Pre-amplifier module circuit of sound console

Abstract

The invention relates to the technical field of amplification control and the like, and provides a pre-amplifier module circuit of a sound console, an input processing circuit of the module circuit buffers and amplifies an electric guitar signal to obtain a standard-level electric guitar signal, and outputs the standard-level electric guitar signal to a limiting circuit of the module circuit for processing; the fidelity electric guitar signal is adjusted by a sound effect adjusting circuit of the module circuit, and a preliminary sound mixing electric guitar signal is output to an attenuation circuit of the module circuit for processing, so that an effector input signal is obtained and is transmitted to an external effector for processing to generate a to-be-mixed electric guitar signal; the AUX interface audio signal processing circuit of the module circuit accesses an AUX interface audio signal and then processes the AUX interface audio signal to obtain a to-be-mixed audio signal, and the sound mixing signal output processing circuit of the module circuit processes the to-be-mixed audio signal and a to-be-mixed electric guitar signal to obtain a sound mixing signal suitable for earphone playing for output. Therefore, the audios of different signal sources can be ensured to work seamlessly and coordinately, and the audio output quality is improved.

Description

Technical Field

[0001] The 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 preamplifier module circuit of a mixing console. Background Art

[0002] The mixer preamplifier module is a key component in mixer technology. It can be used to amplify the gain, adjust the sound effects, mix the signals and finally output the electric guitar signal. The mixer preamplifier circuit needs to meet multiple requirements, including high fidelity, low noise, adaptability to the level of different signal sources, flexible sound effect adjustment, etc. However, in the prior art, the mixer preamplifier module has some significant technical defects in achieving these functions. For example, in the traditional mixer design, the signal levels from different audio sources (such as electric guitar and AUX input) are quite different, which leads to problems when mixing signals. Electric guitar signals are usually weak and low in level, requiring higher gain amplification; while AUX interface audio signals usually come from external audio devices and have higher levels. Due to the lack of sufficient gain adjustment and level matching means, the two signals may have inconsistent levels when mixed, resulting in some signals being too strong and some signals being too weak during audio output, or even distortion or signal loss. For example, the signal processing circuit of the mixer preamplifier module may not fully consider the isolation between signal sources. In particular, different audio sources from AUX input and electric guitar signals may interfere with each other without effective isolation, resulting in signal crosstalk and increased noise. This crosstalk phenomenon not only affects the audio quality, but may also cause audio distortion and reduce the signal-to-noise ratio of the system. For another example, AUX interface audio signals usually come from different audio devices, such as audio players, external effectors, etc. Since the signal level and impedance characteristics of these devices are different from those of electric guitar signals, the mixer lacks effective circuits to properly amplify, gain adjust, and impedance match the AUX interface audio signals. As a result, the AUX interface audio signal may not be able to work in harmony with the electric guitar signal, resulting in problems such as unbalanced volume and reduced audio quality during mixing. For another example, electric guitar signals usually need to be processed through effects, with sound effects such as distortion, reverberation, and delay; while AUX interface audio signals usually come from external devices, without processing or with fewer sound effects. In traditional mixers, the mixing and adjustment of audio effects may not be consistent across different signal sources, especially when processing AUX interface audio signals and electric guitar signals at the same time. This inharmonious nature of audio processing can result in unnatural audio mixing, lacking depth and space.

[0003] In summary, the existing mixer preamplifier module technology generally has problems such as level mismatch, insufficient signal isolation, and noise interference when facing electric guitar signals and AUX interface audio signals. In addition, the adaptation and processing of AUX interface audio signals and the unified adjustment of sound effects are often not effectively solved. Summary of the invention

[0004] The present invention provides a preamplifier module circuit for a mixing console, which aims to ensure that audios from different signal sources can work seamlessly and harmoniously through precise signal gain adjustment, signal isolation, mixing processing and the like, improve the audio output quality, and ensure that high-quality audio processing and mixing effects can be achieved under different sound sources.

[0005] The present invention provides a preamplifier module circuit of a mixing console, comprising: The electric guitar signal input processing circuit is used to receive the electric guitar signal for buffering and to amplify the buffered electric guitar signal to obtain a standard level electric guitar signal output after the level is increased; A limiting circuit, electrically connected to the output end of the electric guitar signal input processing circuit, for performing level limiting processing after receiving the standard level electric guitar signal, so as to obtain a fidelity electric guitar signal output whose level does not exceed a first threshold range; A sound effect adjustment circuit is electrically connected to the output end of the limiting circuit and is used to perform sound effect adjustment after receiving the fidelity electric guitar signal to obtain a preliminary mixed electric guitar signal output adapted for mixing processing; an attenuation circuit, electrically connected to the output end of the sound effect adjustment circuit, for receiving the preliminary mixed electric guitar signal and then performing level attenuation processing to obtain an effector input signal whose level does not exceed the second threshold range and transmit it to an external effector, wherein the external effector further performs sound effect adjustment on the effector input signal to obtain an electric guitar signal to be mixed that is adapted for mixing processing; An AUX interface audio signal processing circuit is used to receive the AUX interface audio signal and then amplify it to obtain an audio signal to be mixed whose level matches that of the electric guitar signal to be mixed; The mixed signal output processing circuit is electrically connected to the output end of the external effector and the AUX interface audio signal processing circuit, and is used for receiving the audio signal to be mixed and the electric guitar signal to be mixed, and then adjusting the mixing gain to obtain a mixed signal with a moderate volume, and performing headphone amplifier processing on the mixed signal with a moderate volume to obtain a mixed signal suitable for headphone playback for output to the headphone.

