generic power ratings are no way to specify equipment, and no way to choose a sub or amp.
1200w what?
If you're looking at peak ratings they're absolutely meaningless.
Only RMS ratings are of value - and a lot of the low price brands lie about those too.

For example - Pyle has a 12" sub that's "1200w" peak, RMS of 250w...It's $44.
Rockford Fosgate has the T2 12" with an RMS rating of 1200w...It's around $500.

FWIW - there are many 300-500w rms subs that are capable of a lot of output. For a pair you'd want an amp that's 600-1000w rms. But there are impedance/voice coil variances that have to be accounted for in choosing.

It will be easier to offer you specific help if you find a couple examples of subs you're interested in, then ask about the type of amp that would power them the best.

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The audio is for an online stream

With a pair of 2000w rms subs you'd need an amp capable of 4kw to get optimal output from them.
However -- there are a lot of things to take into consideration here.
For one, 4000w rms is a TON of power and will require a TON of current, not to mention a very expensive amp (or pair of amps).
There is no stock electrical system that can handle that kind of current demand w/o being severely stressed, which usually results in a blown alternator.
Those subs should perform quite well with 1000w rms or so, so you don't NEED 4kw for them to play stupid loud.

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