Isolation preamplifier

Abstract

The utility model belongs to the technical field of amplifiers, and particularly relates to an isolation preamplifier. Comprising a sound mixing circuit, two amplifiers, three audio isolation units, a line input unit, a microphone input unit, a forced insertion microphone input unit, a power supply module, a silence detection unit, a silence adjusting circuit, a volume treble and bass adjusting circuit and an audio output unit. According to the utility model, multiple functions are integrated, through mutual cooperation and optimization design of all the parts, high-quality and high-performance audio processing and output functions can be provided, and the performance and the function of the isolation preamplifier are remarkably improved, so that the requirements of users on the tone quality and the function of different audio systems are better met.

Description

Technical Field

[0001] The utility model belongs to the technical field of amplifiers, and in particular relates to an isolation preamplifier. Background Art

[0002] An isolation preamplifier is an audio device that is commonly used in audio systems. It is designed to improve the purity and sound quality of audio signals by minimizing interference and crosstalk between different signal sources. Ordinary isolation preamplifiers on the market usually have a simple and intuitive design, consisting of an input interface, isolation circuit, mixing circuit, volume control circuit and sound quality adjustment circuit, and are designed to provide audio signal processing and adjustment functions.

[0003] However, this isolation preamplifier has the following disadvantages:

[0004] 1. Signal crosstalk: In an audio system, different input signals may interfere with each other, resulting in reduced audio quality and impaired overall performance;

[0005] 2. Insufficient isolation: Existing isolation preamplifiers may have deficiencies in audio signal input isolation, making it difficult to eliminate interference signals and affecting the clarity and purity of audio signals;

[0006] 3. Mixing distortion of multi-channel audio signals: The mixing circuit may have mixing distortion problems, resulting in a decrease in the quality of the output audio signal;

[0007] 4. Inflexible adjustment of output volume and sound quality: Some current isolation preamplifiers may not be flexible enough in terms of volume and sound quality adjustment, and cannot meet users' needs for output audio signals. Utility Model Content

[0008] The utility model aims to provide an isolation preamplifier to solve the problems existing in the prior art.

[0009] In order to achieve the above-mentioned purpose, the technical solution adopted by the utility model is an isolation preamplifier, including a mixing circuit, two amplifiers, three audio isolation units, a line input unit, a microphone input unit, a forced microphone input unit, a power module, a mute detection unit, a mute adjustment circuit, a volume high and low tone adjustment circuit and an audio output unit, the two amplifiers are electrically connected to the mixing circuit respectively, one end of an audio isolation unit is directly electrically connected to the mixing circuit and the other end is electrically connected to the line input unit, one end of the other two audio isolation units is electrically connected to the two amplifiers one by one and the other ends are respectively electrically connected to the microphone input unit and the forced microphone input unit, the power module is electrically connected to the mixing circuit, one end of the mute detection unit is electrically connected to the amplifier connected to the forced microphone input unit, one end of the mute adjustment circuit is electrically connected to the mute detection unit and the other end is electrically connected to the mixing circuit, one end of the volume high and low adjustment circuit is electrically connected to the mixing circuit, and one end of the audio output unit is electrically connected to one end of the volume high and low adjustment circuit away from the mixing circuit.

[0010] Preferably, a priority control switch CD4049UBE is electrically connected between the forced insertion microphone input unit and the audio isolation unit for receiving an audio signal inputted by an external emergency or higher priority microphone.

[0011] Preferably, the amplifier is of model STMicroelectronics TDA7294V.

[0012] Preferably, the audio isolation unit is a transformer isolator and the model is Pulse Electronics HX1188NL or Bel Magnetic Solutions 8100.

[0013] Preferably, the voltage of the power module is 9V or 12V.

[0014] Preferably, the silent detection unit is a power detector.

