A power amplifier module circuit for a mixing console

Abstract

The invention relates to the technical fields of electronic circuit manufacturing, electronic equipment manufacturing, amplification control and electro-acoustic musical instruments, and provides a power amplifier module circuit of a mixing console. The circuit obtains an electric guitar analog audio signal output by buffering and amplifying a received electric guitar signal, performs amplitude limiting after receiving the electric guitar analog audio signal, obtains an electric guitar analog audio signal after amplitude limiting, performs positive and reverse processing after receiving the electric guitar analog audio signal after amplitude limiting, obtains positive and reverse feedback signals, outputs an amplitude limiting adjustment signal after comparing the positive and reverse feedback signals with the electric guitar analog audio signal, generates positive and reverse drive signal outputs according to the amplitude limiting adjustment signal, performs differential amplification after receiving the positive and reverse drive signals, and obtains an electric guitar music signal for connecting to a sound box for playing, thereby solving the technical problems existing in the existing power amplifier circuit, such as the input signal is easily distorted or clipped, the noise control effect is poor during amplification, and the amplitude limiting control is unstable.

Description

Technical Field

[0001] The present invention relates to the technical fields of electronic circuit manufacturing, electronic equipment manufacturing, amplification control and electro-acoustic musical instruments, and in particular to a power amplifier module circuit of a mixing console. Background Art

[0002] In audio equipment, electric guitar signals have unique characteristics: they have a large dynamic range, a wide frequency range, and are easily interfered by noise. Therefore, in mixers and audio power amplifiers, it is necessary to amplify electric guitar signals with high fidelity through power amplifier circuits. However, due to the large dynamic range of electric guitar signals, the input amplitude may increase significantly in an instant. When processing large dynamic range signals, traditional amplifiers are difficult to effectively limit the input signal amplitude, which can easily lead to overload of the power amplifier circuit, clipping distortion, and damage to the sound quality. In addition, in traditional amplifier circuits, the input buffer and amplifier parts are easily affected by external electromagnetic interference and internal noise, especially when high gain amplification is more likely to amplify noise, resulting in deterioration of output sound quality. Moreover, traditional power amplifiers usually use a fixed threshold limiter circuit, which cannot dynamically adjust the limiter state according to the actual input signal. Faced with complex electric guitar signals, large dynamic range signals may not be accurately controlled, limiting the scope of application of the amplifier. In addition, in existing power amplifiers, the forward and reverse drive signals are prone to imbalance, introducing common mode noise, causing distortion and increased background noise in the audio output, especially when high power output is more obvious.

[0003] In summary, the power amplifier circuit in the prior art has technical problems such as easy distortion or clipping of the input signal, poor noise control effect during the amplification process, and unstable limit control. Summary of the invention

[0004] The invention provides a power amplifier module circuit of a mixing console to solve the technical problems existing in the prior power amplifier circuit, such as easy distortion or clipping of input signals, poor noise control effect during amplification, unstable limit control, etc.

[0005] The present invention provides a power amplifier module circuit of a mixing console, comprising:

[0006] The buffer amplifier unit circuit is used to receive the real-time input electric guitar signal, buffer it and amplify it, so as to obtain an electric guitar analog audio signal output that is in phase and frequency with the input electric guitar signal and has an amplified amplitude;

[0007] A limiting protection circuit is electrically connected to the output end of the buffer amplifier unit circuit, and is used for receiving the electric guitar analog audio signal and performing limiting processing to obtain a limited electric guitar analog audio signal;

[0008] A feedback comparison and signal adjustment unit circuit is electrically connected to the output end of the amplitude limiting protection circuit, and is used to receive the amplitude limited electric guitar analog audio signal and perform positive and reverse processing to obtain positive and reverse feedback signals, and compare the positive and reverse feedback signals with the electric guitar analog audio signal obtained by buffering and amplifying the buffer amplifier unit circuit, and then output an amplitude limiting adjustment signal;

[0009] A power amplification driving unit circuit, electrically connected to the limit adjustment signal output terminal of the feedback comparison and signal adjustment unit circuit, and used for generating positive and reverse driving signal outputs according to the limit adjustment signal;

[0010] The power amplifier output unit circuit is electrically connected to the output end of the power amplifier driving unit circuit, and is used to receive the positive and reverse driving signals and then differentially amplify the positive and reverse driving signals to obtain an electric guitar music signal for connecting to a speaker for playing.

[0011] Compared with the prior art, the present invention has the following beneficial effects:

[0012] The present invention provides a power amplifier module circuit of a mixing console. The power amplifier module circuit includes a buffer amplifier unit circuit, which is used to receive a real-time input electric guitar signal, perform buffering and amplification, so as to obtain an electric guitar analog audio signal output that is in phase and has the same frequency as the input electric guitar signal and has an amplified amplitude. A limiter protection circuit is further provided, which is electrically connected to the output end of the buffer amplifier unit circuit, and is used to perform limiter processing after receiving the electric guitar analog audio signal, so as to obtain the limited electric guitar analog audio signal. A feedback comparison and signal adjustment unit circuit is further provided, which is electrically connected to the output end of the limiter protection circuit, and is used to perform positive and reverse processing after receiving the limited electric guitar analog audio signal, so as to obtain positive and reverse feedback signals, and the positive and reverse feedback signals are compared with the buffer amplifier unit circuit. After comparing the electric guitar analog audio signal obtained by buffering and amplifying the large unit circuit, a limiting adjustment signal is output, and then a power amplifier driving unit circuit is set, which is electrically connected to the limiting adjustment signal output end of the feedback comparison and signal adjustment unit circuit, and is used to generate positive and reverse driving signal outputs according to the limiting adjustment signal. Then a power amplifier output unit circuit is set, which is electrically connected to the output end of the power amplifier driving unit circuit, and is used to receive the positive and reverse driving signals and then perform differential amplification on the positive and reverse driving signals to obtain an electric guitar music signal for connecting to a speaker for playing, thereby solving the technical problems of the existing power amplifier circuit, such as the input signal is easily distorted or clipped, the noise control effect is poor during amplification, and the limiting control is unstable. BRIEF DESCRIPTION OF THE DRAWINGS

