Stereo Upgrade - Amp & Sub: SubWoofer Design & Installation

SeadooRXGuy - thank you for all this additional information, details and links - VERY helpful!
 
I installed a Rockford Fosgate powered sub five years ago and it’s still kicking it out. The advantage of a powered sub is that it’s easier to get power to it using a direct connection to your battery and you just tap into one speaker wire for the sound. This eliminates having to run wires to the helm.
 
I installed a Rockford Fosgate powered sub five years ago and it’s still kicking it out. The advantage of a powered sub is that it’s easier to get power to it using a direct connection to your battery and you just tap into one speaker wire for the sound. This eliminates having to run wires to the helm.
Nice! Did you have a custom enclosure built?
 
Nice! Did you have a custom enclosure built?
The unit comes in its own box and I just placed it in my port cabinet. It could go pretty much anywhere there’s room. This is not a “marine” unit but I’ve had no issues.
 

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So i have been doing more research.. So I have the Kicker KMC100 head unit.. first off.. I noticed (I can't remember if its the Balance or the Fade does not work right.. ) I will rotate it to to one side and the sound goes out. instead of left/right or front/back. I assume something is wired wrong.. the previous owner had the helm replaced and the head unit. So maybe they wired it wrong... (I should bring the boat in and have it looked at..) How does others work?

Upon reading the manual for the KMC100. it has a 6ch amplifier. it also has a zone 2 output. Shouldn't Zone 2 be used for the Switchback speakers? then the other 4 connected normally? I also see a subwoofer output. i assume that goes to my subwoofer with it own amp. But having said that, here are 8 RCA outputs. 2 for front, 2 for rear, 2 for zone 2 and 2 for subwoofer.. there are also wired outputs front left and right, rear left and right and zone 2. Whats the difference between the wires and the RCA?
it seems like the head unit puts out 25W for the 6 channels.
Would I add another 6ch amp to run the 6 speakers? and then another amplifier to run the Subwoofer? How does this all get connected?

Also, do these boats have an antenna? to pick up radio stations?
 
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So i have been doing more research.. So I have the Kicker KMC5 head unit.. first off.. I noticed (I can't remember if its the Balance or the Fade does not work right.. ) I will rotate it to to one side and the sound goes out. instead of left/right or front/back. I assume something is wired wrong.. the previous owner had the helm replaced and the head unit. So maybe they wired it wrong... (I should bring the boat in and have it looked at..) How does others work? Upon reading the manual for the KMC5. it has a 6ch amplifier. it also has a zone 2 output. Shouldn't Zone 2 be used for the Switchback speakers? then the other 4 connected normally? I also see a subwoofer output. i assume that goes to my subwoofer with it own amp. But having said that, here are 8 RCA outputs. 2 for front, 2 for rear, 2 for zone 2 and 2 for subwoofer.. there are also wired outputs front left and right, rear left and right and zone 2. Whats the difference between the wires and the RCA? it seems like the head unit puts out 25W for the 6 channels. Would I add another 6ch amp to run the 6 speakers? and then another amplifier to run the Subwoofer? How does this all get connected? Also, do these boats have an antenna? to pick up radio stations?
If you can wait 9 days till I’m in front of a computer I can break down all of this. Even the boats with the 10k Roswell setups are wired incorrectly. Bennington is not an audio shop. Neither are the marinas. I’ll explain how to right the wrongs. I think I touched on it in earlier posts. They group all the speakers together under the helm. 25w per speaker is not enough for any time of sound quality or bass.
 
yes I can wait, i am still trying to find someone to do the work here in Wi..... but I want to be ahead of the game...
 
A audio shop can fix this without an issue. Just gotta find one that can accommodate a boat on a trailer. Or would go to where you are docked
 
This is what's coming out. Is it simply connecting the rca cables front/rear/zone 2 to to a amp or amps and the connect the 6 speakers to the amp? Similar for the sub.

Is there power under the helm for these amps? Or do i need to run seperate power cable? Will that be difficult? Plus running the speakers wire to the sub in the Switchback seating...
 

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Is there power under the helm for these amps?
Typically not. I had to have some electrical work done a few years ago, and since they had to remove underskirting anyway, paid to have an extra power line ran to my helm to have the option to add on down the road. Long story short, you’d need to run the power to the helm if you want to put a new amp in there.
 

I am still learning here - this is my current knowledge base:

I understand the 5 channel has the amp power for a non-powered subwoofer, so the extra amp is not required (pending power needs). The further advantage is that these smart amps can help tune / balance the speakers and amp. Vs adding a second amp for just the Woofer. The Fosgate M2 is their top of the line and unit I am looking at. However, you don't have to use the 5th channel, which I believe gives more power to the speakers, and / or better heat diffusion, which is important if you are in hot climates (my lake hits a 120). There are some 6 and 8 channel amps, but they get pricey.

I find the choice of sub much more difficult. The "normal" speaker woofers require a sealed compartment behind the speaker, again as I understand it (some are vented, some are not, but you need the space to optimize performance). So the better option is then (if you don't want to dedicate an entire section of storage and get it sealed) a pre-configured or custom box. Not a lot of marine box woofers - Kicker Tube or JL Stowaway seem to the be two choices that are reasonably sized. If your have room for a larger box and not worried about stuff damaging the speaker, then there are more options. I have not been able to find a single installation of the JL Stowaway in a pontoon, which I really like (downfire, protective shell, perfect for the forward driver corner of the SB?), also lots of good reviews for the Kicker Tube. Many suggest a marine box is not needed, but with kids and LOTS of grear and monsoons - everything get's wet in my Benny. The Garmin site for JL specs is completely wrong - Crutchfield list stowaway boxes at 18x7x13 (10") 22x8x15 (12"). Vs the Kicker Tube at 9x14 (8") 11x17 (10").

I would definitely get Crutchfield involved. And Rockford Fosgate, to help design the system.

SEE POST 2 ABOVE, SeadooRXGuy has some great insight and advice! Though I have read a lot of feedback that the stock speakers work great with an added Amp - he feels NOPE - just dive in and do it right (which is generally the best advice).

My next step is to start with the JL Stowaway Sub, add the Fosgate M2 750 amp, and talk with a pontoon installation specialist, or 3. I may even wait until next season and hit the sandbar and start up some conversations.
 
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So doing some more thinking.. I am wondering if i just keep the amp i have and buy 2 new 4 ohm subs. Run them in parrallel.. Possible 10" or 8". Whatever fits and be done. My current amp will drive 400w at 2 ohms..
 
Why not buy one 2 ohm sub and drive it with 400w? 2 subs will split that to 200w each. More wiring less space and you can probably get as good or better results with a single.
 
Maybe.. I guess I was thinking 1 in the front of the boat and 1 in the rear. Then the bass would fill the front and back. But maybe 1 would work.. if I do 1, I could choose 2 ohm or 4... maybe 4 would be better to reduce the power... if I do 1, then a 10" should fit under the rear seat. If i do 2, then I need a 8" in the front and then I would just do a 8" in the rear..

Anyone do 1 vs 2?
 
It's all what you prefer most. With low frequency sound being less directional and focalized, the filling in part wouldn't be an issue to me. Depending on what and how you listen to music there could be merits to going with 2 8s. If I were on the fence, I'd look for shop where I could compare the difference in the two with the music I'm most likely to listen to.
 
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