels; each of the N voltage levels corresponds one-to-one with a N frequency level; the voltage levels increase progressively from the 1st to the Nth.

[0083] In one example, those skilled in the art can flexibly design the value of N, such as 33, 34, 35, etc., which will not be elaborated here.

[0084] Please see Figure 2 In this embodiment of the invention, 33 is taken as an example. Figure 2 It includes 33 frequency levels. These 33 frequency levels are low-pass cutoff frequencies, ranging from 20kHz to 12kHz. The cutoff frequencies, from high to low, correspond to indices 1 to 33, where index 1 corresponds to a low-pass cutoff frequency of 20kHz, and so on, with index 33 corresponding to a low-pass cutoff frequency of 12kHz. The vertical axis represents the effective level amplitude in dB; the horizontal axis represents the frequency in Hz.

[0085] Before the audio signal X reaches the trigger threshold (e.g., -18dB), the preset trigger threshold value is 1 (trigger index 1, low-pass cutoff frequency 20kHz). When the audio signal X exceeds the trigger threshold, the low-pass cutoff frequency begins to decrease dynamically in stages. When the audio signal X reaches its maximum value (e.g., -6dB), the preset trigger threshold value is 33 (trigger index 33, and the low-pass cutoff frequency also decreases to its lowest point of 12kHz). In this way, the high-frequency components of the audio signal X delivered to the power amplifier are weakened by the low-pass filter, the breakup vibration of the tweeter diaphragm in the speaker is alleviated, the risk of diaphragm tearing is reduced (in high-power conditions), and the heat loss of the audio driver unit is reduced due to the reduction of high-frequency components, thus controlling heat generation.

[0086] Step 5: Dynamically adjust the preset trigger threshold based on the voltage value corresponding to the frequency of the audio signal to obtain the voltage value corresponding to the preset trigger threshold; the audio frequency corresponding to the voltage value of the preset trigger threshold is an audio signal that has undergone protection and distortion control. Specifically, this includes:

[0087] Step 51: Determine the magnitude of the voltage value corresponding to the frequency of the audio signal and the voltage value of the preset trigger threshold level N.

[0088] If the voltage value corresponding to the frequency of the audio signal is less than the voltage value of the first level of the preset trigger threshold, then the voltage value corresponding to the first level of the preset trigger threshold will be output.

[0089] If the voltage value corresponding to the frequency of the audio signal is greater than or equal to the voltage value of the preset trigger threshold level N, then output the voltage value corresponding to the preset trigger threshold level N.

[0090] If the voltage value corresponding to the frequency of the audio signal is greater than the voltage value of the first preset trigger threshold but less than the voltage value of the Nth preset trigger threshold, then the preset trigger threshold is gradually increased from the first level to the (N-1)th level, and the voltage value corresponding to the (N-1)th preset trigger threshold is output.

[0091] The voltage value corresponding to level N-1 is greater than or equal to the voltage value corresponding to the frequency of the audio signal, and the voltage value corresponding to level N-2 is less than the voltage value corresponding to the frequency of the audio signal.

[0092] In one example, the preset trigger threshold, which is adjusted to a suitable value, is sent to the determination unit 23. The function of the determination unit 23 is to prevent data overflow when the DSP chip 2 processes audio signals.

[0093] If the voltage value corresponding to the frequency of the audio signal is greater than or equal to the voltage value of the preset trigger threshold level 33, then the voltage value corresponding to the preset trigger threshold level 33 will be output.

[0094] In one example, N is 33. If the voltage value corresponding to the frequency of the audio signal is greater than the voltage value of the preset trigger threshold level 1 but less than the voltage value of the preset trigger threshold level 33, then the preset trigger threshold is gradually increased from level 1 to level 32, and the voltage value corresponding to the preset trigger threshold level 32 is output.

[0095] In another example, N is 8, the voltage value corresponding to level 7 is greater than or equal to the voltage value corresponding to the frequency of the audio signal, and the frequency corresponding to level 6 is less than the voltage value corresponding to the frequency of the audio signal.

