Stereo System Sucking alot of juice

[SargAdam]

Just wanna throw this out there and see what people think. I have the Roswell Quad Spin Pros with the Roswell 500 Watt amp on them. I also have the factory in boat speakers and a 10 inch sub with a 500.4 watt on them. When I cruise across the lake my volt meter drops everytime my sub hits. Im thinking its because its not wired to the secondary battery. Also thinking about putting an isolator on the 2nd battery to keep it charged all the time. Ideas would be appreciated. Thanks guys!

[Rharness]

i have 1 battery for sound system and 1 for starting boat. that away i never have a dead boat. i have 3 amps. kicker 400x1 on sub, punch 400x4 running 6 inboat speakers, punch 250x2 running my tower speakers. played for 4 hours without ever starting boat.

[gride]

I did some reading on alternators last night. There is a plethora of knowledge out there that can help you understand alternators more. I was surprised to learn how not that many amp hours require a higher output unit than most boats come equipped with it seems. Also, it seems there are units that output their stated voltage continuously rather than approximately 40% less than the peak output that amany units typically produce.