ZK-MT21 2.1 Channel, Bluetooth 5.0 Digital Power Amplifier Board, 50WX2+100W HiFi Subwoofer Audio AMP with Treble and Bass Control BT and AUX Inputs Module, DC12-24V Module for DIY Speakers

The ZK-MT21 is an all-in-one integrated Class D digital amplifier module specially designed for DIY audio enthusiasts, combining stereo amplifier, subwoofer drive and Bluetooth decoder on a single compact PCB board, no extra crossover circuit required. Equipped with advanced Bluetooth 5.0 wireless chip, it realizes ultra-stable low-latency audio transmission, quickly pairs with all Bluetooth-enabled devices including iPhone, Android smartphones, iPad, PC and smart TV. If you prefer wired audio playback, the 3.5mm AUX jack offers lossless wired input, the board automatically switches audio mode once AUX cable is plugged in for seamless use. Boasting powerful output performance, this amp board supplies 50W power for left and right satellite speakers separately and up to 100W strong output for passive subwoofer, bringing immersive surround sound and shocking deep bass effect for home movies, pop music, game audio and background music playback. Five independent adjustment knobs support full sound tuning: master volume, treble gain, bass gain, subwoofer volume and subwoofer cutoff frequency, allowing you to freely tweak high, mid and low frequency to get your ideal HiFi sound effect. To ensure long-term stable operation, the amplifier integrates complete four-fold safety protection: reverse power connection prevention, over-temperature auto cut-off, over-current protection and short-circuit protection. Thickened copper power terminals and speaker output terminals can bear large current without heating or loose wiring, greatly extending service life. With wide working voltage range DC12V-24V (5A power adapter required), it matches most common DC power supplies on the market, compatible with 4 ohm to 8 ohm speakers with rated power 20W-100W. Mini-sized body saves installation space, easy to embed into custom speaker cabinets, desktop audio boxes, small home theater equipment and commercial audio equipment for shops, cafes and offices. Warm Tips Please use DC 12-24V power adapter with rated current ≥5A; do not connect to 24V battery pack directly to avoid burning the board Match 4-8Ω impedance speakers within 20-100W power range; incorrect speaker parameters will cause distortion or damage Leave heat dissipation space when installing the board inside closed cabinet to prevent overheating

• Powerful 2.1 Channel Output: Max 50W left+50W right stereo + 100W dedicated subwoofer channel; Class D digital amplifier delivers clear stereo sound and deep heavy bass, perfect for building DIY 2.1 home audio speaker systems
• Dual Audio Input & Stable Bluetooth 5.0: Supports Bluetooth wireless streaming and 3.5mm AUX wired input; BT 5.0 provides 49 feet barrier-free transmission, fast pairing with phones, tablets, laptops, auto-switch to AUX when wired cable connected
• Full Tone Adjustable Control Knobs: Independent master volume, treble, bass, subwoofer volume and sub frequency rotary knobs; 360° stepless smooth tuning encoder, customize sound tone to match your music, movie and gaming preferences
• With Protective Function: This MT21 Bluetooth amp module is designed with over-voltage protection, under-voltage protection, over-heat protection, short-circuit protection, with case to protective it
• Wide Compatibility & Easy DIY Installation: Works with DC 12V-24V 5A+ power supply; fits 4-8Ω 20-100W speakers; compact size 93×90×22mm, lightweight 185g, ideal for home theater, desktop audio, retail store background music, custom speaker cabinet projects