Factory sub relocating

LD50

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I had some time today to start checking some items off of my to do and upgrade list before I get the boat ready for final storage. We have a '25 M22. It came with the factory Rockford sub and one thing I haven't been able to stand is the location they chose to mount it. It takes up the entire compartment under the port front lounge seat. I removed it and just barely made it in the starboard side compartment that houses the trash can and fold out table. It's a tight fit, but works out great since that space is mostly useless anyway. The factory wiring harness is also long enough (just barely) to accommodate the new location.

Pulling the wires took the longest and I had to do it twice. If you run it straight forward under the rub rail and then across, which is the easiest way, it comes up a few feet short. It needs to be run under a couple of the trusses and then pulled across diagonally. Getting it under the trusses was a pain to do with the side skirt in place, but it's possible. It definitely helps to have some flexible polymer or fiberglass rods as a fishing tape was almost useless.

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I also found this when I removed the sub from its factory location. Come on Bennington, you can do better than this, especially with what we pay for these boats. It's not the worst thing I've seen, but it definitely makes me wonder what shortcuts they took in places I can't see. Almost as bad as looking at RVs during Covid.

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Interested in whether you find the location change affected the performance of the SubWoofer or not. My research suggests that placing this unit under the helm or swingback would result in significantly improved sound, as the roto-mold plastic can absorb some he energy and reduce performance. However, this is based on technical theory as I have yet to find anyone that tried a direct comparison.
 
Anecdotal only but my first impression was that it seemed to perform slightly better in this location. I didn't play it for too long, but for that short time I did think that it sounded almost acceptable in that location to the point where I could live with it if I had to. Once I add the 13.5 JL, I'll probably dial the factory one back a little just to fill in some mid-bass. I also wasn't overly concerned about the performance either way due to my upgrade plans.

Any perceived change in performance could be due to that compartment being a more rigid reinforced structure or different/shape volume. I could also be because of the seating and foam on top of factory location or possibly just my imagination. Maybe it's because that compartment has some venting that allows the air air to move whereas the original location is more sealed. I'm not an expert by any means, but having sealed sub inside a compartment without adequate venting seems like it would be less efficient.
 
Anecdotal only but my first impression was that it seemed to perform slightly better in this location. I didn't play it for too long, but for that short time I did think that it sounded almost acceptable in that location to the point where I could live with it if I had to. Once I add the 13.5 JL, I'll probably dial the factory one back a little just to fill in some mid-bass. I also wasn't overly concerned about the performance either way due to my upgrade plans.

Any perceived change in performance could be due to that compartment being a more rigid reinforced structure or different/shape volume. I could also be because of the seating and foam on top of factory location or possibly just my imagination. Maybe it's because that compartment has some venting that allows the air air to move whereas the original location is more sealed. I'm not an expert by any means, but having sealed sub inside a compartment without adequate venting seems like it would be less efficient.
Thank you - useful insight and agree: this stuff is complicated. I have seen multiple "experts" each arrive at different conclusions. 13.5JL - sweet! That will be an awesome upgrade. Separate amp or 5 channel?
 
I'm leaning towards the Rockord M5-1500x5 to power 4 of the interior speakers and the sub for the first phase, while still running 2 of the interior on the head unit amp. 2nd phase, I may replace the rear speakers on the swingback with either the Rocker 6.5 or 8" M2's. When i do that , I'll probably add a 4 channel amp that will run 2 channels bridged at around 200W for the those. I might add a DSP down the road as well.
 
That M5-1500x5 looks like a solid unit, especially for the price! I am concerned it would be a bit underpowered for the sub I am looking at (Kicker 51MWLE104 400/800w) with a focus of overcoming the engine/wind noise when cruising over 30mph. Gemini suggested RF M5.800x4 for the 6 speakers (the 4 interior would share 400w, while the rear 2 would get 400w - great for future upgrades & reasonable headroom), M2.500x1 for the sub for slight increase in cost. It also suggested the best power match would be the Kicker KMA600.6 for the speakers & KMA800.1 for the sub (at a lower cost). I like the idea of being able to wire each speaker with its own channel - though it's not clear to me yet if that is really a plus (but does deliver even power to each speaker), and lacks the upgrade path for the rear speakers. This could be solved with the Kicker 48KXMA800.4 - thus the same wiring as the RF. Who knew this audio stuff was so complicated!
 
The M5-1500 will push 600/w @ 2 ohms RMS which is exactly what the 13.5 JL is rated for. It'll do 400w @ 4 ohm which matches the Kicker sub you referenced. The KMA 800.1 and M2.500x1 are only going to do 300w @ 4 ohm. It's kind of a balancing act with these six speaker setups with balancing the power you want, ohm loads, and expense. I want to avoid running 2 pairs in parallel or series as one way puts it at 2ohm which most amps won't support bridged and the other way is 8 ohms which is going to lose efficiency. I also really want the flexibility of taking advantage of the PMX-8BB's 4 output zones to tailor the sound levels of each set of speakers and the 2 subs.
 
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