Back on the 6XX and 58X comparison, if you find the 6XX mids too forward the 58X might work for you as I find their mid presentation slightly less forward than the 6XX. The 58X has a more intimate soundstage but much better instrument separation. I don't ever notice the "grain" in the 58X and I think I've only heard it when concentrating very hard and listening for it...though I may have imagined it. The bass and subbass on the 58X is infinitely better and more extended than the 6XX. I also found the 58X more resolving and responsive than the 6XX which some find too "smooth" (I actually like the smoothness). I really liked the 6XX but I prefer the 58X which I now listen with almost exclusively. Works great on my Woo Audio WA7 Fireflies DAC/amp.