hispls 5,000+ posts
CarAudio.com Veteran
I got into LTO several years ago so I couldn't say what's a deal right now but I used to always just get the "premium" parts store AGMs. Batteries Plus stores used to sell Duracell branded AGMs that were a decent value, those were the last AGMs I bought but it has been a while.What would be a good battery? Preferably a big enough one so that I don't have to buy two
The point with a parts store battery is that they're really easy to swap out if you kill it under warranty. I would not expect any single standard sized automotive battery to really hang with that amp. One is better than none but your voltage may still sag unacceptably low if you push things.
You've got some good answers here so far.