A816 Dual-Chip ACM8816 High-Power GaN Digital Bluetooth Amplifier Board – Audiophile-Grade Remote-Controlled Decoding Amplifier 300w+300w on 48V DC

Instructions for Use Speaker Compatibility: The output of the amplifier board can only be connected to passive speakers. Do not connect it to active speakers or constant-voltage speakers. Power Supply Requirements: The amplifier board operates on a DC 24V–48V power supply. Higher voltage results in higher output power, but the voltage must not exceed 48V, otherwise, the amplifier will burn out. The required power plug size is 5.5 × 2.5 mm, with a center-positive and outer-negative polarity. Operation & Controls: Powering On: When connected to power for the first time, the screen will light up and the device will turn on automatically. Volume & Input: Turn the encoder knob directly to adjust the volume. Short-press the knob to switch between input sources (alternatively, using the remote control is more convenient). Buttons: Short-press the left button to mute. Long-press the left button to enter standby mode, and long-press it again to power the device back on. Wiring Warning: The negative terminals (-) of the left and right audio output channels must not be connected together, otherwise, it will cause the amplifier to burn out. Bluetooth Mode: To use Bluetooth, switch the input source to USB/BT. Search for the Bluetooth device named "YJCO-QCC3084" on your phone and connect to play audio. USB Audio Mode: * To use USB playback, switch the input source to USB/BT mode. The USB input can be connected directly to a computer or a smartphone for plug-and-play audio (no driver installation needed). When connecting a phone via OTG, you must use a proper OTG cable; a standard charging cable will not work. Note: This USB port cannot read USB flash drives (U-disks) directly.