[0015] Compared with the prior art, the advantages and positive effects of the utility model are:

[0016] The utility model includes a mixing circuit, different types of input units (including a line input unit, a microphone input unit and a forced microphone input unit), an audio isolation unit, a mute detection unit, a sound quality adjustment circuit, etc., and has multiple functions and is suitable for different audio input scenarios. It has three audio isolation units, which are respectively connected to the line input, the microphone input and the forced microphone input, and can effectively isolate the signals between different input sources to prevent interference and crosstalk, and improve the purity and clarity of the audio signal. The mute control function can be realized through the mute detection unit and the mute adjustment circuit, that is, when the microphone input is forced, other audio input signals are suppressed to avoid unnecessary noise and interference, and the output audio quality is improved. A volume high and low tone adjustment circuit is provided, which can flexibly Adjust the volume and sound quality parameters of the output audio signal to meet the various requirements of users for audio output. Through the combination of carefully designed mixing circuits and audio isolation units and other components, high-quality audio mixing and output can be achieved to ensure the high fidelity of audio signals. Multi-channel signal input and microphone input can meet the needs of more complex audio systems and provide more diverse input options. The signal isolation circuit design is more rigorous, effectively blocking the interference between different audio input signals and improving audio quality and purity. The forced insertion of microphone input and the adjustable mute depth of audio signals can more effectively control the priority between different input signals. The mixing circuit and volume, high and low bass adjustment circuit design are more sophisticated, which can provide clearer and more outstanding output audio signals.

[0017] In general, this isolation preamplifier design integrates multiple functions. Through the mutual coordination and optimized design of various components, it can provide high-quality, high-performance audio processing and output functions. The performance and functions of the isolation preamplifier are significantly improved, thereby better meeting the user's requirements for sound quality and functions of different audio systems. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] In order to more clearly illustrate the technical solutions of the embodiments of the utility model, the following is a brief introduction to the drawings required for use in the description of the embodiments. Obviously, the drawings described below are some embodiments of the utility model. For ordinary technicians in this field, other drawings can be obtained based on these drawings without creative labor.

[0019] Figure 1 A schematic diagram of the structure of an isolated preamplifier. DETAILED DESCRIPTION

[0020] In order to more clearly understand the above-mentioned purpose, features and advantages of the utility model, the utility model is further described below in conjunction with the accompanying drawings and embodiments. It should be noted that the embodiments of the present application and the features in the embodiments can be combined with each other without conflict.

[0021] In the following description, many specific details are set forth to facilitate a full understanding of the present invention. However, the present invention may also be implemented in other ways than those described herein. Therefore, the present invention is not limited to the specific embodiments of the following disclosure.

[0022] In this embodiment, Figure 1 As shown, the specific design of the above-mentioned key components is described in detail below: an isolation preamplifier, including a mixing circuit, two amplifiers, three audio isolation units, a line input unit, a microphone input unit, a forced microphone input unit, a power module, a silent detection unit, a silent adjustment circuit, a volume high and low tone adjustment circuit and an audio output unit, the two amplifiers are electrically connected to the mixing circuit respectively, one end of an audio isolation unit is directly electrically connected to the mixing circuit and the other end is electrically connected to the line input unit, one end of the other two audio isolation units is electrically connected to the two amplifiers one by one and the other ends are respectively electrically connected to the microphone input unit and the forced microphone input unit, the power module is electrically connected to the mixing circuit, one end of the silent detection unit is electrically connected to the amplifier connected to the forced microphone input unit, one end of the silent adjustment circuit is electrically connected to the silent detection unit and the other end is electrically connected to the mixing circuit, one end of the volume high and low adjustment circuit is electrically connected to the mixing circuit, and one end of the audio output unit is electrically connected to an end of the volume high and low adjustment circuit away from the mixing circuit.

[0023] The audio signal can come from two sources, one is the line input unit, which is used to receive the line audio signal, and the other is the microphone input unit and the forced microphone input unit, which are used to receive the microphone audio signal. The line audio signal, the microphone audio signal and the forced microphone audio signal are isolated and processed respectively through three audio isolation units, so as to prevent interference and crosstalk between different input signals. The isolated audio signal enters the mixing circuit, and the mixing circuit combines all the signals into one output signal. The mixed signal is amplified by two amplifiers to increase the amplitude of the signal. The mute detection unit detects the volume of the forced microphone input signal and increases its priority so that it can suppress other input signals. The mute adjustment circuit adjusts the volume of other audio signals in the output signal according to the detected mute level to ensure that other audio signals can be appropriately suppressed when there is a forced microphone input. The volume level adjustment circuit is used to adjust the overall volume level of the output signal. The adjusted audio signal is output through the audio output unit and can be connected to a speaker or other external device for playback. The various devices work together to isolate, mix, amplify and prioritize audio signals from different sources to achieve precise adjustment and control of the output audio signals.

