{"product_id":"zk-st21-tpa3221-bluetooth-power-amplifier-board-2-1-channel-high","title":"ZK-ST21 TPA3221 Bluetooth Power Amplifier Board 2.1 Channel - High","description":"\u003cp\u003eOur review of the ZK-ST21 TPA3221 Bluetooth power amplifier board finds it best suited for hobbyists and DIY home audio builders who need a compact, high-power 2.1 channel amp that can drive bookshelf speakers and a subwoofer. The single biggest reason to consider this module is its TPA3221 HIFI chip design delivering a combined output capability up to 100W x2 + 200W, along with wide DC input range and dedicated treble and bass controls that make tonal shaping simple without extra gear.\u003c\/p\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eTPA3221 HIFI chip:\u003c\/strong\u003e Provides a stereo 2.1 channel configuration capable of sustained high-power output for clean, dynamic sound at higher volumes.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eWide voltage input:\u003c\/strong\u003e Accepts DC 12-30V so it works with a variety of power supplies and battery setups for flexible installation scenarios.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eMultiple inputs:\u003c\/strong\u003e Bluetooth, AUX, and USB drive inputs let the board accept audio from phones, TVs, laptops, and thumb drives without extra converters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTreble and bass control:\u003c\/strong\u003e Separate high and low frequency knobs allow quick tonal adjustment to emphasize clarity or deepen bass response depending on the speaker pairing.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProtection features:\u003c\/strong\u003e Built-in short-circuit, over-current, over-heat, and anti-reverse protection helps prevent damage during setup and operation.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThis amplifier board is aimed at DIY audio enthusiasts, small home theater builders, and hobbyists who want a compact, powerful amp to drive a pair of satellite speakers plus a subwoofer. Its multiple inputs and tone controls make it convenient as a small system head unit for a workshop, living room project, or PC audio upgrade.\u003c\/p\u003e\n\u003cp\u003eThose who need wireless reliability for long-distance streaming, finished consumer-grade enclosures with firmware support, or clinical level noise floors for studio monitoring should look elsewhere; the unit is a raw module suited to projects and installations rather than sealed consumer electronics.\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\u003eHigh power capability with the \u003cstrong\u003eTPA3221\u003c\/strong\u003e chip allowing strong drive for both speakers and subwoofer.\u003c\/li\u003e\n\u003cli\u003eFlexible connectivity including \u003cstrong\u003eBluetooth\u003c\/strong\u003e, AUX, and USB drive inputs for versatile source options.\u003c\/li\u003e\n\u003cli\u003eUseful treble and bass knobs make quick tonal adjustments without extra processors.\u003c\/li\u003e\n\u003cli\u003eBuilt-in protection mechanisms give practical safety during DIY installs.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eBluetooth performance and some functionality receive mixed feedback, so wireless behavior may vary by device and environment.\u003c\/li\u003e\n\u003cli\u003eAs a bare module it requires careful wiring and mounting; not ideal for users wanting a finished, plug-and-play enclosure.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eSpecifications\u003c\/h2\u003e\n\u003ctable\u003e\n\u003ctr\u003e\n\u003ctd\u003eChip\u003c\/td\u003e\n\u003ctd\u003eTPA3221 HIFI chip\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOutput power\u003c\/td\u003e\n\u003ctd\u003eUp to 100W x2 + 200W (2.1 channel)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInput voltage\u003c\/td\u003e\n\u003ctd\u003eDC 12-30V\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eInputs\u003c\/td\u003e\n\u003ctd\u003eBluetooth, AUX, USB drive\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eTone controls\u003c\/td\u003e\n\u003ctd\u003eTreble and Bass knobs\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProtections\u003c\/td\u003e\n\u003ctd\u003eShort-circuit, over-current, over-heat, anti-reverse\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch2\u003eOur Verdict\u003c\/h2\u003e\n\u003cp\u003eThe ZK-ST21 is a strong-value amplifier board for DIYers who want high power and tonal control in a compact package; its \u003cstrong\u003eTPA3221\u003c\/strong\u003e-based design and multiple inputs make it versatile for home audio projects, though it behaves best when mounted and wired carefully rather than used as a finished consumer product.\u003c\/p\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eCan this board run from a 12V battery?\u003c\/strong\u003e\u003cbr\u003eYes, it accepts DC 12-30V so it can be powered from a 12V battery or compatible supply, but ensure the supply can deliver sufficient current for high output levels.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it include protection against wiring mistakes?\u003c\/strong\u003e\u003cbr\u003eThe module includes anti-reverse, short-circuit, over-current, and over-heat protections to reduce risk during installation and operation.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eWill Bluetooth work reliably for all phones?\u003c\/strong\u003e\u003cbr\u003eBluetooth connectivity is supported, but user reports are mixed; performance can vary with device compatibility and signal environment.\u003c\/p\u003e","brand":"DAJUNGUO","offers":[{"title":"Default Title","offer_id":48687033024731,"sku":"B0CXX7TG5V","price":35.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/71xkffjoRML._AC_SL1500.jpg?v=1778709242","url":"https:\/\/gearmusthave.com\/products\/zk-st21-tpa3221-bluetooth-power-amplifier-board-2-1-channel-high","provider":"GearMustHave","version":"1.0","type":"link"}