[0013] The drawings described herein are used to provide a further understanding of the present invention and constitute a part of the present invention. The exemplary embodiments of the present invention and their description are used to explain the present invention and do not constitute an improper limitation of the present invention. Some specific embodiments of the present invention will be described in detail in an exemplary and non-restrictive manner with reference to the drawings. The same reference numerals in the drawings indicate the same or similar components or parts. It should be understood by those skilled in the art that these drawings are not necessarily drawn to scale. In the drawings:

[0014] Figure 1 It is a circuit structure schematic diagram of a power amplifier module circuit of a mixer according to an embodiment of the present invention;

[0015] Figure 2 It is another circuit structure schematic diagram of the power amplifier module circuit of the mixer according to an embodiment of the present invention.

[0016] Description of reference numerals:

[0017] 100, buffer amplifier unit circuit; 200, limit protection circuit; 300, feedback comparison and signal adjustment unit circuit; 400, power amplifier drive unit circuit; 500, power amplifier output unit circuit; 600, output filter unit circuit. DETAILED DESCRIPTION

[0018] In order to enable those skilled in the art to better understand the scheme of the present invention, the technical scheme in the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings in the embodiment of the present invention. Obviously, the described embodiment is only an embodiment of a part of the present invention, not all embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative work should fall within the scope of protection of the present invention.

[0019] See also Figure 1-Figure 2 , an embodiment of the present invention provides a power amplifier module circuit of a mixing console, comprising:

[0020] The buffer amplifier unit circuit is used to receive the real-time input electric guitar signal, buffer it and amplify it, so as to obtain an electric guitar analog audio signal output that is in phase and frequency with the input electric guitar signal and has an amplified amplitude;

[0021] A limiting protection circuit is electrically connected to the output end of the buffer amplifier unit circuit, and is used for receiving the electric guitar analog audio signal and performing limiting processing to obtain a limited electric guitar analog audio signal;

[0022] A feedback comparison and signal adjustment unit circuit is electrically connected to the output end of the amplitude limiting protection circuit, and is used to receive the amplitude limited electric guitar analog audio signal and perform positive and reverse processing to obtain positive and reverse feedback signals, and compare the positive and reverse feedback signals with the electric guitar analog audio signal obtained by buffering and amplifying the buffer amplifier unit circuit, and then output an amplitude limiting adjustment signal;

[0023] A power amplification driving unit circuit, electrically connected to the limit adjustment signal output terminal of the feedback comparison and signal adjustment unit circuit, and used for generating positive and reverse driving signal outputs according to the limit adjustment signal;

[0024] The power amplifier output unit circuit is electrically connected to the output end of the power amplifier driving unit circuit, and is used to receive the positive and reverse driving signals and then differentially amplify the positive and reverse driving signals to obtain an electric guitar music signal for connecting to a speaker for playing.

[0025] It should be noted that, in this embodiment, the buffer amplifier unit circuit receives the electric guitar signal and buffers and amplifies it. Through buffer amplification, the electric guitar signal can maintain the same phase, the same frequency and the amplitude is amplified. In this way, the dynamic range of the electric guitar signal can be effectively amplified, while avoiding the overload problem caused by the sudden increase of the input amplitude. The buffer circuit helps to protect the subsequent circuit from the influence of the input signal fluctuation, thereby effectively reducing the clipping distortion phenomenon that may occur in the traditional circuit. In addition, the limiter protection circuit receives the buffered amplified signal and performs a limiter processing to limit the amplitude of the signal to avoid distortion and clipping caused by excessive signal amplitude, thereby solving the problem that the traditional power amplifier cannot effectively limit the amplitude of the large dynamic range signal and avoid signal overload and clipping distortion. The feedback comparison and signal adjustment unit circuit processes the limited electric guitar signal in the forward and reverse directions, and compares the feedback signal with the buffered amplified signal, and outputs a limiter adjustment signal, so that the circuit can dynamically adjust the limiter state according to the change of the input signal, avoiding the limitation that the fixed threshold limiter circuit in the traditional amplifier cannot adapt to the changing input. The power amplifier drive unit circuit receives the limiter adjustment signal and generates forward and reverse drive signals. Through precise control of the drive unit, the power amplifier can dynamically adjust the drive output according to the feedback of the adjustment signal to ensure that the signal is not distorted during the amplification process and avoid the common mode noise and background noise problems caused by unbalanced drive in traditional amplifiers. The power amplifier output unit circuit receives the positive and reverse drive signals and performs differential amplification to output the electric guitar music signal. Through differential amplification, the signal is effectively amplified and the noise interference is suppressed, ensuring the high quality of the final output signal, which is suitable for connecting to the speaker for playback. Differential amplification can reduce noise interference and improve signal stability and sound quality.

[0026] In this embodiment, the signal distortion and clipping problems caused by the large dynamic range in the traditional power amplifier circuit can be solved through the cooperation of the buffer amplifier and the limit protection circuit. The input signal is precisely controlled to avoid distortion caused by excessive input amplitude. The feedback comparison and signal adjustment unit circuit provides the ability of dynamic adjustment, so that the limit control can be adjusted according to the changes of the actual input signal, avoiding the limitations brought by the fixed limit threshold in the traditional power amplifier, and ensuring the flexibility and stability of signal processing. In traditional amplifiers, high gain amplification will amplify noise, especially when the input signal is weak, the noise will be more obvious. In this embodiment, through differential amplification, feedback mechanism and fine control, noise interference can be effectively reduced, and the clarity and stability of sound quality can be improved. Due to the differential amplification design of the power amplifier drive unit and the power amplifier output unit, the influence of common mode noise can be effectively suppressed, distortion and background noise caused by unbalanced drive can be avoided, and the audio quality can be ensured to be stable at high power output. In general, this embodiment can solve the problems of signal distortion, noise interference and unstable limiting control in existing power amplifiers by introducing dynamic limiting adjustment, effective noise control and differential amplification design, and achieve high-fidelity output of sound quality.

