The JL Audio MM55 ($429.99) and the Fusion MS-RA210 ($399.99) are $30 apart, both NMEA 2000 certified, and both include a built-in amplifier. Comparing the built-in amps directly is trickier than it looks: JL Audio rates its amp in RMS (25W x4, 100W total), Fusion rates its in peak power (200W total). Those aren't the same measurement, and treating 200 as bigger than 100 would be comparing the wrong units.
Once that's sorted out, the real differences are zone count and display size.
Head-to-Head
| Spec | JL Audio MM55 | Fusion MS-RA210 |
|---|---|---|
| Price | $429.99 | $399.99 |
| Built-In Amp Rating | 25W RMS x4 (100W total RMS) | 200W peak (Class D) |
| Zones | 3, plus dedicated sub output each | 2 |
| Display | 2.8" full-color LCD | Not specified as a size on this listing |
| Water Rating | IP67 | Not numbered on this listing |
| NMEA 2000 | Yes | Yes, includes a 6' drop cable in the box |
Key Takeaways
- JL Audio's 25W RMS x4 (100W total RMS) and Fusion's 200W peak aren't directly comparable figures, RMS and peak measure different things, don't assume Fusion's is double the power.
- JL Audio's MM55 offers one more zone (3 vs 2) and a dedicated subwoofer output per zone, a more granular zone structure than the MS-RA210.
- Fusion's MS-RA210 includes a 6' NMEA 2000 drop cable in the box; JL Audio's listing doesn't specify an included cable.
- JL Audio publishes a numbered IP67 water rating; Fusion's MS-RA210 listing doesn't include one.
- Both are genuinely NMEA 2000 certified for Garmin, Lowrance, Raymarine, or Simrad MFD control.
Why You Can't Just Compare 100W to 200W
RMS measures continuous, sustained power output; peak measures the highest momentary output a circuit can produce, typically a much larger number than the RMS rating for the same amplifier. Fusion's "200 Watts peak power" figure for the MS-RA210 is not directly comparable to JL Audio's "25W RMS x4" rating for the MM55, they're different units of measurement, not different power tiers. Without a published RMS figure for the MS-RA210, a precise side-by-side power comparison between these two isn't possible from the listings alone.
Check the JL Audio MM55 → | Check the Fusion MS-RA210 →
Feature Walkthrough
Built-In Amplification
MM55: 4 channels, 25W RMS each (100W total RMS). MS-RA210: Class D amp rated at 200W peak power, with no separate RMS figure published on this listing.
Zones and Outputs
MM55 offers 3 zones with 9 total preamp channels and a dedicated subwoofer output per zone. MS-RA210 offers 2 zones without the same per-zone sub-output structure mentioned in its listing.
NMEA 2000 Setup
Both are NMEA 2000 certified. The MS-RA210 ships with a 6' NMEA 2000 drop cable included in the box, a small but real convenience JL Audio's listing doesn't call out as included.
Who Each One Is For
Choose the JL Audio MM55 if you want a third zone, dedicated per-zone sub outputs, and a documented IP67 rating. Choose the Fusion MS-RA210 if the lower price and an included NMEA 2000 cable matter more than the extra zone.
Honest Cons
Fusion's peak-power spec makes a precise RMS comparison impossible from the published listings, a real limitation for anyone trying to compare these two on power alone.
The MS-RA210 has one fewer zone than the MM55, relevant if a 3-zone build is part of your plan.
Neither listing publishes every spec the other does (numbered IP rating on Fusion's side, RMS wattage on Fusion's side), making a fully complete comparison impossible from the product pages alone.
Frequently Asked Questions
Is the Fusion MS-RA210's amp actually more powerful than the JL Audio MM55's?
Not verifiable from the published specs, Fusion states peak power (200W), JL Audio states RMS power (100W total), these measure different things and aren't directly comparable.
Which has more zones?
The JL Audio MM55, with 3 zones plus dedicated sub outputs, versus the MS-RA210's 2 zones.
Does the MS-RA210 include what I need to connect to NMEA 2000?
Yes, it ships with a 6' NMEA 2000 drop cable in the box, per its own listing.
How does the JL Audio MM55 compare to Kicker's stereos?
See our Kicker KMC5 vs. JL Audio MM55 comparison for that matchup.
Bottom Line
The MM55 offers an extra zone and clearer RMS documentation; the MS-RA210 costs less and includes its own NMEA cable. The power specs themselves can't be compared directly, don't let the raw numbers decide this one.