need some stereo system advise

I want some unbiased advise and tips if possible SO i have a 1500w mtx thunder amp, with 2 alpine type r's. I never really have it on max for continuous periods of time not even a whole song, because i'm over cautious about my bat. and alt. My battery died a couple weeks ago...and i would have someone jump it then i would drive 10 feet and the car would just shut off...i was hopin it wasnt my alt. i had a brand new bat one at my house so i just threw that one in. It's just a regular bat. and it fixed the problem. But i'm worried about doing the same to this one. Do i really need to upgrade my alt. when i only have 2 10" subs? Should i do the big 3? What about new batteries? Yellowtop? Correct me if i'm wrong but if i put a battery in the back right now, let's say redtop, my alt would have to charge both batteries thus being harder on the alt?   What is some advise guys? New Bat? New alt? even though on average i'm pushing 1000w max...have gains and doodie turned pretty far down. Thanks for any help! MikeHello.

What vehicle?  Not many vehicles can support an additional 1000W load with the stock alternator.  Upgrade the alt, and the Big 3.Support the12volt.com

a new alt would be nice abd since you're not running a whole lot of power you might only need a 150 amp alt. your stock alt is probably more like 80 or 90 amps