[0027] In some preferred embodiments, the power amplifier module circuit of the mixing console also includes: an output filter unit circuit, the output filter unit circuit is connected to the power amplifier output unit circuit to obtain the electric guitar music signal; before the electric guitar music signal is input into the speaker for playing, the output filter unit circuit filters the electric guitar music signal to filter out the high-frequency noise in the electric guitar music signal. It should be noted that even in the high-fidelity power amplification process, the high-frequency noise in the signal may still exist. If these noises are not filtered out, unnecessary noise or harsh high-frequency components will be introduced into the audio signal, affecting the clarity and realism of the sound quality. In this embodiment, by filtering the electric guitar music signal before the electric guitar music signal is input into the speaker for playing, the output filter unit circuit filters the electric guitar music signal to filter out the high-frequency noise in the electric guitar music signal, so as to effectively suppress these high-frequency noises and ensure that the final output audio signal is purer and clearer. The power amplifier module circuit of the mixing console also includes an audio interface, the audio interface is connected to the output end of the output filter unit circuit, and the electric guitar music signal after filtering out the high-frequency noise is connected to the speaker for playing. It should be noted that the main function of the audio interface is to serve as a bridge between the power amplifier module and the speaker to ensure that the filtered electric guitar music signal can be efficiently and stably transmitted to the speaker for playback. The audio interface can be a standardized connection method (such as RCA, XLR, etc.), which is convenient for matching and connecting with the speaker equipment, so as to ensure that the signal can be correctly transmitted to the speaker. Exemplarily, the output filter unit circuit may include an inductor L1, an inductor L2, an inductor L3 and an inductor L4 connected to the four output ends of the power amplifier output unit circuit. The inductor L1, the inductor L2, the inductor L3 and the inductor L4 filter the electric guitar music signal before inputting the electric guitar music signal into the speaker for playback to filter out the high-frequency noise in the electric guitar music signal. The inductor L1 and the inductor L3 are connected to the positive poles of the audio interfaces J1 and J2, and the inductor L2 and the inductor L4 are connected to the negative poles of the audio interfaces J1 and J2. The audio interfaces J1 and J2 connect the electric guitar music signal after filtering out the high-frequency noise to the speaker for playback.

[0028] In some preferred embodiments, the buffer amplifier unit circuit includes an operational amplifier U1, and the signal input end of the operational amplifier U1 receives the real-time input electric guitar signal Input for buffering and amplification, so as to obtain an electric guitar analog audio signal output that is in phase, has the same frequency and has an amplified amplitude as the input electric guitar signal Input. It should be noted that the operational amplifier has a very high input impedance and a low output impedance, which enables it to effectively receive signals from the electric guitar without introducing the load effect of the signal source (such as a guitar pickup). The high input impedance can ensure that the transmission of the signal source is not affected, while the low output impedance ensures that the subsequent circuit can stably receive the signal without distortion or attenuation. This is especially important for signals with a large dynamic range such as electric guitars, which can prevent the signal from being excessively attenuated or distorted. In addition, the operational amplifier can be used to buffer the signal to avoid being affected by external loads or changes in circuit impedance during signal transmission. Electric guitar signals are usually weak and sensitive to impedance. The operational amplifier can provide high input impedance and uniform signal output to ensure stable signal transmission and reduce noise and distortion caused by circuit mismatch. In addition, the operational amplifier can adjust the gain according to the design requirements to achieve appropriate amplification of the electric guitar signal. Through the operational amplifier, the amplitude of the output signal can be accurately controlled while ensuring that the signal is in phase and the frequency remains unchanged. This is crucial for processing electric guitar signals, and can provide sufficient amplification without introducing obvious distortion, avoiding the distortion that may be introduced by traditional amplifiers due to excessive gain. Among them, Input is used to represent the electric guitar signal input in real time.

[0029] In some preferred embodiments, the amplitude limiting protection circuit includes a gain amplifier circuit and an amplitude limiting protection circuit; the input end of the gain amplifier circuit is electrically connected to the output end of the electric guitar analog audio signal of the operational amplifier U1, and is used to receive the electric guitar analog audio signal and then perform gain amplification; the output end of the gain amplifier circuit is electrically connected to the input end of the amplitude limiting protection circuit, and the amplitude limiting protection circuit receives the electric guitar analog audio signal after gain amplification and then performs amplitude limiting protection processing to obtain the output of the electric guitar analog audio signal after amplitude limiting. It should be noted that the electric guitar signal usually has a low amplitude, especially it may be reduced due to the attenuation of various circuits during the transmission process. The design of the gain amplifier circuit can be used to properly amplify the signal to ensure that the signal has sufficient strength in the subsequent processing stage, provide high-quality input for the amplitude limiting protection circuit, and ensure that the amplitude limiting process can be accurately executed. The main function of the amplitude limiting protection circuit is to avoid the input signal being too large to cause the circuit to overload, and to prevent the audio signal output by the power amplifier from being distorted under the condition of large amplitude input. The dynamic range of the electric guitar signal is large, and the signal amplitude may increase significantly in an instant. The traditional amplifier circuit cannot handle such a large dynamic range, which is easy to cause clipping distortion. The limiter protection circuit can protect subsequent circuits by limiting the maximum amplitude of the signal, avoiding signal distortion and maintaining sound quality. In this embodiment, the gain amplifier circuit and the limiter protection circuit work together to ensure that the signal can be sufficiently amplified and will not get out of control when an overly strong signal appears. The gain amplifier circuit provides the necessary gain for the signal, while the limiter protection circuit ensures that the signal will not be distorted or clipped due to excessive amplitude. The combination of the two can not only ensure the amplification effect of the signal, but also prevent distortion caused by excessive amplification, thereby optimizing the signal quality.

