Memphis Audio MX800.4
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Memphis Audio MX800.4 Powersports 4-Channel Amplifier
Product Overview:
The Memphis Audio MX800.4 is a compact, high-output Class D amplifier specifically engineered for the demanding environments of powersports, marine, and UTV applications. Despite its small footprint, it delivers a massive 800W RMS total power. Its ultra-durable design features an IP66 rating, making it completely resistant to dust and high-pressure water, ensuring your music keeps playing through mud, rain, or ocean spray.
Key Features
Extreme Weather Protection
Built to survive where standard amplifiers fail, the MX800.4 features conformal-coated circuit boards that protect internal components from moisture and corrosion. The unit is equipped with sealed connectors for power and signal, and the control panel is shielded by a water-resistant top cover, ensuring the sensitive tuning dials remain dry and functional in any weather.
Installer-Friendly "Top-Mount" Controls
In tight powersports installations, accessing side-mounted controls can be nearly impossible. Memphis solved this by placing all crossover and gain controls on the top of the amplifier. This allows you to easily fine-tune the sound even after the unit is mounted in a cramped glove box or under a dash.
Versatile Power Configurations
The MX800.4 is highly flexible, offering 4-channel, 3-channel, or 2-channel (bridged) modes. You can use it to power four high-output speakers at 200W each, or bridge two channels to drive a subwoofer with 400W RMS while the remaining two channels handle your front speakers.
Seamless Integration
Equipped with a 2/4 channel input switch, this amplifier can create a 4-channel output even if your head unit only has a single set of RCA outputs. It also supports both high-level (speaker) and low-level (RCA) inputs, making it compatible with both aftermarket stereos and factory-installed systems.
Technical Specifications
| Category | Specification |
| Power Output (RMS) | 125W x 4 @ 4Ω / 200W x 4 @ 2Ω |
| Bridged Power (RMS) | 400W x 2 @ 4Ω |
| Total RMS Power | 800 Watts |
| Amplifier Class | High-Efficiency Class D |
| Weather Rating | IP66 (Water, Dust, and Element Resistant) |
| Frequency Response | 10Hz – 20kHz |
| THD @ 4Ω | < 1% |
| Input Range | 300mV – 9.7V |
| Recommended Wire | 8-Gauge Power/Ground (8GKIT) |
| Dimensions (L x W x H) | 8.35" x 4.35" x 1.75" |
What Others Are Saying
Eddie was great - SDCS installed a new head unit in my 2019 4Runner. He was honest in his opinions regarding the options I was considering. Pricing was also good - he was able to reuse some of my existing installation kit so I saved a bit of $$.Installation was clean and fast and he took the time to walk through the features before I left. Highly recommend!!
I had a great time at this shop! The staff really knows their stuff and took the time to explain the different options without pressure. Installation was quick, clean and professional. Everything looks factory and sounds amazing. The prices were fair and customer service was above and beyond. I highly recommend this place if you're looking for quality car audio and excellent service.
Those guys are really professional! I had a new Alpine floating head unit installed in my 2008 Mercedes, and it feels like a brand-new car. The installation was super clean. At first, the sound wasn’t the same as the factory stereo, but Kevin tuned it to be just as good—if not better—without adding any new amps. They even used my factory GPS antenna so I don’t have extra wires hanging out. On top of that, they matched the online price. Big thanks to Kevin and Eddie—highly recommended!
Kevin was awesome, he took his time and explained everything to me. I went in initially for a dash cam install and then decided to get a sub and amp installed as well. Both turned out great and will be returning if I need more work done.
Came In not knowing what to expect when suddenly my stereo stopped working. Spoke with Kevin in the front and after a VERY fast diagnosing they discovered my wiring was incorrect. After only about 45 minutes total being in the store I was on my way to the beach with a working stereo again! Thank you so much SDCARSTEREO
Highly recommend Kevin and the team at San Diego Car Stereo for any issues with aftermarket stereos. I bought a car with an aftermarket stereo and AC unit that wasn’t working properly—specifically, the heat wasn’t functioning due to an improper setup. I had several people look at it with no luck, and even the dealership basically refused to help because it was an aftermarket install. I came to Kevin and his team over the holidays feeling pretty defeated, but he was confident he could get the heat working before I headed back to a Colorado winter. Sure enough, he got it done.
FAQ
Do products purchased from San Diego Car Stereo come with a warranty?
Yes, all products come with a 1-year manufacturer warranty unless otherwise stated. This covers any defects excluding physical damage.
Are these products brand new?
Yes, every product we sell is 100% brand new, unused, and comes in original manufacturer packaging unless clearly marked otherwise.
Do you offer installation services?
Yes, we offer professional installation services at both of our San Diego Car Stereo locations. Our expert technicians have over 50 years of combined experience to install all of your car, marine, or offroad audio needs. Stop by or give us a call to schedule an appointment to get a quote in person.