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Rockford Fosgate PM400X4
Upgrade Your Vehicle With Confidence. This Is Built to Fit, Perform, and Last
Rockford Fosgate PM400X4: High-Performance 4-Channel Marine Amplifier for Superior Sound Quality
The Rockford Fosgate PM400X4 is a high-performance 4-channel amplifier engineered to deliver powerful, clear audio in marine and powersport environments. With 400 watts of RMS power, this versatile amplifier is perfect for driving multiple speakers or a combination of speakers and subwoofers, ensuring that every note is reproduced with clarity and precision. Whether you're outfitting a boat, ATV, or UTV, the PM400X4 provides the power and durability needed to elevate your listening experience, even in the harshest conditions.
Experience Powerful, Clear Audio with the Rockford Fosgate PM400X4
The Rockford Fosgate PM400X4 amplifier is designed to deliver crisp, powerful audio that brings your music to life, no matter where your adventures take you. With its high-efficiency Class-AD design, this 4-channel amplifier ensures consistent power delivery, resulting in distortion-free sound across all channels. Whether you're enjoying your favorite tracks on the water or the trails, the PM400X4 ensures that your audio system performs at its best, providing balanced, full-range audio with exceptional clarity.
Built for Marine and Powersport Durability
The Rockford Fosgate PM400X4 is built to withstand the rigors of marine and powersport environments. Featuring corrosion-resistant, conformal-coated circuit boards, this amplifier is protected against moisture, salt, and other elements that can damage electronics. Its rugged, compact chassis is designed for easy installation in tight spaces, making it an ideal choice for boats, ATVs, and UTVs. The PM400X4 also includes a variable crossover and high/low pass filters, allowing you to optimize the sound for your specific setup.
Versatile Performance for Various Audio Setups
The Rockford Fosgate PM400X4 offers versatile performance, making it suitable for a wide range of audio configurations. It can power four full-range speakers with 50 watts RMS each at 4 ohms or 100 watts RMS each at 2 ohms, or it can be bridged to deliver 200 watts RMS to two speakers or subwoofers. This flexibility allows you to tailor your marine or powersport audio system to your preferences, whether you're aiming for balanced sound or seeking to add extra punch to your bass.
Key Features:
- 400-Watt 4-Channel Amplifier: Delivers 50 watts RMS per channel at 4 ohms, 100 watts RMS per channel at 2 ohms, or 200 watts RMS when bridged at 4 ohms.
- High-Efficiency Class-AD Design: Ensures consistent power delivery for clear, distortion-free sound.
- Marine-Grade Construction: Corrosion-resistant materials and conformal-coated circuit boards protect against moisture and salt.
- Variable Crossover and High/Low Pass Filters: Optimize sound quality for your specific audio setup.
- Compact, Rugged Chassis: Designed for easy installation in tight spaces, perfect for marine and powersport applications.
Why Choose the Rockford Fosgate PM400X4?
The Rockford Fosgate PM400X4 is the ideal choice for marine and powersport enthusiasts who want to add crisp, powerful audio to their system. With its high-efficiency design, marine-grade construction, and versatile performance, this amplifier provides the quality and reliability needed to drive your speakers and subwoofers to their full potential, even in the harshest environments. Whether you're upgrading your boat’s sound system or outfitting your ATV for the trails, the PM400X4 offers the power, precision, and durability you need for an exceptional audio experience.
Upgrade Your Marine or Powersport Audio with the Rockford Fosgate PM400X4
Ready to add clear, powerful sound to your marine or powersport audio system? Order the Rockford Fosgate PM400X4 400-watt 4-channel amplifier today and enjoy superior sound quality on every adventure.
Specifications:
| Specification | Details |
|---|---|
| Power Output (RMS) | 50 Watts x 4 Channels @ 4Ω, 100 Watts x 4 Channels @ 2Ω, 200 Watts x 2 Channels @ 4Ω (Bridged) |
| Frequency Response | 20 Hz – 20 kHz |
| Class | AD |
| Signal-to-Noise Ratio | >100 dB |
| Variable Crossover | 50 Hz – 250 Hz |
| Dimensions | 8.3" x 6.8" x 2.4" |
FAQs
Q: What power output does the Rockford Fosgate PM400X4 amplifier provide?
A: The PM400X4 delivers 50 watts RMS per channel at 4 ohms, 100 watts RMS per channel at 2 ohms, or 200 watts RMS when bridged at 4 ohms, making it ideal for driving speakers or subwoofers.
Q: Is the PM400X4 amplifier suitable for marine environments?
A: Yes, the PM400X4 features marine-grade construction, including corrosion-resistant materials and conformal-coated circuit boards, making it ideal for marine and powersport applications.
Q: What type of amplifier is the PM400X4?
A: The PM400X4 is a Class AD 4-channel amplifier, designed for high efficiency and clear, powerful audio performance in demanding environments.
Q: Does the Rockford Fosgate PM400X4 have customizable sound controls?
A: Yes, the PM400X4 includes a variable crossover and high/low pass filters, allowing you to optimize the sound quality for your specific audio setup.
Q: Why should I choose the Rockford Fosgate PM400X4 amplifier for my marine or powersport vehicle?
A: The PM400X4 amplifier offers crisp, powerful sound with marine-grade durability, easy installation, and versatile performance, making it an excellent choice for upgrading your audio system in challenging environments.
Upgrade Your Audio Experience on the Water or Trails!
Don’t miss out on the opportunity to elevate your marine or powersport audio system with clear, powerful sound. Order the Rockford Fosgate PM400X4 now and enjoy an exceptional audio experience on every adventure.
- Ships within 1–3 business days from our warehouse
- Tracking included with every order
- Free 30-day returns if it doesn’t work for your setup
- 2-year manufacturer warranty
- Authorized dealer guarantee
- Real installer-backed support before and after purchase

Why This Upgrade Makes Daily Driving Better
Ease of Use & Safety
Expandable by Design
FITMENT & INSTALLATION MADE SIMPLE
WHAT VEHICLES IT WORKS WITH
We verify compatibility before you buy, no guesswork.
DIY FRIENDLY IF:
- You're comfortable with basic tools
- You follow provided instructions
PROFESSIONAL INSTALL RECOMMENDED IF:
- Your vehicle requires dash kits or wiring adapters
- You want a turnkey experience
INSTALLATION CREDIT & SUPPORT:
- $75 Installation Credit when purchased online
- Speak to real installers before you buy
- Bring it into one of our locations for install
Why Buying This Here Is Safer Than Anywhere Else
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Installer Support
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Authorized Products
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Easy Returns
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Physical stores & real installers
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FREQUENTLY ASKED QUESTIONS
FREQUENTLY ASKED QUESTIONS
How do I know this stereo or speaker will fit my car?
Select your year, make, and model using the Vehicle Fit Guide at the top of the page. You’ll only see products that are compatible with your exact vehicle setup.
What happens if I order something that doesn’t fit?
You can return or exchange it within 30 days. We’ll help you identify the correct part for your vehicle so you don’t have to guess again.
Are these products brand new and covered by warranty?
Yes — all products are brand new, authentic, and sold as an authorized dealer, which means they include a full manufacturer warranty.
Can you install this for me, or do I need to do it myself?
You can do either. Install it yourself, or use your $75 installation credit at our shop and have it professionally installed by our team.
What if I don’t know what to choose for my car?
Tell us your vehicle and what you want to improve (sound, bass, CarPlay, etc.). We’ll recommend the exact products that fit your car and your budget.
