| I have several pairs of At 40m s and recently bought the 50 s on recommendations.
The original 40s are very very good consistent cans - very comfortable / good isolation / very good sound right off the bat with experienced clients commenting on how much they liked them . I subsequently bought a newer pair which turned out to be guite middly and requiring a lot of use to wear in; they now sound pretty good.
The 50s on the other hand whilst having very good isolation and bass that goes right down, are to my ears too kind in the mids and thus fairly unrevealing, they are also uncomfortable relative to the 40s. It may be they'll wear in who knows.
I haven't tried the 280s etc but my experience with the rest of the Sennheiser line points to the 40s possibly being the better can.
You need to try them and compare. Hope this helps.
Cheers, Ross |