just bought these AKG K242 (not the current HD version, but the vintage ones, from the 70s or the 80s, don't know for sure).
Now, they sound too good to be true. I don't know their history with previous owners, but I begun to suspect that someone made some tweaks to them. I also own Sennheiser 555 and 595, but this AKGs seem to be in an entirely different league. The bass is so powerful that I'm afraid to listen to them, so that I won't damage somehow my hearing! And I'm not kidding! It's like I have full size full-range speakers on my ears!