[0006] Compared with the prior art, the present invention has the following beneficial effects: The present invention provides a preamplifier module circuit of a mixing console. The preamplifier module circuit comprises an electric guitar signal input processing circuit, a limiting circuit, a sound effect adjustment circuit, an attenuation circuit, an AUX interface audio signal processing circuit and a mixed signal output processing circuit. The electric guitar signal input processing circuit is used for receiving an electric guitar signal for buffering processing, and performing gain amplification on the buffered electric guitar signal to obtain a standard level electric guitar signal output after the level is increased. The limiting circuit is electrically connected to the output end of the electric guitar signal input processing circuit and is used for performing level limiting processing after receiving the standard level electric guitar signal to obtain a fidelity electric guitar signal output whose level does not exceed a first threshold range. The sound effect adjustment circuit is electrically connected to the output end of the limiting circuit and is used for performing sound effect adjustment after receiving the fidelity electric guitar signal to obtain a preliminary mixed electric guitar signal output adapted for mixing processing. The attenuation circuit is electrically connected to the output end of the sound effect adjustment circuit and is used for performing level attenuation processing after receiving the preliminary mixed electric guitar signal to obtain a fidelity electric guitar signal output adapted for mixing processing. The effector input signal whose level does not exceed the second threshold range is transmitted to the external effector, and the external effector further adjusts the sound effect of the effector input signal to obtain an electric guitar signal output to be mixed that is adapted for mixing processing. The AUX interface audio signal processing circuit is used to receive the AUX interface audio signal and then perform amplification processing to obtain an audio signal output to be mixed whose level matches the electric guitar signal to be mixed. The mixed signal output processing circuit is electrically connected to the output end of the external effector and the AUX interface audio signal processing circuit, and is used to receive the audio signal to be mixed and the electric guitar signal to be mixed and then perform mixing gain adjustment to obtain a mixed signal with a moderate volume, and perform headphone amplifier processing on the mixed signal with a moderate volume to obtain a mixed signal suitable for headphone playback for output to the headphone, thereby ensuring that the audio of different signal sources can work seamlessly in coordination, improving the audio output quality, and ensuring that high-quality audio processing and mixing effects can be achieved under different sound sources. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] 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: Figure 1 It is a circuit structure schematic diagram of a preamplifier module circuit of a mixer according to an embodiment of the present invention; Figure 2 It is a circuit structure diagram of a preamplifier module circuit of a mixing console connected to an external effector according to an embodiment of the present invention; Figure 3 The present invention is a schematic diagram of a circuit structure in which a preamplifier module circuit of a mixing console is connected to headphones.

[0008] Description of reference numerals: 100, electric guitar signal input processing circuit; 200, limiting circuit; 300, sound effect adjustment circuit; 400, attenuation circuit; 500, AUX interface audio signal processing circuit; 600, mixing signal output processing circuit; 700, external effector; 800, headphones. DETAILED DESCRIPTION

[0009] 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.

[0010] See also Figure 1-Figure 3 , an embodiment of the present invention provides a preamplifier module circuit of a mixing console, comprising: The electric guitar signal input processing circuit is used to receive the electric guitar signal for buffering and to amplify the buffered electric guitar signal to obtain a standard level electric guitar signal output after the level is increased; A limiting circuit, electrically connected to the output end of the electric guitar signal input processing circuit, for performing level limiting processing after receiving the standard level electric guitar signal, so as to obtain a fidelity electric guitar signal output whose level does not exceed a first threshold range; A sound effect adjustment circuit is electrically connected to the output end of the limiting circuit and is used to perform sound effect adjustment after receiving the fidelity electric guitar signal to obtain a preliminary mixed electric guitar signal output adapted for mixing processing; an attenuation circuit, electrically connected to the output end of the sound effect adjustment circuit, for receiving the preliminary mixed electric guitar signal and then performing level attenuation processing to obtain an effector input signal whose level does not exceed the second threshold range and transmit it to an external effector, wherein the external effector further performs sound effect adjustment on the effector input signal to obtain an electric guitar signal to be mixed that is adapted for mixing processing; An AUX interface audio signal processing circuit is used to receive the AUX interface audio signal and then amplify it to obtain an audio signal to be mixed whose level matches that of the electric guitar signal to be mixed; The mixed signal output processing circuit is electrically connected to the output end of the external effector and the AUX interface audio signal processing circuit, and is used for receiving the audio signal to be mixed and the electric guitar signal to be mixed, and then adjusting the mixing gain to obtain a mixed signal with a moderate volume, and performing headphone amplifier processing on the mixed signal with a moderate volume to obtain a mixed signal suitable for headphone playback for output to the headphone.

