I have 2X POLK DXI 12" DVC subs
Those are 4 ohm DVC subs, so your wiring options are either 1 ohm or 4 ohm. You are going to need a mono amp thats 1 ohm stable or will deliver the needed power @ 4 ohm. I would suggest running at 4 ohm as opposed to 1 ohm. You will need to shoot for between 600W rms and 1000W rms for that pair.
I have 2X Kicker DX400.4 amps (car audio)
Im not sure what amps are currently driving your in-boats, but with these amps, you are not likely to hear an audible difference in volume out of the in-boats or towers. You will need to either double the number of speakers or double the wattage to them. Changing speakers will certainly change how it sounds, as each speaker designer has their own sound signature. Only your ears will determine if its an improvement or not.
12" kicker sub. Of course the sub is not build into an enclosure, but just into the cockpit kickboard, free air into the front seating area.
Build a 1.0 ft3 enclosure, feed it a solid 400-500 watts rms and you would not know it was the same sub. One sub done correctly will trump 2 in a compromised enclosure. So giving those 2 12" polks ample volume is important.
The stereo sounds very mediocre, is under powered
Not uncommon at all for a manufacturer to use quality gear, but typically poorly tuned and minimum amperage to the speakers.
do you think replacing and or adding to the factory amps with the 2 kicker amps above will do the trick to power the polk subs and the polk coax speakers throughout the boat?
Hard to answer without knowing exactly what amps you have and how many speakers.
if you are going to expand the existing house bank, I would suggest installing 2 new matching batteries as opposed to just wiring a new one in parallel to an older used battery. It will greatly reduce its life and performance. If your plan is to spend time playing the system at anchor, it might be worth looking into using a shore charger to replenish that house bank and not rely on the alternator.
Last edited by Wylietunes; 01-15-2014 at 04:17 PM.
Michael
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