If you can live with 2 front speakers and 2 JL subs, a good 4-channel amp should suffice (phoenix gold, JL, a/d/s, etc.). If you want rear fill speakers then you'll need a 5 or 6-channel amp, plus you can't have JL stealth.
JL stealthboxes go in place of rear speakers (so you can't have rear with those), but you can still add a pair of mid speakers.
Stealthbox is a free-air type of sub and requires a lot of power to sound good, so you'll have to be picky about the amp. If you want 4 speakers then I'd recommond looking into a 5-channel amp (such as JL), or 6-channel amp (a/d/s P650).
I use a 5-channel amp (Alpine F450), to power 4 a/d/s speakers (front and rear) and a JL sub in a sealed box. I regret not buying a more powerful amp for this setup, but I'm satisfied with the current sound quality. The difference is night and day compared to stock or HK.
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