I'm looking for a new amp to power my pair of Norh 4.0s. I do mostly mp3 listening off my computer. Right now, I'm using this as an amp. My friend had an extra one lying around, which is why I'm using it (Of course, he wants it back soon) I'm also planning on replacing the sub with a more powerful one (looking at a svs pci+ or hsu), which means I'll need a new amp anyways. I'm looking at a price range of $200-$300. I really don't need a receiver, since they are going to be connected to the PC. The mono amps Norh sells are a little pricey for me. Should I look at stereo amplifiers such as the ones NAD sells, or would a good used one suffice? I'm not sure how the Klipsch amp compares in quality to one of these. What amps could one suggest for me to use in this situation?