[0096] By indirectly detecting the temperature of the driver unit's voice coil, and adjusting the audio power output when the voice coil temperature exceeds a preset trigger threshold, the dynamic response will suffer a 25% (or 50%) loss. This is an estimated calculation of the defects produced by the "method for detecting the temperature of the driver unit's voice coil to protect the tweeter driver unit." Loudness will also suffer a loss of approximately 25% (based on an estimate of the human ear's equal loudness curve at 100dB sound pressure). In this embodiment of the invention, after the audio system reaches the trigger threshold, the audio signal level is not reduced, so the system's dynamic response is unaffected. Since the audio signal is not limited or compressed, the audio system's power output is only related to the frequency band power of the audio signal; the "frequency band power" density for 20Hz-20kHz is 424.43, and for 20Hz-12kHz it is 424.38. The loudness loss is: (424.43-424.38) / 424.43=0.05 / 424.43=0.000118=0.0118%, which is negligible and has no impact.

[0097] In this embodiment of the invention, the audio signal level is not reduced and the high-frequency cutoff frequency is dynamically reduced. The high-frequency component delivered to the diaphragm is reduced and the high-frequency segmentation vibration of the diaphragm is effectively controlled, ensuring that the resolution of the sound field reproduction is not affected and the risk of the diaphragm being torn is greatly reduced.

[0098] In this embodiment of the invention, the high-frequency components are actively reduced, and the problem of heat generation due to friction between the diaphragm and voice coil and air molecules during high-frequency vibration is effectively solved. The maximum heat reduction is approximately (20kH^2-12kH^2) / 20kH^2 = 64%.

[0099] In this embodiment of the invention, the "RMS calculation" in the level RMS value calculation unit 21 can also use an "average value" or "peak value" algorithm.

[0100] In summary, in this embodiment of the invention, an audio signal and a reference signal are acquired; the reference signal is preprocessed to obtain a trigger signal with an effective level; a trigger threshold is obtained based on the trigger signal with the effective level, so that the mechanical vibration of the tweeter driver's voice coil is in a linear state, reducing the harm of high-frequency split vibration, reducing the degradation of the tweeter driver's transient response and the rupture of the tweeter diaphragm; a high or low limit is set on the trigger threshold to obtain a preset trigger threshold, which reduces heat loss, improves the conversion efficiency of the tweeter driver, and reduces voice coil damage; the preset trigger threshold is dynamically adjusted according to the frequency of the audio signal to obtain a filtered audio signal. The dynamic adjustment of the preset trigger threshold can dynamically change the high-frequency cutoff frequency of the audio tweeter, significantly reducing the distortion of the tweeter driver, improving the loudness of the sound field reproduction of the audio system, and improving the protection and distortion control accuracy of the audio system under high-power, long-term extreme operating conditions.

[0101] To achieve the above objectives, embodiments of the present invention also provide the following solutions:

[0102] For an audio protection and distortion control system during operation, please refer to [link / reference]. Figure 3 It includes: signal acquisition module 1 and DSP chip 2.

[0103] Signal acquisition module 1 is used to acquire audio signals and reference signals; the audio signal and reference signal are the same signal.

[0104] DSP chip 2 is used for:

[0105] The reference signal is preprocessed to obtain the trigger signal with effective level; the trigger signal with effective level is a voltage value; different frequencies of the reference signal correspond to different voltage values ​​of the trigger signal with effective level.

[0106] The trigger threshold is obtained based on the effective level of the trigger signal.

[0107] The trigger threshold is adjusted to obtain the preset trigger threshold.

[0108] The preset trigger threshold is dynamically adjusted based on the voltage value corresponding to the frequency of the audio signal to obtain the voltage value corresponding to the preset trigger threshold; the audio frequency corresponding to the voltage value corresponding to the preset trigger threshold is the audio signal that has been protected and distortion controlled.

[0109] DSP chip 2 includes:

[0110] The effective level calculation unit 21 is used for:

[0111] The voltage value corresponding to the reference signal is leveled to obtain a reference signal voltage value in a linear and undistorted state.

[0112] The reference signal voltage value in a linear, undistorted state is used to calculate the effective level value, and the trigger signal with the effective level value is obtained.

[0113] DSP chip 2 also includes:

[0114] Trigger threshold determination unit 22 is used for:

[0115] Obtain the rated power of the audio system.

[0116] The output power is determined based on the effective level of the trigger signal and the rated power.

