These cans are really, really good. Highly recommended.

I bought the HD 681 F for a super cheap price and they are totally worth it. Sonic-wise they are on the brighter and leaner side for sure, which you may or may not like. A little burn-in helped taming the higher frequecies. They are quit resolving throughout the entire band, vocals are quit forward but a little thin, especially male vocals. The bass is not that hard hitting and on the leaner side of things but quit e textured. Comfort is a hit or miss though, because they are quit big, but still smaller than the HD 681 Evo. You can swap the stock pads with the AKG velour pads or even the beyerdynamic pads or the HiFiMAN pads. They fit very well and add comfort and help with the soundstage alot because of the increased distance from the ears to the drivers.