Power Amp Board Bluetooth Digital 2.1 Channel Subwoofer Module for TDA7498E Chip ZK HT21 Item Type: Power Amp Board Material: Metal Bluetooth Compatibility Version: 5.0(unobstructed, 15m) Input Method: Auxiliary and bluetooth compatible and USB Channel Number: 2.1 Channel(left channel, right channel, subwoofer) Chip: TDA7498E Adapter Power Supply: DC15~36V(undervoltage protection below 9V, also support 12V power supply) Speaker: 30-200W, 4-8Ω Output Power: Left and right channels <=160W, subwoofer <=220W Safety Protection: Prevent reverse connection, undervoltage, overheat, overcurrent, short circuit protection Sufficient output power is only available when the audio signal input is large enough and the power supply voltage or current is large enough. Ensure that the adapter power is higher than the actual operating power of the amp. The higher the power supply voltage, the higher the output power; the lower the speaker impedance, the higher the output power.