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MB Quart Nautic Mono Marine Amp, 400W Waterproof Subwoofer Amp

Sale price $194.99

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The MB Quart NA4-400.1 is a 400 watt mono Nautic amplifier for powersports and marine audio, with waterproof potted internals and quick release connectors. It is a compact full range Class D design rated IP67, so it can live in a UTV, boat or RV where water and dust reach the electronics.

As a mono marine amp and marine subwoofer amp, it drives a single subwoofer in a boat or a UTV subwoofer amp location under a seat. It works as a UTV amplifier, UTV amp, boat amplifier or general waterproof amplifier, and MB Quart lists it as the successor to the MB Quart NA2-400.1. If you are comparing MB Quart amplifier models for bass, this is the compact MB Quart amp to look at, and a sealed marine amplifier option for tight spaces.


Key Features

  • 400 watt max, mono full range Class D operation
  • 1 x 400 watts at 2 ohms
  • 1 x 200 watts at 4 ohms
  • IP67 waterproof and dustproof with potted internals
  • Q-Stasis low noise preamplifier stage
  • Quick connection power wires and RCA connections; Molex plug speaker connector
  • Protection circuits for thermal, overload, DC and speaker short with lighted indicators
  • Wired bass remote included
  • 1 pair nickel-plated RCA inputs

Built To Solve: Underpowered Speakers in UTVs and Boats

  • Speakers running off head unit power that distort over engine and wind noise
  • Car amplifiers that fail when water, dust or vibration reach the circuit board
  • No room for a large amplifier under a seat or console
  • Bulky screw terminals that are slow to service

Best For: UTV, Boat and RV Mono Amplifier Builds

  • UTV and side-by-side audio builds that need compact waterproof power
  • Boat and wake setups with marine speakers
  • RV and outdoor installs where the amp sees moisture
  • Subwoofer builds in UTVs and boats; MB Quart lists it as replacing the NA2-400.1

Specifications

  • Channels: mono
  • Power: 1 x 400 watts at 2 ohms
  • Power: 1 x 200 watts at 4 ohms
  • Crossover: Variable low pass 50Hz-150Hz; bass boost 0-12dB; subsonic filter 15Hz-50Hz
  • Signal to noise: > 100dB
  • Frequency response: 17Hz-165Hz
  • Input: RCA (1 pair)
  • Input sensitivity: 0.2-9V
  • THD: 1.0%
  • Power terminal: 12 AWG quick connector; speaker connection: Molex plug connector
  • Fusing: 30A x 1
  • IP rating: IP67, potted internals
  • Amp dimensions: 6.8 x 3.94 x 1.77 in; amp weight 2.2 lbs
  • Color: Black; warranty: 1 year
  • Manufacturer Part Number: NA4-400.1

Fitment

MB Quart lists this product as universal: it is not specific to one machine. Fitment is not guaranteed for every mounting location; confirm space, mounting and wiring for your UTV, boat or RV before ordering.


FAQ

Is the MB Quart NA4-400.1 waterproof?

Yes. MB Quart states it meets or exceeds IP67 standards for waterproof and dustproof and uses potted internals that seal the components.

How much power does the NA4-400.1 make?

MB Quart rates it at 400 watts max: 1 x 400 watts at 2 ohms; 1 x 200 watts at 4 ohms.

Will it fit my UTV?

MB Quart lists the Nautic amplifiers as universal. At 6.8 x 3.94 x 1.77 inches it is compact, but confirm a mounting location and wiring path in your machine before ordering.

How do I connect it?

Power uses 12 AWG quick connectors, inputs are nickel-plated RCA, and speaker outputs use a Molex plug connector. MB Quart publishes a Nautic amplifier quick start guide.

Does it include a bass remote?

Yes. MB Quart includes a wired bass remote that adjusts gain level from anywhere in the vehicle.

What did it replace?

MB Quart lists the NA4-400.1 as the replacement for the NA2-400.1.


Why MB Quart

MB Quart's Nautic and Discus lines are built for open-air use on boats, UTVs and RVs, where sun, spray, dust and vibration are part of every trip. MB Quart backs this product with a 1 year warranty.


Pair the Nautic Mono Amplifier With the Right Speakers

Match the NA4-400.1 to speakers and impedance using MB Quart's ratings, and plan a power kit and fuse for your machine or boat. Dunes 2 Dezert SXS carries MB Quart Nautic speakers, Discus amplifiers and powersports wiring kits to complete the system.

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