Here's my setup, what should I upgrade?

[rjonesy]

I can figure out pretty much any DIY stuff except Audio, I just don't get it, so I'll do my best to outline my exact setup and hopefully yall have ideas.

All factory 2005 VLX except for the head unit. Factory 6.5" bullet cans on factory Illusion tower. We surf, swim, and cruise. Don't listen to rap anymore. Just a boring 35 yo with 2 small kids.  One speaker has died, and the other 5 sound okay-ish. I'm just looking for clearer and louder.

Head Unit: Sony DSX-M80, usually playing iPhone via USB (45w RMS, 100w Peak)

Amp: Factory Kicker ZX 350.4 (60w RMS x 4 channels)

Speakers: Factory 6x 6" Kicker 05DSM60 (50w RMS, 100w Peak)

It sure seems like 15 yr old speakers are the weak link. Looking to spend $500. I'm handy enough to cut the 6" holes to 6.5" or 8" if that's needed.

Edited July 19, 2022 by rjonesy

[MLA]

So the quantity of 6 speakers is 6 total? 4 in the boat and 2 on tower? 

Rather then swap the existing 6" in the tower pods, id suggest upgrading to an 8" set. This will improve both volume and sound quality. To ease the budget, you could repurpose the current 4 chnl and bridge it to two chnls for 175 to each new 8". If the budget permits, I would get rid of that old class-A/B car amp in favor of a new class-D marine amp. 

If the boat has only one pair in the cabin and one pair in the bow, I would suggest adding a 2nd pair to the cabin. More speaker is a much more efficient way to increase volume v's adding more wattage. However, this would require an external amp to power all six. A 4 channel is a perfect amp for this. 

Another way to get more volume out of a speaker, is to limit its band width. Enable the hi-pass filter will eliminate the frequencies below the level you set, thus reducing the stress on the speaker and amp. You can then drive them a little harder. Downside is, you eliminate the bass. Thats ok, because, those speakers do not like reproducing those low ranges anyway. So consider a small, mild woofer for overall better sound quality.