[0030] In some preferred embodiments, the gain amplifier circuit includes an operational amplifier U2; the input end of the operational amplifier U2 is the input end of the gain amplifier circuit, and the output end of the operational amplifier U2 is the output end of the gain amplifier circuit. The amplitude limiting protection circuit includes a diode group D3 with anodes and cathodes connected in series; the series end of two diodes in the diode group D3 with anodes and cathodes connected in series is the input end of the amplitude limiting protection circuit, the non-series cathode of one diode in the diode group D3 with anodes and cathodes connected in series is the first output end of the amplitude limiting protection circuit that outputs the electric guitar simulated audio signal after amplitude limiting, and the non-series anode of one diode in the diode group D3 with anodes and cathodes connected in series is the second output end of the amplitude limiting protection circuit that outputs the electric guitar simulated audio signal after amplitude limiting. It should be noted that the operational amplifier U2 can provide high gain amplification to ensure that the input signal (electric guitar simulated audio signal) is effectively amplified. For inputs such as electric guitar signals with a large dynamic range, the operational amplifier can ensure that the signal is uniformly amplified while avoiding distortion. The operational amplifier U2 can adapt to input signals of different strengths by adjusting its gain control, thereby ensuring that the output amplitude of the signal is suitable for processing by subsequent circuits. This flexibility is critical to audio systems because the strength of an electric guitar signal may vary greatly at different moments in time. The operational amplifier setting can ensure that the signal is neither too weak nor too strong, thereby avoiding over-amplification or attenuation, and ensuring that the amplified signal is suitable for subsequent limiting protection processing. The diode is a typical limiting element. Through its unidirectional conductive characteristics, when the signal exceeds a certain voltage, the diode will begin to conduct, limiting the signal amplitude, and preventing the signal from being too strong and causing overload and distortion. In this embodiment, the design of the diode group (D3) with anodes and cathodes connected in series can accurately control the amplitude of the signal. When the signal exceeds the conduction threshold of the diode, the signal will be limited to a certain range. In this way, the amplitude of the electric guitar signal will not exceed the set limit, thereby avoiding clipping distortion and amplifier overload. By setting the diode group with anodes and cathodes connected in series, bidirectional limiting can be achieved to limit the signal amplitude in both positive and negative directions. This is critical for processing electric guitar signals because electric guitar signals may have large changes in positive and negative polarity. Through this bidirectional limiting method, it can be ensured that the signal can be effectively limited in both polarity directions. The series connection of the diode group can quickly respond to the amplitude change of the input signal. Once the signal amplitude exceeds the set range, the diode will quickly turn on, thereby ensuring that the signal limiting processing is very timely and accurate. This can effectively prevent excessive changes in the signal from causing adverse effects on subsequent circuits, and improve the stability of the system and the accuracy of signal processing. In addition, the non-series cathode of one diode in the diode group outputs the limited signal, and the non-series anode of the other diode outputs the limited signal, thereby allowing the signal to obtain clear reverse limiting in two directions at the output end, providing reverse limiting signals in different directions for subsequent circuit processing.

[0031] In some preferred embodiments, the feedback comparison and signal adjustment unit circuit includes a feedback signal generation circuit and a comparison adjustment circuit; the feedback signal generation circuit is electrically connected to the output end of the amplitude limiting protection circuit, and is used to receive the electric guitar simulated audio signal after amplitude limiting, and then perform positive and reverse processing to obtain positive and reverse feedback signals and output them to the comparison adjustment circuit; the comparison signal input end of the comparison adjustment circuit is electrically connected to the output end of the electric guitar simulated audio signal of the operational amplifier U1 and the output end of the feedback signal generation circuit that outputs the positive and reverse feedback signals, and is used to compare the received positive and reverse feedback signals with the electric guitar simulated audio signal, and then output the amplitude limiting adjustment signal. It should be noted that the function of the feedback signal generation circuit is to receive the amplitude limiting signal from the amplitude limiting protection circuit and process it into positive and negative feedback signals. After the electric guitar signal passes through the amplitude limiting protection circuit, there may be problems due to amplitude changes or large dynamic range, so it is necessary to adjust and control the amplitude and characteristics of the signal through a feedback mechanism to ensure that it meets the system requirements. Through positive and negative feedback signals, the signal can be adjusted in all directions. This bidirectional feedback design ensures that the system's signal processing is not limited to a single direction, but can be precisely adjusted according to the different directions of signal changes to provide more flexible feedback control. The comparison adjustment circuit receives the electric guitar analog audio signal output by the operational amplifier U1 and the positive and negative feedback signals from the feedback signal generation circuit, and compares them. The purpose of this comparison is to monitor the difference between the input signal and the feedback signal in real time, and output the corresponding limit adjustment signal according to the comparison result. By comparing the input signal with the feedback signal, the amplitude of the signal can be detected and adjusted in real time to ensure that the signal will not be distorted or over-amplified during the amplification and limiting process. This comparison mechanism can accurately control the signal processing process and avoid sound quality distortion caused by improper amplitude in traditional circuits. In this way, the circuit can respond to the dynamic changes of the electric guitar signal in real time and automatically adjust the limit control to ensure that the signal amplitude is appropriately limited during the signal processing process without introducing distortion. The dynamic range of the electric guitar signal is large and changes rapidly, and it is difficult for traditional fixed limit circuits to maintain ideal performance under different input conditions. Through the design of comparison and feedback adjustment, the limiting state can be dynamically adjusted according to the actual input changes, so that the power amplifier module can more flexibly respond to different input signal changes and adapt to more usage scenarios and complex signal conditions. Through real-time feedback control, the signal amplitude, frequency response and overall processing effect can be adjusted more accurately. This precise feedback adjustment not only helps to ensure high-fidelity amplification of electric guitar signals, but also effectively avoids unnecessary clipping or distortion, providing clearer and more realistic audio output.