[0117] The trigger threshold is determined based on the output power.

[0118] The preset trigger threshold includes up to N voltage levels; each of the N voltage levels corresponds one-to-one with a N frequency level; the voltage levels increase progressively from the 1st to the Nth.

[0119] DSP chip 2 also includes:

[0120] The determination unit 23 is used for:

[0121] Determine the magnitude of the voltage value corresponding to the frequency of the audio signal and the voltage value of the preset trigger threshold level N.

[0122] If the voltage value corresponding to the frequency of the audio signal is less than the voltage value of the first level of the preset trigger threshold, then the voltage value corresponding to the first level of the preset trigger threshold will be output.

[0123] If the voltage value corresponding to the frequency of the audio signal is greater than or equal to the voltage value of the preset trigger threshold level N, then output the voltage value corresponding to the preset trigger threshold level N.

[0124] If the voltage value corresponding to the frequency of the audio signal is greater than the voltage value of the first preset trigger threshold but less than the voltage value of the Nth preset trigger threshold, then the preset trigger threshold is gradually increased from the first level to the (N-1)th level, and the voltage value corresponding to the (N-1)th preset trigger threshold is output.

[0125] The voltage value corresponding to level N-1 is greater than or equal to the voltage value corresponding to the frequency of the audio signal, and the voltage value corresponding to level N-2 is less than the voltage value corresponding to the frequency of the audio signal.

[0126] The various embodiments in this specification are described in a progressive manner, with each embodiment focusing on its differences from other embodiments. Similar or identical parts between embodiments can be referred to interchangeably. For the systems disclosed in the embodiments, since they correspond to the methods disclosed in the embodiments, the descriptions are relatively simple; relevant parts can be referred to the method section.

[0127] This document uses specific examples to illustrate the principles and implementation methods of the embodiments of the present invention. The descriptions of the embodiments above are only for the purpose of helping to understand the methods and core ideas of the embodiments of the present invention. At the same time, for those skilled in the art, there will be changes in specific implementation methods and application scope based on the ideas of the embodiments of the present invention. In summary, the content of this specification should not be construed as a limitation on the embodiments of the present invention.

Claims

1. A method for protection and distortion control during audio operation, characterized in that, include: Acquire an audio signal and a reference signal; the audio signal and the reference signal are the same signal. The reference signal is preprocessed to obtain a trigger signal with an effective level value; The trigger signal for the effective level value is a voltage value; The different frequencies of the reference signal correspond to different voltage values ​​of the trigger signal for the effective level value; The trigger threshold is obtained based on the trigger signal with the effective level value; The effective level trigger signal is sent to the trigger threshold determination unit and the trigger threshold is adjusted. Specifically, the effective level trigger signal is set to 0dB when the audio system reaches the maximum undistorted power, and the trigger threshold is adjusted to -18dB, which corresponds to a 20kHz low-pass cutoff frequency; when the effective level trigger signal reaches -6dB, it corresponds to a 12kHz low-pass cutoff frequency. The trigger threshold is adjusted to obtain a preset trigger threshold; The preset trigger threshold includes at most N voltage levels; each of the N voltage levels corresponds one-to-one with a N frequency level; the voltage levels increase progressively from the 1st to the Nth. The preset trigger threshold is dynamically adjusted according to the voltage value corresponding to the frequency of the audio signal to obtain the voltage value corresponding to the preset trigger threshold; the audio frequency corresponding to the voltage value corresponding to the preset trigger threshold is an audio signal that has been protected and distortion controlled. Specifically, this includes: determining the magnitude of the voltage value corresponding to the frequency of the audio signal and the voltage value of the preset trigger threshold at level N; If the voltage value corresponding to the frequency of the audio signal is less than the voltage value of the first level of the preset trigger threshold, then the voltage value corresponding to the first level of the preset trigger threshold is output. If the voltage value corresponding to the frequency of the audio signal is greater than or equal to the voltage value of the Nth level of the preset trigger threshold, then the voltage value corresponding to the Nth level of the preset trigger threshold is output. If the voltage value corresponding to the frequency of the audio signal is greater than the voltage value of the first level of the preset trigger threshold and less than the voltage value of the Nth level of the preset trigger threshold, then the preset trigger threshold is gradually increased from the first level to the (N-1)th level, and the voltage value corresponding to the (N-1)th level of the preset trigger threshold is output. The voltage value corresponding to the (N-1)th level is greater than or equal to the voltage value corresponding to the frequency of the audio signal, and the frequency corresponding to the (N-2)th level is less than the voltage value corresponding to the frequency of the audio signal.

