Reply to Setting up new speakers with or without amplifier.

Hey, I have been doing some searh on good speakers for room dj'ing and ended up with CELESTION KR2.
The question is will I need an amplifier to get them working properly? I dont really know much about these kind of stuff now.
I got Z2 and will I be able to connect those two to my Z2 soundcard?
Will it work like an amplifier?
Anyways, how important is amplifier?

I got this old yamaha subwoofer, but no good speakers to test it out how good it is, cus of the connections inputs which differs on left and right speakers and not sure if I'll be albe to connect those two speakers, or will I? Thanks!
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