[0011] It should be noted that the electric guitar signal is usually at a low level and needs to be buffered and gain-amplified. In this embodiment, after the electric guitar signal is buffered and gain-amplified by the electric guitar signal input processing circuit, the level of the electric guitar signal can be improved to reach the standard level range, which is convenient for subsequent limiting circuit processing. The limiting circuit is used to limit the maximum level of the standard level electric guitar signal to avoid distortion caused by excessive signal strength. The limiting circuit sets a first threshold range, and any standard level electric guitar signal exceeding this first threshold range will be compressed or limited to obtain a fidelity electric guitar signal output, ensuring that the dynamic range of the output signal is within an appropriate range, and ensuring the clarity and fidelity of the sound quality. The sound effect adjustment circuit performs sound effect processing and frequency response adjustment on the fidelity electric guitar signal. By adjusting the sound effect (such as high-frequency enhancement, low-frequency attenuation, etc.), the fidelity electric guitar signal is adapted to the mixing requirements, ensuring the sound quality adjustment of the fidelity electric guitar signal, making it more in line with the overall sound effect requirements of the mixing console, and obtaining a preliminary mixed electric guitar signal. The preliminary mixed electric guitar signal output from the sound effect adjustment circuit is attenuated by the attenuation circuit. The function of the attenuation circuit is to reduce the level of the preliminary mixed electric guitar signal to a level suitable for being sent to the external effector, so as to prevent the external effector from being distorted due to an excessively strong input signal. The attenuation circuit adjusts the level of the preliminary mixed electric guitar signal to a suitable range to ensure that the subsequent processing of the external effector will not cause distortion or degradation of the sound quality. The attenuated preliminary mixed electric guitar signal is output to the external effector for further sound effect processing (such as distortion, reverberation, delay, etc.). The external effector adjusts the sound effect of the attenuated preliminary mixed electric guitar signal to obtain an electric guitar signal to be mixed suitable for mixing with other audio signals. The AUX interface audio signal processing circuit is connected to the AUX interface audio signal, and the AUX interface audio signal is a signal of an external audio device (such as an audio player, etc.). The AUX interface audio signal usually has a high level and needs to be processed by gain amplification to match it with the electric guitar signal to be mixed to obtain the audio signal to be mixed. The AUX interface audio signal is adjusted by gain to obtain the audio signal to be mixed. The levels of the audio signal to be mixed and the electric guitar signal to be mixed can be adapted to facilitate the coordinated work of the subsequent mixed signal output processing circuit. The audio signal to be mixed and the electric guitar signal to be mixed enter the mixed signal output processing circuit together. The mixed signal output processing circuit performs mixing gain adjustment on the audio signal to be mixed and the electric guitar signal to be mixed to ensure that the volume of the mixed signal is moderate and obtain a mixed signal with moderate volume. Finally, the mixed signal with moderate volume is processed by the headphone amplifier to obtain a mixed signal suitable for headphone playback for output to the headphone, ensuring that the final volume is suitable for headphone playback and maintaining the sound quality without distortion. It should be noted that in this embodiment, the first threshold range can be set to the maximum safe level of the signal before entering the subsequent processing stage. This range is used to avoid distortion caused by excessive input signals. For the electric guitar signal input processing circuit, this threshold range can be designed according to the signal source and the required sound quality.For example: Assuming that the working level range of a standard electric guitar signal is between 0.1V and 1V, the first threshold range can be set to 0.5V to 1.5V, which can ensure that the signal remains clear and prevents overload caused by exceeding the maximum safe level. The second threshold range can be used to limit the input signal of the effector, ensuring that the signal level transmitted to the external effector is not too high or too low, which affects the subsequent sound effect processing. The second threshold range can be set to adapt to the maximum input level of the external effector and mixing processing. For example: Assuming that the ideal range of the effector input signal is -10dB to +4dB, the second threshold range can be set to this range to ensure that the signal is not too strong to cause excessive distortion of the external effector, or too weak to cause the effector to fail to perform at its maximum performance. In summary, the first threshold range is mainly used to ensure that the signal after entering the electric guitar input processing circuit is not too strong, thereby avoiding damage to the circuit or distortion; the second threshold range is mainly used to ensure that the signal transmitted to the external effector is suitable for further sound effect processing, ensuring the best performance of the sound effector.

[0012] In some preferred embodiments, the electric guitar signal input processing circuit includes an input buffer circuit and a gain amplifier circuit, and the output end of the input buffer circuit is electrically connected to the input end of the gain amplifier circuit; after the input end of the input buffer circuit is connected to the electric guitar signal, the input buffer circuit performs buffer processing on the connected electric guitar signal to obtain a buffered electric guitar signal and outputs it to the gain amplifier circuit, and the gain amplifier circuit performs gain amplification on the buffered electric guitar signal to obtain a standard level electric guitar signal output after the level is increased. It should be noted that the electric guitar signal is usually connected to the mixer preamplifier module circuit through the input end from an external device (such as an electric guitar). Since the electric guitar signal is usually at a low level (weak signal), it may be interfered, distorted or attenuated if it directly enters the subsequent circuit. Therefore, the role of the input buffer circuit is very critical. After the input end of the input buffer circuit is connected to the electric guitar signal, the input buffer circuit can buffer the connected electric guitar signal. The input buffer circuit can adopt a circuit structure with high input impedance, which will not burden the electric guitar signal, nor consume the energy of the signal, and ensure the integrity of the signal source. After buffering, the electric guitar signal maintains its integrity and is not affected by the input impedance, thereby ensuring the quality and stability of the signal. The buffered electric guitar signal passes through the gain amplifier circuit. Through appropriate gain settings, the gain amplifier circuit can amplify the electric guitar signal to a standard level range suitable for subsequent processing and mixing. This gain amplification process can not only ensure that the level of the electric guitar signal reaches the ideal range, but also ensure that the signal can be transmitted to subsequent circuits (such as limiting circuits, sound effect adjustment circuits, etc.) without signal loss or insufficiency. The gain amplifier circuit increases the signal to a standard level output, so that the subsequent circuit can process the signal losslessly and clearly. Through reasonable gain settings, distortion and interference in the subsequent audio processing stage can be avoided. In this embodiment, through the design of the two stages of input buffering and gain amplification, the adaptability of the mixer preamplifier module to different signal sources can be enhanced, so that the circuit can automatically adjust the signal level and ensure the stability of the signal when facing different types of signal sources (such as electric guitars, AUX inputs, etc.), greatly improving the flexibility and stability of the mixer.

