Which power amp?
 

I have two harbinger dual 15" speakers, and need a power amp. I have looked at a few but dont know much about the whole thing so any advice would be good. The ones I have seen so far are the QSC 1450 and the Beringer EP2500

You need to find out what each speaker's watts RMS is, and also how many OHMS. (resistance). Knowing the peak watts isn't a bad idea, but the watts RMS is important.

When you have that information, you'll be able to make an informed decision on which amplifier will actually be right for the speakers.

First of all, What is your application? PA subs? Probably. Is it a bandpass box or a conventional cabinet(s)? My own personal experience has been that only the very top of the line that Behringer makes is worth owning. I've never had any problems w/ QSC.
Verdical is right you better know what your speakers power handling requirements are or you won't be using your power amp for very long.

15" speakers !!!
amazing
I wish I could have a pair

I wish I could afford the level of amplification it takes to make them sound decent.

Have anyone of you ever heard of JBL?

I'm listening to music on a pair of JBL's right now.

Goddammit I'm sick of taking the time to help these people and they turn out to be a one-post-wonder and you never hear from them again.

The least a person can do is update on how things went so others can possibly learn without having to post a thread just like this one.