As asked, for those of you who have modified your HE-6, what one mod. has the biggest impact in sound quality? I have heard a new cable or hard wired but have not done it to mine. I have done the grill and felt mods and earpads.(still waiting to get Audeze Micro). I think the grill mod has had the biggest improvement from the stock pair. It really opens up the sound. Unless you hardwire your pair, all the other mods are reversible.