What is claimed is:1. A 5 GHz multichannel lossless wireless audio system, formed by a transmitter and multiple receivers, wherein:the transmitter comprises a main signal processing portion, a 5G wireless transmitting portion, a first single chip portion, a Light Emitting Diode (LED) indicating and displaying panel portion, and a first power supply portion, wherein the main signal processing portion comprises a universal interface unit, a digital audio processing unit, a multichannel analog input unit, a multichannel Analog-to-Digital Converter (ADC), a first high speed multiway switch, and a second high speed multiway switch; the universal interface unit comprises a coaxial input interface, a surface panel optical fiber input interface, a rear panel optical fiber input interface, Audio Engineering Society (AES)/European Broadcasting Union (EBU) digital input interface, Bluetooth? antenna, Universal Serial Bus (USB) input interface and TYPE-C input interface; the digital audio processing unit comprises a digital audio receiving module and an asynchronous sampling rate conversion module; an output end of the multichannel analog input unit is connected to an input end of the multichannel ADC; control ports of the first single chip portion are respectively connected to control ports of the TYPE-C input interface, the digital audio receiving module, the asynchronous sampling rate conversion module, and the 5G wireless transmitting portion; the LED indicating and displaying panel portion and the first power supply portion are respectively connected to the first single chip portion; the coaxial input interface, the surface panel optical fiber input interface, the rear panel optical fiber input interface, the AES/EBU digital input interface and the TYPE-C input interface are respectively connected to an input interface of the digital audio receiving module; the Bluetooth? antenna and an output interface of the digital audio receiving module are simultaneously connected to the first high speed multiway switch; the USB input interface has two signal output ends, one of which is connected to the first high speed multiway switch, and another one of which is connected to the asynchronous sampling rate conversion module; an output end of the asynchronous sampling rate conversion module and an output end of the multichannel ADC are simultaneously connected to the second high speed multiway switch; an output end of the second high speed multiway switch is connected to the 5G wireless transmitting portion;each of the multiple receivers comprises a 5G wireless receiving portion, a digital/analog conversion and power amplifying portion, a second single chip portion, a LED indicating panel portion, and a second power supply portion; the digital/analog conversion and power amplifying portion comprises a third high speed multiway switch, a digital/analog signal converter with volume control, a low speed filter buffer unit, an analog switch, a power amplification module, a Radio Corporation of America (RCA) single-end analog signal output interface, an External Line Return (XLR) balanced analog audio input interface and a speaker; the 5G wireless receiving portion is wirelessly connected to the 5G wireless transmitting portion via a 5 GHz signal; the 5G wireless receiving portion is connected to the digital/analog signal converter with volume control; an analog volume output interface of the digital/analog signal converter with volume control is connected to the low speed filter buffer unit; the low speed filter buffer unit has two output ends, one of which is connected to the RCA single-end analog signal output interface, and another one of which and the XLR balanced analog audio input interface are simultaneously connected to the analog switch; an output end of the analog switch is connected to the power amplifying module; a speaker output interface of the power amplifying module is connected to the speaker; control ports of the second single chip portion are respectively connected to control ports of the 5G wireless receiving portion and the digital/analog conversion and power amplifying portion; the LED indicating panel portion and the second power supply portion are respectively connected with the second single chip portion.2. The 5 GHz multichannel lossless wireless audio system of claim 1, wherein the USB input interface is a USB 2.0 interface or a USB 3.0 interface.3. The 5 GHz multichannel lossless wireless audio system of claim 1, wherein the 5G wireless transmitting portion comprises a baseband portion, a digital cache portion, a 5 GHz radio frequency portion, and 5 GHz duplex dual antenna transmission signals.4. The 5 GHz multichannel lossless wireless audio system of claim 1, wherein the multichannel analog input unit comprises a multichannel analog interface and a buffer amplifier.5. The 5 GHz multichannel lossless wireless audio system of claim 1, wherein the first single chip portion comprises a first system control microprocessor, and a 2/8Channel (CH) switch, an infrared remote control unit and a first remote control interface connected respectively to the first system control microprocessor.6. The 5 GHz multichannel lossless wireless audio system of claim 1, wherein the LED indicating and displaying panel portion comprises a status display unit and a volume control and display unit, wherein the status display unit is connected to the first single chip portion; the volume control and display unit comprises a volume knob, a shift register, and an LED digital display screen; the volume knob is connected to the first single chip portion; the shift register and the LED digital display screen are connected to the first single chip portion through the shift register.7. The 5 GHz multichannel lossless wireless audio system of claim 1, wherein the Bluetooth? antenna is connected to the first high speed multiway switch through a Bluetooth? module; the USB input interface is respectively connected to the first high speed multiway switch and the asynchronous sampling rate conversion module through a USB interface conversion chip.8. The 5 GHz multichannel lossless wireless audio system of claim 1, wherein the power amplification module has a power of 200 W.9. The 5 GHz multichannel lossless wireless audio system of claim 1, wherein the second single chip portion comprises a second system control microprocessor, and a local attenuation control unit, a channel setting unit, a human-machine interaction component, an infrared remote control receiving interface, an infrared remote control switch, a 12V output switch control unit and a second remote control interface respectively connected to the second system control microprocessor, wherein the infrared remote control switch is connected to the infrared remote control receiving interface.10. The 5 GHz multichannel lossless wireless audio system of claim 1, wherein the LED indicating panel portion comprises a 48-192 khz sampling rate indicating unit and a wireless signal indicating unit simultaneously connected to the second single chip portion.