Quick Amp/Speaker question

[bpmbud]

Recently I found out my amps were overheating (ended up calling a buddy to check it out and noticed the protect lights going on during failure) and decided they were honestly cheap amps and it's time to upgrade anyway (Kind of a nice benefit of stuff breaking or not working properly i'd say) to something with better heat management and dissipation and am basically going off recommendations from you guys since you guys know what you are doing.

Anyways it looks like throughout the boat we have the Polk DB651's and I just wanna make sure if I were to replace one amp with the PPI 900.4 (cabin) and another with the Polk 5000.5 (tower and sub) that they'd be compatible and run properly. There are 6 in boat speakers and 4 tower speakers (Just trying to keep the system mid level not looking to blow out the entire lake... well, at least until the speakers blow then who knows).

Would this set up work compatability wise? Anyone with either of these amps have trouble with them overheating in the cubby during exteneded run time? Thanks again for all your help guys.

[Nitrousbird]

I would use the D5000.5 for the sub and in boats and the PPI for the tower. All will be fine I. The observer compartment. But if you are planning future upgrades I would go with two PPI 4 channel amps and a 2 or 1 channel matching PPI for the sub. Cost will be similar, more power and more flexible for future upgrades.

This is coming from someone who had a D4000.4 and D5000.5. I only did the 5 channel as I planned all my system together and have no future upgrade needs so it matched well with my needs.

[bpmbud]

Which PPI would I be looking for for the sub?