[0013] In some preferred embodiments, the input buffer circuit includes an operational amplifier U1. After the input end of the operational amplifier U1 is connected to the electric guitar signal, the operational amplifier U1 performs buffering processing on the connected electric guitar signal to obtain a buffered electric guitar signal and output it to the gain amplifier circuit. It should be noted that the high input impedance of the operational amplifier U1 at the input end can effectively prevent the impedance loading effect of the electric guitar signal source, thereby ensuring the integrity of the signal source output. In other words, the signal source will not produce obvious signal attenuation or distortion due to the access of the buffer circuit, and the signal remains pure and lossless. This is very important for electric guitar signals, because electric guitar signals are usually weak, and direct access to subsequent circuits is likely to cause signal attenuation and affect the sound quality. The operational amplifier U1 has a high input impedance, which enables it to receive signals from the electric guitar signal source without producing a significant load effect on the signal source. The electric guitar signal source can continue to work normally under a lower load.

[0014] In some preferred embodiments, the gain amplifier circuit includes an operational amplifier U2 and a variable resistor VR1; the input end of the operational amplifier U2 and the input end of the variable resistor VR1 are connected together to receive the buffered electric guitar signal; the output end of the operational amplifier U2 and the output end of the variable resistor VR1 are connected together to output the standard level electric guitar signal; the variable resistance adjustment end of the variable resistor VR1 is grounded; the operational amplifier U2 and the variable resistor VR1 jointly perform gain amplification processing on the buffered electric guitar signal to obtain a standard level electric guitar signal with an increased level. It should be noted that after the buffered electric guitar signal is output from the operational amplifier U1, it enters the gain amplifier circuit as an input signal. Specifically, the buffered signal is input to the input end of the operational amplifier U2 and also to the input end of the variable resistor VR1. The variable resistor VR1 is an adjustable resistor, and the gain can be controlled by adjusting its resistance value. The adjustment end of the variable resistor VR1 is grounded, and changing its resistance value will affect the gain of the operational amplifier U2, thereby affecting the gain amplification degree of the output signal. The adjustment end of the variable resistor VR1 is used to adjust the gain, so that the user can set the appropriate gain value as needed, thereby achieving accurate gain amplification of the electric guitar signal. The operational amplifier U2 is used for signal gain amplification. After receiving the buffered electric guitar signal, the operational amplifier U2 amplifies the input signal to an appropriate level in combination with the adjustment of the variable resistor VR1. The gain of the operational amplifier U2 can be determined by the resistance value of the variable resistor VR1. When the variable resistor is adjusted, it is equivalent to changing the feedback circuit of the operational amplifier, thereby adjusting the gain. Since the operational amplifier has high gain accuracy and stability, it can ensure that the output signal is increased to the required standard level without distortion. The gain-amplified signal is output through the output end of the operational amplifier U2 and the output end of the variable resistor VR1. At this time, the output signal has reached the required standard level and is suitable for subsequent circuit processing. The level of the output signal is precisely controlled to ensure that the signal will not be distorted or difficult to process due to excessively high or low levels in the subsequent processing stage.

[0015] In some preferred embodiments, the limiting circuit includes an operational amplifier U3, the input end of the operational amplifier U3 is connected to the output end of the operational amplifier U2 and the output end of the variable resistor VR1, and is used to receive the standard level electric guitar signal. The operational amplifier U3 performs level limiting processing on the received standard level electric guitar signal to obtain a fidelity electric guitar signal output whose level does not exceed the first threshold range. It should be noted that the electric guitar signal has been gain-amplified in the aforementioned gain amplifier circuit, and the standard level electric guitar signal enters the input end of the operational amplifier U3. The function of the operational amplifier U3 is to limit the level of the signal to ensure that the signal does not exceed the predetermined first threshold range. Once the signal level exceeds the first threshold range, the operational amplifier U3 can clamp the signal level within this threshold range to prevent the signal from being distorted or saturated due to excessively high levels. For audio signals, excessively high signal levels may cause distortion of the amplifier or overload of subsequent equipment, affecting the final sound quality. After the limiting processing of the operational amplifier U3, the output is a fidelity electric guitar signal whose level does not exceed the first threshold range. This signal will not exceed the set maximum level, so its sound quality is more stable and clear, and will not be distorted due to excessive level.

[0016] In some preferred embodiments, the sound effect adjustment circuit includes an equalizer EQ; the input end of the equalizer EQ is connected to the output end of the operational amplifier U3 for receiving the fidelity electric guitar signal; the equalizer EQ performs sound effect adjustment on the received fidelity electric guitar signal to obtain a preliminary mixed electric guitar signal output adapted for mixing processing. It should be noted that the electric guitar signal is processed by gain amplification, limitation, etc. to obtain a fidelity electric guitar signal. This signal has been level-limited by the operational amplifier U3 to ensure that its level is within a safe range. The fidelity electric guitar signal is transmitted to the equalizer EQ, that is, as the input signal of the equalizer EQ. The equalizer EQ is a circuit that can adjust the gain of signals in different frequency bands. It usually has multiple frequency bands, and can add or subtract gain to signals in different frequency bands such as low frequency, medium frequency, and high frequency, thereby adjusting the timbre or sound effect. In this embodiment, the equalizer EQ performs sound effect adjustment on the received fidelity electric guitar signal. This process can include bass enhancement, high frequency reduction, medium frequency correction, etc., and the timbre, dynamics, and spatial sense of the signal are changed by adjusting the gain of different frequency bands. After the sound effect is adjusted, the output is a preliminary mixed electric guitar signal adapted for mixing processing, which means that the sound quality of the signal has been optimized according to the adjustment requirements and is suitable for further mixing and processing. It can be understood that through the equalizer EQ, the sound effect of the electric guitar signal can be finely adjusted according to actual needs, such as increasing the weight of the low frequency, adjusting the mid-frequency to highlight certain timbres, or removing unnecessary frequencies. Through the equalizer EQ, the electric guitar signal can adapt to different music styles or performance requirements, providing flexible sound effect control.

