Feature:1. TPA3255 HIFI Chip: The XY S350H power amplifier board uses two TPA3255 power amplifier chips. Support wide voltage input of 1838V, power up to 220W x 2+350W (PMPO).2. High Compatibility: The DC adapters on the market (plug size 5.5mm x 2.1mm) can basically meet the needs of the XY S350H Bluetooth power amplifier board. If you don't have a DC plug, please don't worry, you can also directly connect the positive and negative poles of the wire to the power socket of the amplifier board.3. Reble And Bass Control: If you are tired of an amplifier with only one volume knob, then you feel right, because you have further requirements for audio. By adjusting the high and low frequency knobs of the XY S350H power amplifier board, you can make the sound more layered and make the bass more shocking.4. Protection Function: XY S350H Bluetooth power amplifier board has multiple protection mechanisms to ensure its safe operation. With short circuit protection, undervoltage protection, overvoltage protection, clipping protection.5. AUX Audio Connection: Independent adjustment of left and right channels for high and low frequencies. 360 degree infinite tuning.Specification:Item Type: Bluetooth Power Amplifier BoardProduct Material: PCBWeight: Approx. 375g / 13.2ozBluetooth Version: 5.1Signal To Noise Ratio: 92dBFrequency Range: 20Hz-20KHzPower Supply: DC 18-38V/10A Or AboveAudio Channel: 2.1 ChannelsAudio Output: Left And Right Channels And SubwooferAudio Input: Bluetooth, AUX, USB Drive, USB Sound CardOutput Power: 2 x 220W (Left And Right Channels), 350W (Bass)Maximum Output Power Of Left And Right Channels: 220W/32--36VDC 175W/42--36VDC 100W/82--36VDCMaximum Output Power Of Subwoofer: 355W/2--36VDC 250W/3--36VDC 195W/4--36VDCSubwoofer Adapter Speaker: 20W-200W/2-8Volume Adjustment: High End Encoder Knob Adjustment, Smooth TouchProtection Mechanism: Overvoltage, Undervoltage, Overheating, Clipping, Short Circuit Protection, Etc.APP: Support for YS Audio APP Control.Package List:1 x Power Amplifier Board 1 x Upper Cover Plate 1 x Lower Cover Plate 5 x Button Cap 4 x M2x18 Copper Column 8 x M2x3mm Screw 4 x M2x4+3 Copper Column 1 x Screwdriver Note:1. The working voltage of the power amplifier board must be higher than 18V. A DC voltage below 18V will not activate the power amplifier board.2. Please ensure that the power of the adapter power supply is greater than the actual working power of the amplifier!3. Note: When using the app, all app permissions must be opened in the phone settings. Otherwise, some phones may have compatibility issues, resulting in Bluetooth not being able to connect.