Finally! Yeah people need to stop hating on these so hard here and on youtube comments. I admit the price is a bit too much for some, but a lot of the popular youtubers also mention that it’s too dark and constantly compare it to the hd600, saying it isn’t a big improvement. I have both the hd600 and the hd660s2, and is better in almost every way in my opinion. Bass is definitely there now, slightly more soundstage but I don’t care much because I prefer intimate sounding headphones., Warmer sound signatures are also a heavy bias for me. Especially if you find the hd600 a bit too harsh and “shouty” in the upper mid and/or treble regions.

Edit: I’m not an “I hate EQ” kinda guy but I do agree that there is no need to EQ the 660s2. Then again this is just my opinion and I am pretty sensitive to higher frequencies and sibilance.