{"product_id":"bluetooth-power-amplifier-board-stereo-2-1-channel-2x220w-350w-hifi","title":"Bluetooth Power Amplifier Board Stereo 2.1 Channel 2X220W+350W - HiFi","description":"\u003cp\u003eIn this review of the Bluetooth Power Amplifier Board Stereo ZK-AS21, the bottom line is simple: this board is for DIY audio builders and hobbyists who want a compact, powerful 2.1 amplifier with modern inputs and respectable Hi-Fi ambitions. The reviewer found the TPA3251D2 class D chips deliver clear, loud output without excessive heat, and the module's flexible inputs (Bluetooth 5.1, AUX, USB, U disk) make it easy to drop into a small desktop or bookshelf system. If you need raw power and multiple input options in a compact package, this board is worth considering.\u003c\/p\u003e\n\u003ch2\u003eKey Features\u003c\/h2\u003e\n\u003cul\u003e\n\u003cli\u003e\n\u003cstrong\u003eHigh-power 2.1 output:\u003c\/strong\u003e The board supplies up to 220W to each left and right channel and 350W to a subwoofer, letting small systems reach high listening levels with solid bass support.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eFlexible inputs:\u003c\/strong\u003e Built-in Bluetooth 5.1, AUX, USB and U disk support allow connections from phones, PCs, TVs and USB storage without extra converters.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eModern Bluetooth control:\u003c\/strong\u003e The upgraded Bluetooth supports APP control, adjustable volume and timed shutdown for convenient remote tweaks and playlist interaction.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eTPA3251D2 class D chips:\u003c\/strong\u003e Uses two high-performance TI amplifier chips for efficient operation and low distortion across the audio band for cleaner sound at high power.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eProtection features:\u003c\/strong\u003e Short circuit, overcurrent, undervoltage and overheating protection reduce the risk of damage and allow automatic recovery from faults.\u003c\/li\u003e\n\u003cli\u003e\n\u003cstrong\u003eSpeaker compatibility:\u003c\/strong\u003e Supports a wide range of speaker impedances and power ratings, accommodating L\u0026amp;R channels from 30-220W and subwoofers from 30-350W.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003ch2\u003eWho It's For\u003c\/h2\u003e\n\u003cp\u003eThis amplifier board suits DIY audio enthusiasts building powered bookshelf, desktop or compact home theater systems who need a single board solution for left\/right and subwoofer channels with both wired and wireless inputs. It also fits makers integrating a high-power audio stage into custom enclosures or media furniture where space is limited and efficiency matters.\u003c\/p\u003e\n\u003cp\u003eThose who should look elsewhere include users seeking an all-in-one consumer receiver with built-in voice assistants, HDMI switching or polished consumer remote controls; this module is a technical component rather than a finished living-room appliance and requires a suitable 12-38V power supply and appropriate speakers.\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 rated power per channel and a robust subwoofer output provide room-filling sound when fed with sufficient power.\u003c\/li\u003e\n\u003cli\u003eMultiple input options including Bluetooth 5.1 and USB make source connectivity straightforward and modern.\u003c\/li\u003e\n\u003cli\u003eGood build quality and efficient TPA3251D2 chips mean lower waste heat and cleaner sound under load.\u003c\/li\u003e\n\u003cli\u003eComprehensive protection systems help prevent damage from wiring or thermal faults.\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003e\u003cstrong\u003eCons\u003c\/strong\u003e\u003c\/p\u003e\n\u003cul\u003e\n\u003cli\u003eRealized output depends heavily on supply voltage\/current and input signal level, so users must provide an adequate power supply to reach rated power.\u003c\/li\u003e\n\u003cli\u003eNot a finished consumer product: some users may find the need for external enclosures, wiring and cooling inconvenient compared with ready-made amps.\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-AS21\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eChannels\u003c\/td\u003e\n\u003ctd\u003e2.1 (L + R + Subwoofer)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eOutput Power\u003c\/td\u003e\n\u003ctd\u003e2x220W + 350W (max, with sufficient supply)\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eBluetooth\u003c\/td\u003e\n\u003ctd\u003eVersion 5.1 with APP control\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eAudio Inputs\u003c\/td\u003e\n\u003ctd\u003eBluetooth, AUX, USB, U disk, USB sound card\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003ePower Supply\u003c\/td\u003e\n\u003ctd\u003eDC 12-38V, 10A recommended\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003ctr\u003e\n\u003ctd\u003eProtection\u003c\/td\u003e\n\u003ctd\u003eReverse connection, undervoltage, overcurrent, overheating, short circuit\u003c\/td\u003e\n\u003c\/tr\u003e\n\u003c\/table\u003e\n\u003ch2\u003eOur Verdict\u003c\/h2\u003e\n\u003cp\u003eThe Bluetooth Power Amplifier Board ZK-AS21 is a compelling choice for experienced DIYers who want a compact, high-power 2.1 solution with modern wireless and USB inputs. It delivers strong volume, clear sound courtesy of TI TPA3251D2 chips and useful protections, but needs a proper power supply and a bit of technical assembly to reach its full potential, making it a good value for builders rather than plug-and-play buyers.\u003c\/p\u003e\n\u003ch2\u003eFrequently Asked Questions\u003c\/h2\u003e\n\u003cp\u003e\u003cstrong\u003eWhat power supply does this board need?\u003c\/strong\u003e\u003cbr\u003eThe board accepts DC 12-38V; for high output use a supply capable of delivering adequate current (10A or more) to reach rated power.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eCan it drive passive subwoofers and speakers?\u003c\/strong\u003e\u003cbr\u003eYes; it supports both active and passive output modes and is rated for L\u0026amp;R speakers 30-220W and subwoofers 30-350W.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eDoes it include overheating and short-circuit protection?\u003c\/strong\u003e\u003cbr\u003eYes; the board includes protection for short circuit, overcurrent, undervoltage and overheating with automatic recovery when conditions safe return.\u003c\/p\u003e","brand":"MakerHawk","offers":[{"title":"Default Title","offer_id":46759630438619,"sku":"B0B3D4786D","price":46.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0724\/1043\/1707\/files\/71awZA_LKGL._SL1500.jpg?v=1747854520","url":"https:\/\/gearmusthave.com\/products\/bluetooth-power-amplifier-board-stereo-2-1-channel-2x220w-350w-hifi","provider":"GearMustHave","version":"1.0","type":"link"}