Bluetooth 5.1 Audio Amplifier Board, ZK-AS21 2.1CH 220W x 2 + 350W HiFi Amp Subwoofer Power Amp Mini Digital Audio Amp Module for Home Speakers(30-220W, 3-8Ohms), DC 16-38V, BT USB AUX Input

[ 2.1 CH Subwoofer Audio Amplifier Board] This AS-21 power amplifier is 2.1 channel, letting you connect 2 passive speakers and drive a subwoofer. It comes with Treble and Bass buttons, independent subwoofer volume adjustment buttons and 20-200Hz subwoofer frequency adjustment buttons, which is very friendly for audiophiles. You can adjust the Treble and Bass buttons to make the bass more shocking and the treble clearer, making the sound more layered. [220W*2 + 350W High Power Output] This AS-21 audio amplifier has 220W*2 output power for the left and right channels and 350W output power for the subwoofer.

It can drive two high-power speakers (30-220W, 3-8 ohms) and one subwoofer (30-350W, 2-8 ohms), and the adapted power supply is DC16-38V/10A or above.
Note: The higher the power supply voltage/current, the higher the output power; the lower the speaker resistance, the higher the output power. The adapted power supply should be higher than the actual working power of the amplifier. [HIFI Audio Power Amplifier] The ZK-AS21 power amplifier board has two built-in TPA3255 power amplifier chips. TPA3255 is a high-performance class D power amplifier chip that can make the device maintain ultra-low distortion in the whole audio frequency band and show high-definition sound quality at the same time. The wiring around the chip is a window tin spraying design to increase the output power. 6 x Low noise preamplifiers 5532 group can improve the sound quality and volume, and increase the gain. [Multiple Audio Input Modes] This Mini amplifier receiver has built-in Bluetooth 5.1, USB flash disk, USB sound card and 3.5 mm AUX Input. Bluetooth 5.1 mode offers faster transmission speed, lossless decoding, lower distortion rate, and a connection distance to audio equipment of 15m/49ft.
Note: When using AUX mode, please confirm that the Bluetooth connection of this module has been disconnected. [With Protective Function] This Bluetooth Amp module is designed with multiple protection mechanisms, including over-voltage protection, under-voltage protection, over-heat protection and short-circuit protection, with a case to protect it. Besides, there is a Long-life Ultra Silent Fan (locked rotor, no burning, no noise) above the audio chips, for heat dissipation and protection of the Bluetooth amplifier board