[0032] In some preferred embodiments, the feedback signal generating circuit includes an operational amplifier U3 and an operational amplifier U4; the in-phase end of the operational amplifier U3 is the first receiving end for receiving the electric guitar simulated audio signal after the amplitude limitation, the inverting end of the operational amplifier U3 is connected to the in-phase end of the operational amplifier U4, and the inverting end of the operational amplifier U4 is the second receiving end for receiving the electric guitar simulated audio signal after the amplitude limitation; the output ends of the operational amplifier U3 and the operational amplifier U4 output the positive and negative feedback signals to the comparison and adjustment circuit. It should be noted that the in-phase end of the operational amplifier U3 is the first receiving end for receiving the electric guitar simulated audio signal after the amplitude limitation, the in-phase end of the operational amplifier U4 is the second receiving end for receiving the electric guitar simulated audio signal after the amplitude limitation, and the inverting end of the operational amplifier U3 is connected to the in-phase end of the operational amplifier U4, so that the operational amplifiers U3 and U4 can generate positive and negative feedback signals. This design can provide accurate feedback signals for the subsequent comparison and adjustment circuit, so that the circuit can make adjustments according to the comparison results of the input signal and the feedback signal. Positive and negative feedback signals are important tools for controlling signal amplitude and waveform. They can effectively adjust the output of the signal and ensure signal processing accuracy and dynamic control. The dynamic range of electric guitar signals is very large, and instantaneous signal changes may cause distortion of sound quality or overload of the amplifier. Through the design of positive and negative feedback, dynamic adjustment can be achieved, and the input and output characteristics of the amplifier can be automatically adjusted in real time according to the changes in the signal. Precise control of the feedback signal can effectively cope with the fluctuations of the input signal, ensuring that the power amplifier can still maintain high-quality audio output when processing signals with different dynamic ranges.

[0033] In some preferred embodiments, the comparison adjustment circuit includes an operational amplifier U7, a diode D1, a diode D2, a resistor R1, a resistor R2, a resistor R3 and a resistor R4; the input end of the operational amplifier U7 is the comparison signal input end of the comparison adjustment circuit, which is connected to the output end of the electric guitar analog audio signal of the operational amplifier U1 and the output ends of the operational amplifier U3 and the operational amplifier U4 that output the positive and negative feedback signals; the diode D1 and the diode D2 are arranged inside the operational amplifier U7, the anodes of the diode D1 and the diode D2 are connected to one end of the resistor R2, and the other end of the resistor R2 is grounded; the cathode of the diode D1 is connected to the inverting end of the operational amplifier U7, one end of the resistor R1 and one end of the resistor R4, the other end of the resistor R1 is grounded, and the other end of the resistor R4 is the output end of the comparison adjustment circuit that outputs the limiting adjustment signal; the cathode of the diode D2 is connected to the in-phase end of the operational amplifier U7 and one end of the resistor R3, and the other end of the resistor R3 is grounded. It should be noted that the operational amplifier U7 is mainly used to amplify the input signal and compare it with the feedback signal. Its input receives the electric guitar analog audio signal (from the output of operational amplifier U1), the positive feedback signal (from the output of operational amplifier U3), and the reverse feedback signal (from the output of operational amplifier U4). The output of operational amplifier U7 generates an adjustment signal according to the comparison result of the input signal, and this signal is used to adjust the amplitude limiting processing of the subsequent circuit. Specifically, the working principle of operational amplifier U7 is as follows: it amplifies the difference between the electric guitar signal and the feedback signal to generate an adjustment signal. Based on this signal, operational amplifier U7 adjusts the amplitude limiting degree of the signal by controlling the working state of diodes D1 and D2. Diodes D1 and D2 are set inside operational amplifier U7, which can play the role of amplitude limiting protection and signal adjustment. Specifically: when the voltage of the signal exceeds a certain threshold, diode D1 will turn on, limit the current passing through, ensure that the signal amplitude will not increase infinitely, and avoid distortion caused by excessive signals. Similar to diode D1, diode D2 is used to process reverse signals, limit the amplitude of negative signals, and ensure that the signal is controlled in both positive and negative directions. The configuration of diodes D1 and D2 can provide bidirectional limiting protection, that is, limiting the signals in the forward and reverse directions to ensure that the signals do not exceed the set range. Resistors R1 and R2 help set the gain of the signal and the adjustment of the input signal, affecting the amplification process of the signal in the operational amplifier U7. Specifically, R1 and R2 can form a voltage divider circuit to control the input and adjustment of the signal, thereby affecting the feedback loop of the operational amplifier U7. Resistor R3 works with diode D2 to help set the amplitude limit of the reverse signal. By controlling the current flowing through diode D2, resistor R3 and diode D2 jointly limit the strength of the reverse signal, which can avoid excessive reverse signals. Resistor R4 is connected to the output end of the operational amplifier U7 and is used to set the output of the limiting adjustment signal.The operational amplifier U7 outputs a limit adjustment signal according to the comparison result between the input signal and the feedback signal. This signal will be sent to the downstream circuit to dynamically adjust the working state of the limit protection circuit to ensure that the amplitude of the signal remains within an appropriate range. The operational amplifier U7 generates a control signal by comparing the amplitude of the electric guitar signal and the feedback signal, which is used to control the action of the limit circuit. If the amplitude of the input signal is too large, the limit adjustment signal will prompt the limit protection circuit to reduce the amplitude of the signal to avoid signal overload and distortion. In general, the main function of the comparison adjustment circuit in this embodiment is to compare the electric guitar analog audio signal and the feedback signal, and generate a limit adjustment signal through the operational amplifier U7 to control the limit protection mechanism in the subsequent circuit. Diodes D1 and D2 provide a bidirectional limit function to ensure that the signal does not exceed the predetermined amplitude in both the positive and negative directions. Resistors R1, R2, R3 and R4 accurately control the signal adjustment process by setting gain and feedback, and finally ensure that the processing of the electric guitar signal in the circuit is always kept within an appropriate range through the output limit adjustment signal, avoiding distortion and overload, while optimizing the sound quality.

