Rockford Fosgate PM400X4 Punch Marine 400 Watt 4-Channel Amplifier

Real Power. Real Protection. Real Punch.

Product Overview

The Rockford Fosgate PM400X4 is a 400 Watt, 4-channel Class A/B amplifier purpose-built for marine, motorsport, and powersports environments and flexible enough to handle virtually any vehicle audio setup. Delivering 50W x 4 at 4 ohms, 100W x 4 at 2 ohms, or 200W x 2 bridged at 4 ohms, it brings genuine CTA-2006-rated output to boats, UTVs, 4WDs, and utes running in the harshest Australian conditions.

What sets this amp apart from the competition is its Rockford Fosgate Element Ready™ construction a combination of marine-grade two-part epoxy-coated circuit boards, UV and corrosion-resistant hardware, and a cast aluminium heatsink engineered to dissipate heat in tight, sun-baked enclosures. Whether you're running a 4-way front-stage/rear-fill setup or a 3-way front-stage/subwoofer system, the PM400X4 is tuned and ready to deliver The PUNCH.

Key Specifications

• 400W total power output (CTA-2006 compliant)
• 50W x 4 channels at 4 ohms | 100W x 4 channels at 2 ohms
• 200W x 2 channels at 4 ohms (bridged)
• Class A/B circuit topology
• 4-channel configuration; bridgeable
• Frequency response: 20 Hz – 20 kHz (±1 dB)
• THD+N: Less than 1% at rated power
• Input sensitivity: 150mV – 12V (low- and high-level)
• Crossover: 12 dB/octave Butterworth, 50 Hz – 250 Hz (HP/LP)
• On-board Punch EQ2: Bass +0 to +18 dB @ 45 Hz | Treble +0 to +12 dB @ 12.5 kHz (front and rear)
• Marine-grade two-part epoxy conformal coating on PCB
• Marine-grade stainless steel hardware
• Element Ready™ protection: Dust, UV, Temperature, Water, Corrosion & Vibration
• 2-year manufacturer warranty

Features & Benefits

Marine-Grade Element Ready™ Construction The PM400X4 isn't just weather-resistant it's built for full marine deployment. The two-part epoxy conformal coating and stainless steel hardware protect against saltwater spray, humidity, mud, and vibration. Perfect for tinnie setups on the Swan or long offshore runs.

Class A/B Trans•ana Topology Rockford Fosgate's Trans•ana circuit design simplifies the signal path, delivering a flat, distortion-free frequency response from 20 Hz to 20 kHz. Real-world dynamic performance that outperforms the spec sheet independent testing has measured distortion below 0.02%.

C.L.E.A.N. Gain Setting Technology Calibrated Level Eliminates Audible Noise. The integrated LED clip indicators guide you to a perfect gain match between your head unit and amplifier no distortion, no guesswork, no blown tweeters. Front and rear channels have independent C.L.E.A.N. indicators (Blue: <0.5% THD | Violet: 1% THD | Red: 10%+ THD).

High-Level Input with Auto Turn-On Connects directly to factory head units with speaker-level outputs no line output converter required. The Auto Turn-On circuit senses the audio signal and powers the amp automatically. Ideal for Aussie utes running OEM head units where an RCA tap isn't an option.

On-Board Punch EQ2 with Bass & Treble Boost Dial in up to +18 dB of bass boost at 45 Hz and +12 dB of treble presence at 12.5 kHz per channel pair all from the stealth top-mounted control panel. Tune to taste for everything from skull-rattling subwoofer punch to crisp, open-air speaker clarity.

Versatile 3- or 4-Way System Configuration Run 4-way full-range (front and rear speakers), 3-way (front component speakers bridged into a subwoofer pair), or 2-channel bridged mode for two high-excursion subs. One amplifier, multiple system options.

MEHSA³ Cast Aluminium Heatsink Maximum Efficiency Heat Sink Application construction achieves up to five times better heat transfer than traditional mounting methods. Keeps the amp cool even when installed in enclosed bays or under fibreglass critical for Australian summers.

Muted Turn-On Eliminates the pop or thump through your speakers at power-on a small but important detail that protects tweeters and subwoofers during ignition cycling.

Technical Specs

Compatible With

Marine & Boat Audio

• Rockford Fosgate Punch Marine speaker range (PM series)
• Rockford Fosgate M2WL Wake Tower Speakers (6.5", 8", 10")
• Rockford Fosgate M2D4-12 Marine Subwoofers
• Tinnie, ski boat, pontoon, and cabin cruiser installs
• Paired with Rockford Fosgate PMX-5CAN Marine Head Unit

Motorsport & Powersports

• Side-by-side UTVs (Can-Am, Polaris RZR, Yamaha YXZ)
• Rockford Fosgate UTV-specific speaker and sub packages
• Roll cage and overhead speaker bar mounts

4WD, Ute & Touring Vehicles

• Toyota LandCruiser (100, 200, 300 Series), Prado, HiLux
• Ford Ranger, Everest, Bronco
• Isuzu D-MAX / MU-X
• Nissan Patrol, Navara
• Mitsubishi Triton, Pajero Sport
• Any vehicle running an OEM (factory) head unit via high-level input

Compatible Rockford Fosgate Accessories

• RFI-1 Amplifier Wiring Installation Kit (recommended for extended warranty)
• Rockford Fosgate Punch component speaker sets (P165-SI, P1675)
• Rockford Fosgate Punch subwoofers (P2D4-10, P3D4-12)

Frequently Asked Questions

Does this amplifier work with a factory (OEM) head unit?

Yes. The PM400X4 features a high-level input that accepts speaker-level signals (up to 12V) directly from a factory head unit, with Auto Turn-On sensing no line output converter or aftermarket head unit required.

Can the PM400X4 be used to run a subwoofer?

Yes. Bridge channels 3 and 4 (rear pair) to deliver 200W into a 4-ohm subwoofer, while running full-range component speakers on channels 1 and 2. This creates a complete 3-way front-stage/sub system from a single amplifier.

Is this amplifier suitable for a boat in saltwater conditions?

Yes. The PM400X4 is built with marine-grade two-part epoxy conformal-coated circuit boards and corrosion-resistant stainless steel hardware as part of Rockford Fosgate's Element Ready™ construction, rated for dust, UV, temperature, water, corrosion, and vibration exposure.

What does the C.L.E.A.N. system do and do I need it?

C.L.E.A.N. (Calibrated Level Eliminates Audible Noise) uses onboard LED indicators to guide precise gain matching between your source and amplifier, eliminating clipping distortion that damages speakers. It removes guesswork from setup and is highly recommended for any install.

What warranty applies to the PM400X4 in Australia?

The PM400X4 carries a 2-year manufacturer warranty. Australian warranty terms are administered through the authorised local distributor confirm coverage details at point of purchase, as Rockford Fosgate's US warranty terms apply only to products purchased through US-authorised dealers.