I am looking into getting a nice pair of headphones (looking at a pair of Koss) to listen to music and watch movies on a MacBook pro. From what I understand, a pair of headphones like that need more power than a laptop provides to really get strong bass and experience high quality audio that the headphones are designed for. Does anyone have any experience with headphone amps? I have come across a few on Amazon, but was hoping to get someone to give me their story with them. I have looked into the Rolls HA43, and that right now seems like the best choice. It doesn't need to be mobile, just something I can plug into at my desk.