2. The protection and distortion control method for audio equipment during operation according to claim 1, characterized in that, Preprocessing the reference signal to obtain the trigger signal with an effective level specifically includes: The voltage value corresponding to the reference signal is leveled to obtain a reference signal voltage value in a linear and undistorted state; The reference signal voltage value in the linear undistorted state is used to calculate the effective level value, and the trigger signal of the effective level value is obtained.

3. The protection and distortion control method for audio equipment during operation according to claim 1, characterized in that, Obtaining the trigger threshold based on the trigger signal with the effective level specifically includes: Obtain the rated power of the audio system; The output power is determined based on the trigger signal with the effective level value and the rated power. The trigger threshold is determined based on the output power.

4. A protection and distortion control system for audio equipment during operation, characterized in that, include: A signal acquisition module is used to acquire an audio signal and a reference signal; the audio signal and the reference signal are the same signal. DSP chips are used for: The reference signal is preprocessed to obtain a trigger signal with an effective level value; the trigger signal with the effective level value is a voltage value. The different frequencies of the reference signal correspond to different voltage values ​​of the trigger signal for the effective level value; The trigger threshold is obtained based on the trigger signal with the effective level value; The effective level trigger signal is sent to the trigger threshold determination unit and the trigger threshold is adjusted. Specifically, the effective level trigger signal is set to 0dB when the audio system reaches the maximum undistorted power, and the trigger threshold is adjusted to -18dB, which corresponds to a 20kHz low-pass cutoff frequency; when the effective level trigger signal reaches -6dB, it corresponds to a 12kHz low-pass cutoff frequency. The trigger threshold is adjusted to obtain a preset trigger threshold; The preset trigger threshold includes at most N voltage levels; each of the N voltage levels corresponds one-to-one with a N frequency level; the voltage levels increase progressively from the 1st to the Nth. The preset trigger threshold is dynamically adjusted according to the voltage value corresponding to the frequency of the audio signal to obtain the voltage value corresponding to the preset trigger threshold; the audio frequency corresponding to the voltage value corresponding to the preset trigger threshold is an audio signal that has been protected and distortion controlled. The DSP chip also includes: The decision unit is used for: Determine the magnitude of the voltage value corresponding to the frequency of the audio signal and the voltage value of the preset trigger threshold level N; If the voltage value corresponding to the frequency of the audio signal is less than the voltage value of the first level of the preset trigger threshold, then the voltage value corresponding to the first level of the preset trigger threshold is output. If the voltage value corresponding to the frequency of the audio signal is greater than or equal to the voltage value of the Nth level of the preset trigger threshold, then the voltage value corresponding to the Nth level of the preset trigger threshold is output. If the voltage value corresponding to the frequency of the audio signal is greater than the voltage value of the first level of the preset trigger threshold and less than the voltage value of the Nth level of the preset trigger threshold, then the preset trigger threshold is gradually increased from the first level to the (N-1)th level, and the voltage value corresponding to the (N-1)th level of the preset trigger threshold is output. The voltage value corresponding to the (N-1)th level is greater than or equal to the voltage value corresponding to the frequency of the audio signal, and the frequency corresponding to the (N-2)th level is less than the voltage value corresponding to the frequency of the audio signal.

5. The protection and distortion control system for audio operation according to claim 4, characterized in that, The DSP chip includes: The effective level calculation unit is used for: The voltage value corresponding to the reference signal is leveled to obtain a reference signal voltage value in a linear and undistorted state; The reference signal voltage value in the linear undistorted state is used to calculate the effective level value, and the trigger signal of the effective level value is obtained.

6. The protection and distortion control system for audio operation according to claim 4, characterized in that, The DSP chip also includes: The trigger threshold determination unit is used for: Obtain the rated power of the audio system; The output power is determined based on the trigger signal with the effective level value and the rated power. The trigger threshold is determined based on the output power.

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