well, in my search for a second headphone, a backup, or compliment to the 225 or the ms1, i can cross of my list the senn hd518.
while not really bad, theses cans, well, sounded like cans. no immediacy, no "shine"
i hate to say it, because i really wanted to like them, but i know what folks mean about the sennheiser veil.
i'm sure this isn't true of all senns.
i liked the ad300, which is a discontinued model, that cost less than half of the 518's.
since i fill the need to have 2 headphones, it could be the 225 and ms1, or a different grado
i might be ruined for all the others !
one caveat, this is just based on the first hour or so listening, the 518 may benefit from some time to break in.
also, the 518 does sound really good on certain recordings, just not all
Have you had the chance to try the HD558 or 598? Cause the HD518 is just boomy and not very good in my opinion and lack depth in various ways. (including comfort too)
But won't push them, since it may be the case that you definitely love the exciting grado sound (these are not exciting, but smooth and relaxed) but they do make nice compliments, and i suggest you try them when you get a chance to (and HD650 too, or as many as possible lol)