[0024] A priority control switch CD4049UBE is electrically connected between the forced microphone input unit and the audio isolation unit for receiving an audio signal of an external emergency or higher priority microphone input. The amplifier model is STMicroelectronics TDA7294V, the audio isolation unit is a transformer isolator and the model is PulseElectronics HX1188NL or Bel Magnetic Solutions 8100, the voltage of the power module is 9V or 12V, and the silent detection unit is a power detector.

[0025] Using CD4049UBE as a priority control switch can achieve fast switching and priority processing of external emergency or higher priority microphone input signals. This ensures that in an emergency, the sound of the emergency microphone can be transmitted first, improving the emergency response capability of the system. STMicroelectronics TDA7294V is used as an amplifier. This model of amplifier has good audio amplification performance and stability, can provide high-quality audio amplification effects, and ensure the clarity and fidelity of the output signal. Pulse Electronics HX1188NL or Bel Magnetic Solutions 8100 transformer isolators are used as audio isolation units, which can effectively isolate interference and noise between different input signals and improve the purity and quality of audio signals. The 9V or 12V voltage provided by the power module can meet the power requirements of each module of the system, ensuring stable and reliable operation of the system. The power detector is used as a silent detection unit, which can accurately detect the volume level of the forced microphone input signal, realize automatic adjustment of other audio signals in the output signal, and improve the intelligence and adaptability of the system. In summary, the use of these devices can ensure that the isolated preamplifier system has good audio processing capabilities, stability and reliability, while enabling effective management and priority processing of different audio signals, improving the overall performance and application scope of the system.

[0026] The contents not described in detail in this specification belong to the prior art known to professionals in this field.

[0027] The above description is only a preferred embodiment of the present invention and does not limit the present invention in other forms. Any technician familiar with the profession may use the technical content disclosed above to change or modify it into an equivalent embodiment with equivalent changes and apply it to other fields. However, any simple modification, equivalent change and modification made to the above embodiment based on the technical essence of the present invention without departing from the content of the technical solution of the present invention still falls within the protection scope of the technical solution of the present invention.

Claims

1. An isolation preamplifier, characterized in that: It includes a mixing circuit, two amplifiers, three audio isolation units, a line input unit, a microphone input unit, a forced microphone input unit, a power module, a mute detection unit, a mute adjustment circuit, a volume high and low tone adjustment circuit and an audio output unit. The two amplifiers are electrically connected to the mixing circuit respectively, one end of an audio isolation unit is directly electrically connected to the mixing circuit and the other end is electrically connected to the line input unit, one end of the other two audio isolation units are electrically connected to the two amplifiers one by one and the other ends are respectively electrically connected to the microphone input unit and the forced microphone input unit, the power module is electrically connected to the mixing circuit, one end of the mute detection unit is electrically connected to the amplifier connected to the forced microphone input unit, one end of the mute adjustment circuit is electrically connected to the mute detection unit and the other end is electrically connected to the mixing circuit, one end of the volume high and low tone adjustment circuit is electrically connected to the mixing circuit, and one end of the audio output unit is electrically connected to one end of the volume high and low tone adjustment circuit away from the mixing circuit.

2. The isolation preamplifier according to claim 1, characterized in that: A priority control switch CD4049UBE is electrically connected between the forced insertion microphone input unit and the audio isolation unit, and is used to receive an audio signal input by an external emergency or higher priority microphone.

3. An isolation preamplifier according to claim 2, characterized in that: The amplifier model is STMicroelectronics TDA7294V.

4. The isolation preamplifier according to claim 3, characterized in that: The audio isolation unit is a transformer isolator and the model is Pulse Electronics HX1188NL or Bel Magnetic Solutions 8100.

5. The isolation preamplifier according to claim 4, characterized in that: The voltage of the power module is 9V or 12V.

6. The isolation preamplifier according to claim 5, characterized in that: The silent sound detection unit is a power detector.

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