[0034] In some other embodiments, the power amplifier driving unit includes an operational amplifier U5 and an operational amplifier U6; the input end of the operational amplifier U5 is electrically connected to the limit adjustment signal output end of the feedback comparison and signal adjustment unit circuit, the output end of the operational amplifier U5 is an output end of the power amplifier driving unit circuit, the output end of the operational amplifier U5 is also connected to the input end of the operational amplifier U6, and the output end of the operational amplifier U6 is another output end of the power amplifier driving unit circuit; the operational amplifier U5 and the operational amplifier U6 generate positive and negative drive signal outputs according to the limit adjustment signal. It should be noted that the input end of the operational amplifier U5 is connected to the limit adjustment signal output end of the feedback comparison and signal adjustment unit circuit. This limit adjustment signal is generated through a feedback loop, the purpose of which is to dynamically adjust according to the amplitude of the input signal to ensure that the power amplifier will not be clipped or distorted due to excessive input signal. After receiving the limit adjustment signal, the operational amplifier U5 will generate a positive drive signal output according to the signal. This signal is sent to an output end of the power amplifier driving unit. The output end of the operational amplifier U5 is also connected to the input end of the operational amplifier U6, which means that the output signal of U5 will directly affect the working state of U6. After receiving the output signal of U5, the operational amplifier U6 generates a reverse drive signal output based on the same limit adjustment signal. This reverse drive signal interacts with the forward drive signal to help form a differential signal output, and finally realizes the efficient drive of the power amplifier. Through the operation of the operational amplifiers U6 and U5, forward and reverse drive signals are finally generated, and these signals are sent to the power amplifier output unit circuit. The power amplifier output unit circuit performs differential amplification on these drive signals to obtain an electric guitar music signal for access to a speaker. In this embodiment, since the signals of the operational amplifiers U6 and U5 cooperate with each other, and their operation is controlled by the limit adjustment signal, the output drive signal can be dynamically adjusted according to the amplitude of the input signal, effectively avoiding the overload, clipping or distortion of the power amplifier caused by excessive fluctuations in the input signal, thereby ensuring the quality and stability of signal amplification.

[0035] In some other embodiments, the power amplifier output unit circuit includes a Poweramp chip and an SMPS circuit electrically connected to the Poweramp chip; the two input ends of the Poweramp chip are connected to the output ends of the operational amplifier U5 and the operational amplifier U6, and the Poweramp chip is used to differentially amplify the forward and reverse drive signals after receiving the forward and reverse drive signals to obtain an electric guitar music signal for access to the speaker for playback. It should be noted that the two input ends of the Poweramp chip are respectively connected to the output ends of the operational amplifiers U5 and U6, and the forward and reverse drive signals generated by the power amplifier drive unit are sent to the input end of the Poweramp chip. After receiving the forward and reverse drive signals, the Poweramp chip performs differential amplification. Differential amplification refers to the chip comparing and amplifying two input signals (forward and reverse) to obtain an amplified difference signal. This differential amplification process helps to enhance the strength of the signal, and by combining the signals of the two poles, maintains the accuracy and integrity of the signal and avoids signal distortion. After the differential amplification is completed, the Poweramp chip outputs a high-power electric guitar music signal, which has sufficient strength and quality and can be directly connected to the speaker for playback. The SMPS circuit (switching power supply module) is responsible for providing a stable and efficient voltage to the Poweramp chip. The SMPS circuit converts the input DC power supply (such as 12V or 24V) into a high voltage (such as ±15V or higher) suitable for the Poweramp chip to work through an efficient conversion method. Compared with linear power supplies, SMPS circuits can provide greater power output at lower power loss. The SMPS circuit works in a switching manner and can effectively adjust the power supply voltage to ensure that the Poweramp chip obtains a stable power supply and avoids distortion or unstable output caused by voltage fluctuations. The Poweramp chip is a power amplifier chip that can be used to amplify low-level audio signals to a level sufficient to drive the speakers.

