looking for amp for my center channel(under $100)
 

I'm lucky enought to have a QSC theater 2 channel amp my friend gave me. Now i would like a 1 channel to improve my center channel. I f possible a 3 channel would be great so i could power my center as well as my subs.
FYI, i have the amp connected to the speaker L/R output on my receiver, and the speakers connected to the amp. Just wires, not using any plugs of any sort. Thanks for any info.