{"product_id":"diamond-audio-1-channel-micro81u-series-monoblock-class-d-amplifier","title":"Diamond Audio MICRO81U Monoblock Class D Subwoofer Amplifier","description":"\u003ch1\u003eDiamond Audio MICRO81U Monoblock Class D Subwoofer Amplifier\u003c\/h1\u003e\n\u003cp\u003eOne job. Done right. The \u003cstrong\u003eDiamond Audio MICRO81U\u003c\/strong\u003e is a \u003cstrong\u003emonoblock Class D amplifier\u003c\/strong\u003e purpose-built for subwoofer duty — delivering \u003cstrong\u003e300W RMS at 2 ohms\u003c\/strong\u003e or \u003cstrong\u003e175W RMS at 4 ohms\u003c\/strong\u003e in a chassis small enough to disappear into almost any install. If you're adding a sub to a motorcycle, boat, UTV, or a car with limited real estate, this is the amp that makes it happen without compromise.\u003c\/p\u003e\n\n\u003cp\u003eThe \u003cstrong\u003eClass D design\u003c\/strong\u003e is the right choice for a dedicated sub amp: high efficiency means less heat, less current draw, and more usable power delivered to your woofer. The \u003cstrong\u003evariable 40–400Hz crossover (12dB\/oct)\u003c\/strong\u003e gives you a wide tuning range to dial in the rolloff point for your specific sub and enclosure, and \u003cstrong\u003eadjustable input sensitivity (0.2–10V)\u003c\/strong\u003e handles everything from a factory head unit to a high-output aftermarket deck.\u003c\/p\u003e\n\n\u003cp\u003eBuilt on the same platform as the rest of the MICRO-U series, the MICRO81U features a \u003cstrong\u003econformal-coated circuit board\u003c\/strong\u003e that stands up to moisture, salt air, vibration, and dust. That makes it a real option for \u003cstrong\u003emarine audio builds, motorcycle installs, ATVs, UTVs, and any outdoor application\u003c\/strong\u003e where a standard amp would eventually fail. The all-weather rating isn't a checkbox — it's baked into the design.\u003c\/p\u003e\n\n\u003cp\u003e\u003cstrong\u003eSelectable REM, VOX, and DC turn-on modes\u003c\/strong\u003e keep integration simple whether you're working with a factory source unit or a full aftermarket setup. \u003cstrong\u003eSelectable 2CH or 4CH input modes\u003c\/strong\u003e add flexibility for different signal configurations, and the \u003cstrong\u003e10Hz–33kHz frequency response\u003c\/strong\u003e ensures the amp isn't the limiting factor in your low-end extension.\u003c\/p\u003e\n\n\u003cp\u003eAt \u003cstrong\u003e9.1\" x 4.1\" x 1.46\"\u003c\/strong\u003e, the MICRO81U fits in spaces where a conventional monoblock simply won't. Same footprint as the MICRO84U — so if you're building a mixed system, the amps stack and mount cleanly together.\u003c\/p\u003e\n\n\u003ch3\u003eKey Features\u003c\/h3\u003e\n\u003cp\u003e• \u003cstrong\u003e1-channel monoblock Class D amplifier\u003c\/strong\u003e\u003cbr\u003e\n• \u003cstrong\u003e300W x 1 @ 2Ω \/ 175W x 1 @ 4Ω RMS\u003c\/strong\u003e\u003cbr\u003e\n• \u003cstrong\u003eConformal-coated PCB\u003c\/strong\u003e — all-weather rated for marine \u0026amp; powersports\u003cbr\u003e\n• \u003cstrong\u003eVariable 40–400Hz crossover (12dB\/oct)\u003c\/strong\u003e\u003cbr\u003e\n• \u003cstrong\u003eAdjustable input sensitivity: 0.2–10V\u003c\/strong\u003e\u003cbr\u003e\n• \u003cstrong\u003eSelectable REM \/ VOX \/ DC turn-on modes\u003c\/strong\u003e\u003cbr\u003e\n• \u003cstrong\u003eSelectable 2CH \/ 4CH input modes\u003c\/strong\u003e\u003cbr\u003e\n• \u003cstrong\u003eCompact chassis: 9.1\" x 4.1\" x 1.46\"\u003c\/strong\u003e — same footprint as MICRO84U\u003cbr\u003e\n• \u003cstrong\u003eRCA input \u0026amp; speaker output harness kits included\u003c\/strong\u003e\u003c\/p\u003e","brand":"Diamond Audio","offers":[{"title":"Default Title","offer_id":43635027312707,"sku":null,"price":499.99,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0637\/9575\/7123\/files\/micro81u_2-3.webp?v=1785959941","url":"https:\/\/www.trinitycaraudio.com\/products\/diamond-audio-1-channel-micro81u-series-monoblock-class-d-amplifier","provider":"Trinity Car Audio","version":"1.0","type":"link"}