[0036] In some further embodiments, when the Poweramp chip performs differential amplification on the received forward and reverse drive signals, the method includes: performing real-time amplitude detection on the forward drive signal and the reverse drive signal input to the Poweramp chip, and using an adaptive algorithm to perform adaptive gain adjustment on the forward drive signal and the reverse drive signal according to the amplitude changes of the forward drive signal and the reverse drive signal, and reducing the gain when the amplitude of the drive signal input to the Poweramp chip exceeds a preset threshold; increasing the gain when the amplitude of the drive signal input to the Poweramp chip is lower than the preset threshold; performing differential calculation on the forward drive signal and the reverse drive signal after adaptive gain adjustment to obtain an initial differential signal, and performing low-pass filtering on the initial differential signal to obtain a filtered differential signal; performing real-time distortion detection on the filtered differential signal to determine whether the filtered differential signal enters a nonlinear interval; if a distorted signal is detected, dynamically adjusting the gain of the filtered differential signal through a gain callback mechanism, and repairing the signal waveform of the differential signal that still has nonlinear distortion after the dynamic adjustment of the gain callback mechanism through a nonlinear distortion compensation algorithm, so as to obtain an electric guitar music signal for connecting to a speaker for playback. It should be noted that, in this embodiment, the forward and reverse drive signals received by the Poweramp chip from the operational amplifiers U5 and U6 may cause signal fluctuations due to changes in the input amplitude. After receiving the forward and reverse drive signals, the chip monitors the amplitudes of the two signals in real time and determines whether they exceed the preset threshold range. According to the real-time amplitude change, the Poweramp chip uses an adaptive algorithm to adjust the gain. If the signal amplitude exceeds the preset threshold, the gain is reduced to avoid overload; if the signal amplitude is low, the gain is increased to maintain a suitable amplification level, further preventing signal clipping or loss. In addition, the forward and reverse drive signals after adaptive gain adjustment are differentially calculated to ensure that the difference between the positive and reverse signals is effectively amplified, eliminate the noise generated by the common mode signal, and obtain the initial differential signal. The obtained initial differential signal will be processed by low-pass filtering to filter out high-frequency noise, reduce interference, and ensure the purity and stability of the signal. The filtered signal can avoid sound quality problems caused by noise during the power amplification process. After the filtered differential signal is amplified, the Poweramp chip detects in real time whether the signal enters the nonlinear interval (i.e., the distortion interval). Distortion detection can be judged by monitoring the waveform changes of the output signal. If the signal is found to have obvious nonlinear distortion, the gain adjustment mechanism will be triggered. If signal distortion is detected, the chip will dynamically adjust the gain through the gain callback mechanism to avoid excessive amplitude causing further distortion of the signal, thereby reducing the risk of signal overload and ensuring the clarity of sound quality by accurately controlling the gain adjustment.After the gain is adjusted back, the signal waveform may still have some slight distortion. In order to further optimize the output sound quality, the Poweramp chip repairs the signal through a nonlinear distortion compensation algorithm. The nonlinear distortion compensation algorithm corrects the signal according to the detected distortion characteristics, restores its original waveform, and makes the signal smoother and more realistic. The final signal after gain adjustment and distortion compensation is used as a high-fidelity electric guitar music signal for input into the speaker system for playback. It can be understood that in this embodiment, the adaptive gain adjustment can ensure that the circuit can adjust the gain in real time when the input signal strength changes to prevent the signal amplitude from being too large or too small. This dynamic response helps to process input signals from different guitar players or environments, ensure the stable operation of the power amplifier module circuit, and avoid clipping distortion. Through differential calculation and low-pass filtering, the noise and interference of the signal are effectively filtered, especially the common mode noise is eliminated, thereby reducing unnecessary signal pollution. In addition, the distortion detection and gain adjustment technology can monitor in real time whether the signal enters the distortion zone, dynamically adjust the gain, and effectively avoid distortion problems such as signal overload and clipping. Combined with the nonlinear distortion compensation algorithm, it can repair slight distortion and further improve the quality and stability of the output signal. Among them, Poweramp chip refers to the power amplifier chip.

[0037] Further, when repairing the signal waveform of the differential signal that still has nonlinear distortion by the nonlinear distortion compensation algorithm, it can include: real-time sampling of the signal waveform of the differential signal after the gain callback mechanism is dynamically adjusted to obtain the instantaneous amplitude and waveform of the differential signal; calculating the instantaneous amplitude and waveform of the acquired differential signal to determine whether the differential signal after the gain callback mechanism is dynamically adjusted exceeds a preset threshold, if it exceeds, it is determined that the differential signal after the gain callback mechanism is dynamically adjusted still has nonlinear distortion, and the gain adjustment factor is calculated for the differential signal that still has nonlinear distortion, and the gain adjustment factor is calculated by the following formula:

[0038] ;

[0039] In the formula, is the gain adjustment factor, is the gain adjustment coefficient, is the instantaneous amplitude of the differential signal, is the nonlinear coefficient that controls the distortion intensity, is the absolute value of the instantaneous amplitude of the differential signal, is the time variable;

[0040] Based on the gain adjustment factor, the signal amplitude of the differential signal that still has nonlinear distortion is gain adjusted to obtain a gain-adjusted signal, so that the signal amplitude of the differential signal that still has nonlinear distortion is restored to a linear range, and a polynomial fitting is performed on the gain-adjusted signal to smooth the waveform generated by the nonlinear distortion, and a repaired differential signal is obtained as an electric guitar music signal for connecting to a speaker for playback; the polynomial fitting formula is:

[0041] ;

[0042] is the repaired differential signal, is the gain-adjusted signal, is the fitting coefficient, The degree of the polynomial.

[0043] It should be noted that, in this embodiment, by calculating the instantaneous amplitude, it is determined whether the signal enters the nonlinear distortion area. When the signal amplitude exceeds the preset threshold, the compensation algorithm is triggered to repair the distortion. The gain adjustment factor is dynamically calculated by a formula, and the factor adjusts the signal gain according to the instantaneous amplitude of the signal to prevent the signal from being further distorted. The nonlinear characteristics of the gain adjustment can effectively reduce the distortion of the signal and restore the linearity of the signal. The signal is repaired by a polynomial fitting method to remove the sharp changes in the waveform caused by nonlinear distortion. Polynomial fitting can smooth the signal waveform to ensure the clarity and stability of the signal. It can be understood that in this embodiment, by detecting the distortion in real time and dynamically adjusting the gain, the nonlinear distortion in the input signal of the Poweramp chip can be effectively suppressed, and the signal can be restored to the linear range by the gain adjustment factor. Through polynomial fitting, the waveform distortion caused by nonlinear distortion can be repaired to ensure the high-quality output of the signal, which is suitable for the precise amplification and transmission of high dynamic range audio signals such as electric guitars.

[0044] It should be pointed out that the above embodiments are only preferred specific implementations of the present invention, rather than limiting them. The protection scope of the present invention is not limited thereto. The technical features in the above embodiments or different embodiments can also be combined, and there are many other changes in different aspects of the present invention as described above. The technical solutions recorded in the above embodiments can still be modified, or some of the technical features can be replaced by equivalents; and these modifications or replacements do not make the essence of the corresponding technical solutions deviate from the scope of the technical solutions of the embodiments of the present invention. Any changes or replacements that can be easily thought of by any technician familiar with the technical field within the technical scope disclosed by the present invention should be covered within the protection scope of the present invention, and the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A power amplifier module circuit for a mixing console, characterized in that: include: The buffer amplifier unit circuit is used to receive the real-time input electric guitar signal, buffer it and amplify it, so as to obtain an electric guitar analog audio signal output that is in phase and frequency with the input electric guitar signal and has an amplified amplitude; A limiting protection circuit is electrically connected to the output end of the buffer amplifier unit circuit, and is used for receiving the electric guitar analog audio signal and performing limiting processing to obtain a limited electric guitar analog audio signal; A feedback comparison and signal adjustment unit circuit is electrically connected to the output end of the amplitude limiting protection circuit, and is used to receive the amplitude limited electric guitar analog audio signal and perform positive and reverse processing to obtain positive and reverse feedback signals, and compare the positive and reverse feedback signals with the electric guitar analog audio signal obtained by buffering and amplifying the buffer amplifier unit circuit, and then output an amplitude limiting adjustment signal; A power amplification driving unit circuit, electrically connected to the limit adjustment signal output terminal of the feedback comparison and signal adjustment unit circuit, and used for generating positive and reverse driving signal outputs according to the limit adjustment signal; The power amplifier output unit circuit is electrically connected to the output end of the power amplifier driving unit circuit, and is used to receive the positive and reverse driving signals and then differentially amplify the positive and reverse driving signals to obtain an electric guitar music signal for connecting to a speaker for playing.

