I'm new to the world of "audiophilia" and I was wondering what you guys thought would be a good portable amp to use with my HD-598s? I don't really know anything in terms of power and the science/physics behind the generation of sound that I am looking for so I was wondering if you guys could help me out. Right now, I plug these headphones into my HP laptop and my Zune HD, but mostly use the laptop. I was looking at the PA2V2 and was wondering about that, but I honestly don't even know where to start. Any help would be greatly appreciated. Thanks guys.