{"product_id":"zk-mt21-2-1-channel-bluetooth-subwoofer-amplifier-board-module","title":"ZK-MT21 2.1 Channel Bluetooth Subwoofer Amplifier Board Module","description":"\u003cp\u003eOur review of the ZK-MT21 2.1 Channel Bluetooth Subwoofer Amplifier Board finds it best suited for DIY speaker builders and hobbyists who need a compact, highpower board with flexible tone control. The single biggest reason to buy is straightforward: it packs true 2 x 50W stereo plus a 100W subwoofer output in a palmsized PCB with Bluetooth 5.0 and AUX input, making it easy to upgrade bookshelf or custom enclosures without a bulky receiver. Installers will appreciate the builtin protections and adjustable treble and bass for fine tuning.\u003c\/p\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003e2.1 Channel Output:\u003c\/strong\u003e Delivers 2 x 50W to left\/right channels plus a 100W subwoofer channel for clear stereo and impactful low end.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eBluetooth 5.0 and AUX:\u003c\/strong\u003e Provides fast, stable wireless streaming and a wired AUX option so it works with phones, media players, and legacy sources.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eAdjustable Tone and Volume:\u003c\/strong\u003e Independent treble, bass, frequency and volume controls let the user tailor sound for different enclosures and speaker sizes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProtection Circuits:\u003c\/strong\u003e Antireverse connection, overheating, overcurrent and short circuit protection protect the board and connected drivers during setup and use.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eCompact and Compatible:\u003c\/strong\u003e Small 93 x 90 x 22mm PCB and support for 15-100W, 4-8 ohm speakers make it a flexible dropin for many DIY projects.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eComplete Kit:\u003c\/strong\u003e Ships with cover, bottom plate, adapter, screws and knob caps to simplify installation and finishing.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThe ZK-MT21 is ideal for DIY audio enthusiasts building custom 2.1 bookshelf systems, small powered multimedia speakers, or refurbishing vintage cabinets where a compact amplifier with a sub output is required. Its tone controls and protection features make it practical for makers who want adjustability without external DSP or complex cabling.\u003c\/p\u003e\n\u003cp\u003eIt is less suited to users who need network streaming, multiroom synchronization, or an integrated display and full remote control; for those use cases a full AV receiver or streaming amplifier would be a better choice.\u003c\/p\u003e\n\u003ch2\u003ePros \u0026amp; Cons\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003ePros\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eCompact 2.1 design with a strong 100W sub output for good bass extension in small enclosures.\u003c\/li\u003e\n\u003cli\u003eBluetooth 5.0 ensures a stable wireless connection alongside AUX for wired sources.\u003c\/li\u003e\n\u003cli\u003eBuiltin protections reduce the risk of damage from wiring mistakes or thermal stress during testing.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eNo builtin network streaming, remote, or display, so control is basic compared with full receivers.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003eModel\u003c\/td\u003e\n\u003ctd\u003eZK-MT21\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eChannels\u003c\/td\u003e\n\u003ctd\u003e2.1 Channels\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOutput Power\u003c\/td\u003e\n\u003ctd\u003e2 x 50W + 100W subwoofer\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBluetooth\u003c\/td\u003e\n\u003ctd\u003eBT 5.0\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInputs\u003c\/td\u003e\n\u003ctd\u003eBluetooth and AUX (support AUX+BT)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eSpeaker Compatibility\u003c\/td\u003e\n\u003ctd\u003e15-100W, 4-8 ohm speakers\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProtection\u003c\/td\u003e\n\u003ctd\u003eAntireverse, overheating, overcurrent, short circuit\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch2\u003eOur Verdict\u003c\/h2\u003e\n\u003cp\u003eThe ZK-MT21 is a compact, wellprotected 2.1 amplifier board that offers significant value for DIY builders who want Bluetooth streaming plus a dedicated subwoofer output. With flexible tone controls and a full accessory kit, it is a practical choice when space is limited and performance matters, though those wanting advanced streaming features should look elsewhere.\u003c\/p\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eCan this board drive passive subwoofers?\u003c\/strong\u003e\u003cbr\u003eYes, it provides a dedicated 100W subwoofer output suitable for passive subwoofers rated in the compatible power and impedance ranges.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWhat power supply range is required?\u003c\/strong\u003e\u003cbr\u003eThe board runs on DC12-24V as supplied and listed, so choose an adapter that matches the voltage and current needs of your speaker load.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it support tone adjustment?\u003c\/strong\u003e\u003cbr\u003eYes, it includes adjustable frequency, treble, bass and volume controls for tuning the system.\u003c\/p\u003e","brand":"Gugxiom","offers":[{"title":"Default Title","offer_id":46765375226075,"sku":"B0CZJZ9VFG","price":20.49,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/61UbmnPH8eL._AC_SL1500.jpg?v=1747854811","url":"https:\/\/gearmusthave.com\/products\/zk-mt21-2-1-channel-bluetooth-subwoofer-amplifier-board-module","provider":"GearMustHave","version":"1.0","type":"link"}