I have just recently gotten into the love of good audio. I will admit I know nothing about all of the tech that goes into it. I am considering purchasing sennheiser hd595's and a headphone amp/dac. I've heard that going from a headphone jack is worthless and was just wondering if you can plug the Zune USB chord directly into the USB port on the DAC/headphone amp or if there is a product that you can attach to the port at the bottom? In other words what all do i need to have the headphones and amp work to their best abilities. any advice would be great. If i'm an idiot and everything above is wrong feel free to say so but please inform me of what i should do. thanks in advance for the help.