2. The power amplifier module circuit of the mixing console as claimed in claim 1, characterized in that: Also includes: An output filter unit circuit is connected to the power amplifier output unit circuit to obtain the electric guitar music signal; before the electric guitar music signal is input into the speaker for playing, the output filter unit circuit filters the electric guitar music signal to filter out high-frequency noise in the electric guitar music signal.

3. The power amplifier module circuit of the mixing console as claimed in claim 2, characterized in that: It also includes an audio interface, which is connected to the output end of the output filter unit circuit to connect the electric guitar music signal after high-frequency noise is filtered out to a speaker for playback.

4. The power amplifier module circuit of the mixing console as claimed in claim 3, characterized in that: The buffer amplifier unit circuit includes an operational amplifier U1, and the signal input end of the operational amplifier U1 receives the real-time input electric guitar signal Input for buffering and amplification to obtain an electric guitar analog audio signal output that is in phase, has the same frequency and has an amplified amplitude as the input electric guitar signal Input.

5. The power amplifier module circuit of the mixing console as claimed in claim 4, characterized in that: The limiting protection circuit includes a gain amplifier circuit and a limiting protection circuit; the input end of the gain amplifier circuit is electrically connected to the output end of the electric guitar analog audio signal of the operational amplifier U1, and is used to receive the electric guitar analog audio signal and then perform gain amplification; the output end of the gain amplifier circuit is electrically connected to the input end of the limiting protection circuit, and the limiting protection circuit receives the electric guitar analog audio signal after gain amplification and then performs limiting protection processing to obtain the output of the limited electric guitar analog audio signal.

6. The power amplifier module circuit of the mixing console as claimed in claim 5, characterized in that: The gain amplifier circuit includes an operational amplifier U2; the input end of the operational amplifier U2 is the input end of the gain amplifier circuit, and the output end of the operational amplifier U2 is the output end of the gain amplifier circuit.

7. The power amplifier module circuit of the mixing console as claimed in claim 6, characterized in that: The limiting protection circuit includes a diode group D3 with anodes and cathodes connected in series; the series ends of two diodes in the diode group D3 with anodes and cathodes connected in series are the input ends of the limiting protection circuit, the non-series cathode of one diode in the diode group D3 with anodes and cathodes connected in series is the first output end of the limiting protection circuit that outputs the electric guitar simulated audio signal after limiting, and the non-series anode of one diode in the diode group D3 with anodes and cathodes connected in series is the second output end of the limiting protection circuit that outputs the electric guitar simulated audio signal after limiting.

8. The power amplifier module circuit of the mixing console as claimed in claim 7, characterized in that: The feedback comparison and signal adjustment unit circuit includes a feedback signal generation circuit and a comparison adjustment circuit; the feedback signal generation circuit is electrically connected to the output end of the limit protection circuit, and is used to receive the electric guitar analog audio signal after the limit, and then perform positive and reverse processing to obtain positive and reverse feedback signals and output them to the comparison adjustment circuit; The comparison signal input terminal of the comparison adjustment circuit is electrically connected to the output terminal of the electric guitar analog audio signal of the operational amplifier U1 and the output terminal of the feedback signal generating circuit that outputs the positive and negative feedback signals, and is used to compare the received positive and negative feedback signals with the electric guitar analog audio signal and output a limiting adjustment signal.

9. The power amplifier module circuit of the mixing console as claimed in claim 8, characterized in that: The feedback signal generating circuit includes an operational amplifier U3 and an operational amplifier U4; the non-inverting end of the operational amplifier U3 is the first receiving end for receiving the electric guitar simulated audio signal after limiting, the inverting end of the operational amplifier U3 is connected to the non-inverting end of the operational amplifier U4, and the inverting end of the operational amplifier U4 is the second receiving end for receiving the electric guitar simulated audio signal after limiting; the output ends of the operational amplifier U3 and the operational amplifier U4 output the positive and negative feedback signals to the comparison and adjustment circuit.

10. The power amplifier module circuit of the mixing console as claimed in claim 9, characterized in that: The comparison and adjustment circuit includes an operational amplifier U7, a diode D1, a diode D2, a resistor R1, a resistor R2, a resistor R3 and a resistor R4; the input end of the operational amplifier U7 is the comparison signal input end of the comparison and adjustment circuit, which is connected to the output end of the electric guitar simulated audio signal of the operational amplifier U1 and the output ends of the operational amplifier U3 and the operational amplifier U4 that output the positive and negative feedback signals; the diode D1 and the diode D2 are arranged inside the operational amplifier U7, the anodes of the diode D1 and the diode D2 are commonly connected to one end of the resistor R2, and the other end of the resistor R2 is grounded; the cathode of the diode D1 is connected to the inverting end of the operational amplifier U7, one end of the resistor R1 and one end of the resistor R4, the other end of the resistor R1 is grounded, and the other end of the resistor R4 is the output end of the comparison and adjustment circuit that outputs the limiting adjustment signal; the cathode of the diode D2 is connected to the in-phase end of the operational amplifier U7 and one end of the resistor R3, and the other end of the resistor R3 is grounded.

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