So at the end of this month I'm going to buy a beyerdynamic a20 amp to use with my hd700 headphones, and I was wondering how much of a limiting factor my custom PC would be. So I've got enough money to buy a good external dad of needs be but I was wondering about using my xonar Phoebus sound card and buying a converter for 3.5 to rca. Would this be a degrading sound experience ? Or is it super worth the money getting a good dac? Problem is I tested the a20 on an Astell and kern ak380 so I don't know how different it would be. Thanks