[0017] Further, when the equalizer EQ adjusts the sound effect of the received fidelity electric guitar signal, it includes: independently adjusting different frequency bands of the received fidelity electric guitar signal through multiple filter segments (e.g., low frequency, intermediate frequency and high frequency) in the equalizer EQ, specifically: increasing the low frequency response of the low frequency band fidelity electric guitar signal (e.g., 20Hz-150Hz) to enhance the thickness of the electric guitar tone; strengthening the intermediate frequency response of the intermediate frequency band fidelity electric guitar signal (e.g., 150Hz-2kHz) to make the guitar tone clearer and more prominent; adjusting the high frequency part of the high frequency band fidelity electric guitar signal (e.g., 2kHz-10kHz) to enhance the clarity, brightness or sharpness of the guitar; dynamically adjusting the gain of different frequency bands of the independently adjusted fidelity electric guitar signal to obtain a preliminary mixed electric guitar signal output adapted for mixing processing. It should be noted that the low frequency is a very important part of the electric guitar tone, especially in styles such as heavy rock and blues, where the low frequency can provide a thick and deep sense of tone. The low-frequency component in the electric guitar signal affects the fullness and foundation of the sound quality. By increasing the low-frequency response, the sound of the electric guitar can better coordinate with low-frequency instruments such as bass guitar or drums in the mix, making the sound layered and richer. The mid-frequency is a key frequency band in the electric guitar sound, affecting the clarity and expressiveness of the notes. The characteristic sound of the electric guitar is usually located in the mid-frequency area, especially in the range below 2kHz. By enhancing the mid-frequency band, the performance of the guitar notes can be made more vivid and clear, especially when playing techniques such as glissando and pitch bending, which can enhance the fineness and dynamics of its sound. High frequencies affect the brightness, clarity and sharpness of the sound. Appropriate high-frequency enhancement can make the electric guitar sound brighter, more transparent and more delicate. The high-frequency part of the electric guitar is very important when playing fast notes, percussion sound effects or playing clear single notes. By enhancing the high-frequency part, the guitar can be made brighter and more delicate in the mix, especially the high-frequency part can enhance the attack and presence of the notes. Dynamic gain adjustment is the management of signal amplitude changes over time, ensuring that each frequency band is dynamically adjusted according to the actual strength of the signal without distortion and avoiding overload. Dynamic gain control can optimize the signals of different frequency bands according to the actual situation, avoiding excessive enhancement or attenuation of any frequency band. It can provide smoother audio performance and avoid distortion caused by excessive gain. Through this dynamic adjustment, the balance and consistency of the entire audio signal can be guaranteed, while avoiding the phenomenon of volume imbalance between different frequency bands of the audio signal.

[0018] In some preferred embodiments, the attenuation circuit includes an operational amplifier U4, the input end of which is connected to the output end of the equalizer EQ, for receiving the preliminary mixed electric guitar signal; the operational amplifier U4 performs level attenuation processing on the received preliminary mixed electric guitar signal to obtain an effector input signal whose level does not exceed the second threshold range and transmit it to the external effector. It should be noted that in the previous circuit, the electric guitar signal has been processed by gain amplification, limiting circuit and sound effect adjustment. In particular, in the sound effect adjustment stage, the signal passes through the equalizer EQ and is output as a preliminary mixed electric guitar signal after sound effect adjustment. The preliminary mixed electric guitar signal is input to the input end of the operational amplifier U4 as the object of attenuation processing. The operational amplifier U4 attenuates the level of the signal, reduces the amplitude of the signal by gain adjustment, and makes the signal level not exceed the set second threshold range. This level range can ensure that the signal will not exceed the input processing capacity of the effector when entering the external effector, thereby avoiding distortion or clipping caused by excessive signal strength. The attenuated signal will be transmitted to the input end of the external effector. The effector can further process the signal according to the set sound effect parameters to generate an electric guitar signal to be mixed that is suitable for mixing. It should be noted that in the entire circuit, the first threshold range mentioned above means that after the signal is processed by the limiting circuit (i.e., the operational amplifier U3), the level of the electric guitar signal is limited to a value not exceeding a specific range to ensure that the signal is not too strong, overloaded or distorted. This processing can ensure the quality and stability of the signal. Within the first threshold range, the signal has been limited by the operational amplifier U3 to avoid the signal being too strong and maintain its fidelity. The function of the attenuation circuit (U4) is to further attenuate the signal level to ensure that the signal level is not too high before it is sent to the external effector, resulting in improper processing by the external effector or distortion. Therefore, the first threshold range can limit the maximum level of the signal to ensure signal stability, and the signal is adjusted by the second threshold range to ensure that the signal can adapt to the input requirements of the external effector to avoid the risk of level mismatch between the two. The signal is processed by the first threshold range limitation before the attenuation circuit and the second threshold range attenuation after the attenuation circuit, so as to achieve the level balance between the electric guitar signal and other input signals (such as the AUX interface audio signal), and ensure the volume coordination of different signal sources during mixing.

[0019] In some preferred embodiments, the output end of the operational amplifier U4 is connected to the input end of the external effector through the socket FX SEND to transmit the effector input signal to the external effector for processing; the output end of the external effector is connected to the input end of the mixing signal output processing circuit through the socket FX RETURN to transmit the electric guitar signal to be mixed to the mixing signal output processing circuit for processing. It should be noted that the signal processed by the attenuation circuit (operational amplifier U4), that is, the effector input signal, is output through the socket FX SEND and transmitted to the input end of the external effector. The external effector performs further sound effect processing (such as delay, reverberation, distortion, etc.) on the input electric guitar signal to generate the electric guitar signal to be mixed. The signal processed by the external effector is returned to the preamplifier module of the mixer through the socket FX RETURN. This signal is connected to the mixing signal output processing circuit through the socket FX RETURN and begins to enter the subsequent mixing processing process.

