1. Support one digital coaxial input, one digital optical fiber input, one HDMI input, one ARC audio return transmission input, one Bluetooth 5.0 input, one USB playback input and USB computer sound card input, you can switch freely between different signal sources.  2. Support a set of 5.1 channel analog audio output, any signal input decoding and playback support 5.1 or 2.0 channel output options, can be flexibly configured according to the number of speakers. The latest Bluetooth 5.0 transmission method can automatically detect and be compatible with Bluetooth devices, PRO version supports mobile phone APP control.  3. Using 24 bit/192KHz audio DSP, the fourth generation 24bit/192KHz DAC six-channel chip, with power-on reset function. Support Dolby Digital AC3, DTS, LPCM, HDCD, PCM, Dolby digital, Dolby Prologic & 8545; and other digital audio format decoding. Support U disk multimedia playback, can play 5.1 channel and lossless music and other multimedia content, the maximum capacity is 128G/FAT32 format. Support first-level folder playback, and the remote control can also quickly select 1-10 songs to play.  4. High-quality sound quality, low noise, mute and reset function on the computer, better protection of the rear stage and equipment. One-key switch input source, easy and fast operation, support simple operation of panel keys and infrared remote control operation. LED on the panel indicates the working status, and it is controlled by an external multi-function infrared remote control. Black oxidized metal casing, stable and decent.  5. Power off memory function, automatically switch to the last used signal channel after restarting, USB play memory files before power off. Front panel work indicator, the corresponding indicator is always on when there is signal input, and the corresponding indicator flashes when there is no signal input. Use DC 12V/1A external power adapter for power supply, wide voltage can use DC (7-20V) power supply.  Three-dimensional product size: external power adapter for power supply, wide voltage can use DC (7-20V) power supply.    Three-dimensional product size: 205mm (width) x 68mm (deep) x 30mm (height).  Specifications:  Support digital audio decoding format: Dolby Digital(AC3)/DTS/PCM  USB playback audio format: MP3 / APE / FLAC / WAV / DTS / AC3  HDMI input resolution: 3840 x 2160 (30HZ)  DSP sampling frequency: 32~192KHz  DSP bit rate: 16~24 Bit  Digital input level: 0.1~1V p-p  5.1 Analog output (1kHz@0dB): greater than equal 1.5V RMS  Signal-to-noise ratio @0dB (CCIR/ARM): greater than equal 90dB  Distortion: less than equal 0.03%  Frequency response: 20Hz~20KHz  Maximum working current: 700mA  Power adapter specifications: AC 100V-240V 50/60Hz, DC 12V/1A  Plug Type:US Plug,it applies to Canada, India,Mexico, Thailand, the United States, the Philippines,Taiwan and so on.