the HD580's are 300ohm right? while the PK-1's are 150 so i figured the PK-1's would of been the best option.
anyways i recieved the PK-1's the other day and i'm fairly ecstatic about them. I prefer them much over the AKG K81's except on occasion when I just need some BIG SLOPPY bass... the PK-1's resolution/sound is really mind boggling. I thought maybe i was too sold on all the positive reviews and it was possibly some kind of placebo affect but after A/B them with my other headphones (PX100, Sony V6, AKG K81, Marshmallow, MX400) the resolution/detail is outstanding.