[0020] Further, after the effector input signal whose level does not exceed the second threshold range is input to the external effector, the external effector performs a delay effect on the effector input signal to simulate the reflection effect of the guitar, and adds a sense of space to the effector input signal after the delay effect processing to enhance the reverberation effect of the guitar, and performs an overload process on the effector input signal after the sense of space processing to enhance the timbre expression of the guitar. It should be noted that the equalizer EQ mainly changes the timbre of the electric guitar signal by adjusting different frequency bands of the signal (such as low frequency, medium frequency and high frequency) to achieve a preliminary sound effect suitable for mixing processing. EQ can enhance or reduce certain frequencies to change the thickness, clarity or brightness of the guitar sound. However, the role of the equalizer EQ is to adjust the frequency level, and it has limited shaping of the spatial sense, dynamic changes and expressiveness of the signal. The equalizer cannot directly add a sense of space, delay or reverberation effect to the signal, nor can it simulate the dynamic changes of the guitar in actual performance (such as overload, etc.). The external effector can perform dynamic processing and spatial processing to provide a more delicate and rich expression for the signal. The delay effect simulates the reflection effect of the guitar, making the guitar notes reverberate after playing, enhancing the depth and spatial sense of the tone. Spatial processing (such as reverberation) adds a sense of environment to the signal, making the guitar tone more three-dimensional and layered, and enhancing the live performance of the guitar. Overload processing enhances the guitar's timbre expression, simulating the driving effect of the amplifier, making the tone more rough, powerful or aggressive. These effects cannot be achieved by the equalizer EQ, and they can bring stronger expressiveness, spatial sense and emotional expression to the electric guitar signal in practical applications. It can be seen that the electric guitar signal adjusted by the equalizer EQ, although it has been optimized and balanced at the frequency level, still has deficiencies in expressiveness, spatial sense, dynamic effect and emotional expression. The external effector further enhances the layering, spatial sense and expressiveness of the sound effect by adding effects such as delay and reverberation, making the guitar's tone richer, more moving and more expressive.

[0021] In some preferred embodiments, the AUX interface audio signal processing circuit includes an operational amplifier U5; after the input end of the operational amplifier U5 is connected to the AUX interface audio signal, the operational amplifier U5 amplifies the AUX interface audio signal to obtain an audio signal to be mixed whose level matches the electric guitar signal to be mixed; the output end of the operational amplifier U5 is connected to the mixed signal output processing circuit, and the audio signal to be mixed is output to the mixed signal output processing circuit for processing. It should be noted that the audio signal input through the AUX interface usually comes from an external device, such as an audio player. The output level of these devices is usually high, but different from the level of the electric guitar signal, so it needs to be processed to match other signals (such as the electric guitar signal). The operational amplifier U5 amplifies the input AUX interface audio signal. Specifically, the operational amplifier U5 adjusts the level of the AUX interface audio signal to a range that matches the electric guitar signal through gain adjustment. Since the level of the AUX interface audio signal is usually high, the operational amplifier U5 converts it into an audio signal to be mixed that matches the electric guitar signal through appropriate gain or attenuation to ensure consistent signal levels during mixing. The amplified audio signal to be mixed is transmitted to the mixed signal output processing circuit through the output end of the operational amplifier U5. This signal will enter the mixing stage together with the processed electric guitar signal for gain adjustment and sound effect processing, and finally form a mixed signal suitable for headphone playback.

[0022] In some preferred embodiments, the mixed signal output processing circuit includes a mixing gain adjustment circuit and a headphone amplifier processing circuit; the input end of the mixing gain adjustment circuit is electrically connected to the output end of the external effector and the output end of the AUX interface audio signal processing circuit, the output end of the mixing gain adjustment circuit is electrically connected to the input end of the headphone amplifier processing circuit, and the output end of the headphone amplifier processing circuit outputs the mixed signal suitable for headphone playback; the mixing gain adjustment circuit performs mixing gain adjustment on the received audio signal to be mixed and the electric guitar signal to be mixed to obtain a mixed signal with a moderate volume and output it to the headphone amplifier processing circuit, and the headphone amplifier processing circuit performs headphone amplifier processing on the mixed signal with a moderate volume to obtain the mixed signal suitable for headphone playback. It should be noted that the input end of the mixing gain adjustment circuit receives signals from the output end of the external effector and the output end of the AUX interface audio signal processing circuit. These signals include the processed electric guitar signal (i.e. the electric guitar signal to be mixed) and the amplified AUX interface audio signal (i.e. the audio signal to be mixed), which come from different audio sources (electric guitar and AUX interface device). After receiving the audio signals from two different signal sources, the mixing gain adjustment circuit performs mixing gain adjustment. Its main purpose is to adjust the signal strength of each audio source according to the volume balance set by the user, so as to obtain a mixed signal with moderate volume. This process ensures that the audio signals from the electric guitar and the AUX interface can achieve an ideal volume balance after mixing, avoiding the problem of excessive or insufficient volume. The adjusted mixed signal is further amplified by the headphone amplifier processing circuit to fit the standard volume played by the headphone. The headphone amplifier processing circuit further amplifies the mixed signal to ensure that the headphones can receive sufficient audio signal strength to reach the ideal volume level. The audio signal processed by the headphone amplifier is output to the headphone jack, and the user can monitor the mixed audio content through the headphones. This processing method can ensure that the audio output by the headphone is both clear and has a suitable volume.

