Hey everyone, I'm looking for an amplifier to power my Senn HD580's. I would like to keep the price under $150 if it's possible. It doesn't really matter to me if the amp is portable or not, I'll be using it at my desk. I would like to have one with a built in DAC, but it isn't a huge deal to me if it doesn't have one. Having a portable amp would be nice though, right now I'm using a dinky Fiio E6. I mainly listen to Metal (Emmure, The Devil Wears, Prada, Like Moths To Flames....) and Dubstep/technoey stuff. I hope this is enough information for you guys, and I hope I get some responses! Thanks in advance!