I recently received a pair of R50s as a gift but don't have a means of powering them. I want to use them strictly for music so I was considering running either SPDIF or lineout/headphone out from my laptop. To complicate matters I'm on a college budget, ~$100 so I think my options are severely limited. I have no problem going either refurbished or used, but don't know what I should look at. I've heard basic amp, given my intended use, is the way to go. Would something like this be too weak? Can anyone recommend anything?