[0023] In some further preferred embodiments, the mixing gain adjustment circuit includes an operational amplifier U6 and a variable resistor VR6; the input end of the operational amplifier U6 is the input end of the mixing gain adjustment circuit, and is electrically connected to the output end of the external effector and the output end of the AUX interface audio signal processing circuit, the output end of the operational amplifier U6 is connected to the input end of the variable resistor VR6, the ground end of the variable resistor VR6 is grounded, and the variable resistance adjustment end of the variable resistor VR6 is electrically connected to the input end of the headphone amplifier processing circuit; the operational amplifier U6 and the variable resistor VR6 jointly adjust the mixing gain of the received audio signal to be mixed and the electric guitar signal to be mixed to obtain the mixing signal with a moderate volume, and the variable resistance adjustment end of the variable resistor VR6 outputs the mixing signal with a moderate volume to the headphone amplifier processing circuit for headphone amplifier processing. It should be noted that the input end of the mixing gain adjustment circuit receives signals from two different signal sources: one from the output end of the external effector, and the other from the output end of the AUX interface audio signal processing circuit. After pre-processing, these signals are the electric guitar signal to be mixed and the AUX interface audio signal to be mixed. After receiving these two signals, the operational amplifier U6 mixes and adjusts their gain. As the core component of gain adjustment and signal mixing, the operational amplifier's gain value will be adjusted according to the strength of the input signal. The function of the variable resistor VR6 is to further adjust the gain of the mixed signal. The variable resistor has three ports: the ground end of the variable resistor is connected to the ground; the input end of the variable resistor is connected to the output end of the operational amplifier U6, which is used to receive the signal mixed by the operational amplifier; the adjustment end of the variable resistor (i.e., the variable resistance adjustment end) is connected to the input end of the headphone amplifier processing circuit, and the adjusted signal with moderate volume is output to the headphone amplifier for further amplification. The adjustment end of the variable resistor is the part for adjusting the volume, which can finely adjust the gain of the signal to obtain a mixed signal with moderate volume. The adjusted mixed signal with moderate volume is output to the headphone amplifier processing circuit through the variable resistor VR6, and this signal is further amplified by the headphone amplifier and output to the headphones. This process can ensure that the signal played through the headphones can meet the volume requirements and maintain good sound quality. It is understandable that in this embodiment, the operational amplifier U6 and the variable resistor VR6 work together to ensure that the ideal volume balance can be achieved after the signal is mixed. The variable resistor VR6 allows the volume to be accurately adjusted according to actual needs, so that the final output mixed signal has a moderate volume effect. Through the adjustment end of the variable resistor, the volume can be adjusted according to needs during use to avoid excessive or low volume output and ensure the comfort of audio monitoring. The variable resistor VR6 provides an adjustable gain function, which supports real-time adjustment of the mixed volume according to the strength of the input signal and the need for sound effects. Unlike simple fixed gain adjustment, the adjustable nature of the variable resistor provides more flexibility, making the tuning process more refined and personalized.The signal strengths from different sources (electric guitar and AUX interface) can be balanced by the coordinated work of operational amplifier U6 and variable resistor VR6. Since these signals usually have different levels, the correct gain adjustment ensures that they are balanced in the final mix without the problem of too strong or too weak signals. The gain adjustment and signal mixing capabilities of operational amplifier U6 ensure that the signals remain clear and high-fidelity when mixed. With the refinement of the mixing gain adjustment, the final audio signal will not be distorted, nor will there be audio hum or noise.

[0024] In some further preferred embodiments, the headphone amplifier processing circuit includes: an operational amplifier U7 and an operational amplifier U8; the input ends of the operational amplifier U7 and the operational amplifier U8 are connected to the variable resistance adjustment end of the variable resistor VR6, and the output ends of the operational amplifier U7 and the operational amplifier U8 output the mixed signal suitable for headphone playback; the operational amplifier U7 and the operational amplifier U8 receive the mixed signal with a moderate volume output by the variable resistance adjustment end of the variable resistor VR6, amplify the received mixed signal with a moderate volume, and obtain the mixed signal suitable for headphone playback. Among them, the mixed signal suitable for headphone playback can be connected to the headphone through the headphone interface HEADPHONES. It should be noted that the input ends of the operational amplifier U7 and the operational amplifier U8 receive the signal from the variable resistance adjustment end of the variable resistor VR6. This signal is a mixed signal with a moderate volume after the previous mixing gain adjustment, representing the final audio output signal, which has been mixed and gain adjusted for different audio sources (such as electric guitar signals and AUX interface audio signals). The operational amplifier U7 and the operational amplifier U8 further amplify the mixed signal with a moderate volume. Headphones usually require a higher audio level to ensure sufficient volume output, so operational amplifiers U7 and U8 will adjust the amplification factor according to the input signal strength to ensure that the signal is within the level range suitable for headphone playback. The amplified signal is output through the output terminals of operational amplifiers U7 and U8 and can be connected to the headphone interface HEADPHONES. This signal is a mixed signal suitable for headphone playback and can directly drive the headphones for audio output.

