Diamond Audio MICRO84U 4-Channel Full Range Class D Amplifier

Four channels of clean, efficient power in a chassis that fits where others won't. The Diamond Audio MICRO84U is a 4-channel full range Class D amplifier built for speaker-focused builds — run all four channels full-range, or bridge pairs for a serious 2-channel setup with 300W x 2 at 4 ohms. Either way, you're getting MICRO-series efficiency in a package that doesn't demand a dedicated amp rack.

Power output scales with your load: 80W x 4 at 4 ohms, 150W x 4 at 2 ohms, and 300W x 2 bridged at 4 ohms. The Class D design keeps draw low and output clean — no wasted heat, no bloated current demand, just usable power where it counts.

Like every amp in the MICRO-U series, the MICRO84U is built for environments that would kill a standard amplifier. The conformal-coated circuit board seals out moisture, salt air, and dust — making this a legitimate choice for marine audio, motorcycle builds, ATVs, UTVs, and any outdoor install where weather exposure is a real concern. This isn't a "splash-resistant" marketing claim; it's the same all-weather construction used across the MICRO-U lineup.

Integration is straightforward. Selectable REM, VOX, and DC turn-on modes handle compatibility with factory and aftermarket head units, while selectable 2CH or 4CH input modes give you flexibility depending on your source configuration. The variable 40–400Hz crossover (12dB/oct) and adjustable input sensitivity (0.2–10V) let you tune the amp to your speakers rather than the other way around.

At 9.1" x 4.1" x 1.46", the MICRO84U fits under seats, inside fairings, and in console compartments where a conventional 4-channel simply won't go.

Key Features

• 4-channel full range Class D amplifier
• 80W x 4 @ 4Ω / 150W x 4 @ 2Ω / 300W x 2 bridged @ 4Ω
• Conformal-coated PCB — all-weather rated for marine & powersports
• Selectable REM / VOX / DC turn-on modes
• Selectable 2CH / 4CH input modes
• Variable 40–400Hz crossover (12dB/oct)
• Adjustable input sensitivity: 0.2–10V
• Compact chassis: 9.1" x 4.1" x 1.46"
• RCA input & speaker output harness kits included