[0025] 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 preamplifier module circuit of a mixing console, characterized in that: include: The electric guitar signal input processing circuit is used to receive the electric guitar signal for buffering and to amplify the buffered electric guitar signal to obtain a standard level electric guitar signal output after the level is increased; A limiting circuit, electrically connected to the output end of the electric guitar signal input processing circuit, for performing level limiting processing after receiving the standard level electric guitar signal, so as to obtain a fidelity electric guitar signal output whose level does not exceed a first threshold range; A sound effect adjustment circuit is electrically connected to the output end of the limiting circuit and is used to perform sound effect adjustment after receiving the fidelity electric guitar signal to obtain a preliminary mixed electric guitar signal output adapted for mixing processing; an attenuation circuit, electrically connected to the output end of the sound effect adjustment circuit, for receiving the preliminary mixed electric guitar signal and then performing level attenuation processing to obtain an effector input signal whose level does not exceed the second threshold range and transmit it to an external effector, wherein the external effector further performs sound effect adjustment on the effector input signal to obtain an electric guitar signal to be mixed that is adapted for mixing processing; An AUX interface audio signal processing circuit is used to receive the AUX interface audio signal and then amplify it to obtain an audio signal to be mixed whose level matches that of the electric guitar signal to be mixed; The mixed signal output processing circuit is electrically connected to the output end of the external effector and the AUX interface audio signal processing circuit, and is used for receiving the audio signal to be mixed and the electric guitar signal to be mixed, and then adjusting the mixing gain to obtain a mixed signal with a moderate volume, and performing headphone amplifier processing on the mixed signal with a moderate volume to obtain a mixed signal suitable for headphone playback for output to the headphone.

2. The preamplifier module circuit of the mixing console as claimed in claim 1, characterized in that: The electric guitar signal input processing circuit includes an input buffer circuit and a gain amplifier circuit, wherein the output end of the input buffer circuit is electrically connected to the input end of the gain amplifier circuit; after the input end of the input buffer circuit is connected to the electric guitar signal, the input buffer circuit performs buffer processing on the connected electric guitar signal to obtain a buffered electric guitar signal and outputs it to the gain amplifier circuit, and the gain amplifier circuit performs gain amplification on the buffered electric guitar signal to obtain a standard level electric guitar signal output after the level is increased.

3. The preamplifier module circuit of the mixing console as claimed in claim 2, characterized in that: The input buffer circuit includes an operational amplifier U1. After the input end of the operational amplifier U1 is connected to the electric guitar signal, the operational amplifier U1 performs buffering processing on the connected electric guitar signal to obtain a buffered electric guitar signal and output it to the gain amplifier circuit.

4. The preamplifier module circuit of the mixing console as claimed in claim 3, characterized in that: The gain amplifier circuit includes an operational amplifier U2 and a variable resistor VR1; the input end of the operational amplifier U2 and the input end of the variable resistor VR1 are commonly connected to receive the buffered electric guitar signal; the output end of the operational amplifier U2 and the output end of the variable resistor VR1 are commonly connected to output the standard level electric guitar signal; the variable resistance adjustment end of the variable resistor VR1 is grounded; the operational amplifier U2 and the variable resistor VR1 jointly perform gain amplification processing on the buffered electric guitar signal to obtain a standard level electric guitar signal with amplified level.

5. The preamplifier module circuit of the mixing console as claimed in claim 4, characterized in that: The limiting circuit includes an operational amplifier U3, the input end of the operational amplifier U3 is connected to the output end of the operational amplifier U2 and the output end of the variable resistor VR1, and is used to receive the standard level electric guitar signal. The operational amplifier U3 performs level limiting processing on the received standard level electric guitar signal to obtain a fidelity electric guitar signal output whose level does not exceed a first threshold range.

6. The preamplifier module circuit of the mixing console as claimed in claim 5, characterized in that: The sound effect adjustment circuit includes an equalizer EQ; the input end of the equalizer EQ is connected to the output end of the operational amplifier U3, and is used to receive the fidelity electric guitar signal; the equalizer EQ performs sound effect adjustment on the received fidelity electric guitar signal to obtain a preliminary mixed electric guitar signal output adapted for mixing processing.

7. The preamplifier module circuit of the mixing console as claimed in claim 6, characterized in that: The attenuation circuit includes an operational amplifier U4, the input end of which is connected to the output end of the equalizer EQ, for receiving the preliminary mixed electric guitar signal; the operational amplifier U4 performs level attenuation processing on the received preliminary mixed electric guitar signal to obtain an effector input signal whose level does not exceed a second threshold range and transmits it to an external effector.

8. The preamplifier module circuit of the mixing console as claimed in claim 7, characterized in that: The output end of the operational amplifier U4 is connected to the input end of the external effector through the socket FX SEND to transmit the effector input signal to the external effector for processing; the output end of the external effector is connected to the input end of the mixing signal output processing circuit through the socket FX RETURN to transmit the electric guitar signal to be mixed to the mixing signal output processing circuit for processing.

9. The preamplifier module circuit of the mixing console as claimed in claim 8, characterized in that: The AUX interface audio signal processing circuit includes an operational amplifier U5; after the input end of the operational amplifier U5 is connected to the AUX interface audio signal, the operational amplifier U5 amplifies the AUX interface audio signal to obtain an audio signal to be mixed whose level matches the electric guitar signal to be mixed; the output end of the operational amplifier U5 is connected to the mixed signal output processing circuit, and outputs the audio signal to be mixed to the mixed signal output processing circuit for processing.

10. The preamplifier module circuit of a mixing console according to any one of claims 1 to 9, characterized in that: The mixed signal output processing circuit includes a mixing gain adjustment circuit and a headphone amplifier processing circuit; the input end of the mixing gain adjustment circuit is electrically connected to the output end of the external effector and the output end of the AUX interface audio signal processing circuit, the output end of the mixing gain adjustment circuit is electrically connected to the input end of the headphone amplifier processing circuit, and the output end of the headphone amplifier processing circuit outputs the mixed signal suitable for headphone playback; the mixing gain adjustment circuit performs mixing gain adjustment on the received audio signal to be mixed and the electric guitar signal to be mixed to obtain a mixed signal with a moderate volume and output it to the headphone amplifier processing circuit, and the headphone amplifier processing circuit performs headphone amplifier processing on the mixed signal with a moderate volume to obtain the mixed signal suitable for headphone playback.

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