depends on your taste, I like the DT 990 more for classical and the Pro 250 Ohm model is
http://www.amazon.com/Beyerdynamic-DT-990-Pro-250-Professional-Acoustically-Applications/dp/B0011UB9CQ
$145 on amazon RIGHT NOW, thgouh the DT 990 is a little more fun than the dt 880, meaning the 990 has a touch more Highs and Bass, the Schiit Vali REALLY does a nice job of balancing the headphone out!
But PURELY for classical the DT 990 is one of my favorites, how ever on the off chance you want to listen to a Classical Duet, say... Piano and Cello, then DT 880 might handle that better due to a smidge less bass. But, that "fun" sound of the DT 990, or the extra bass and highs, is nice for classical! Makes the crenshendo's really ATTACK, the extra energy in the high notes and heft of the bass is super nice, and yes the mids on the dt 990 are wonderful too! I found them to be very delicate, just the sound of the dt 990 really fits the mood of classical for me, the drastic change in pace, the shift from quiet to LOUD, gentle and delicate to POWERFUL AND SWEEPING. Both the DT 880 and 990 are good for classical
how ever if you happen to like jazz and classical, then the DT 880 is the way to go, as imo the DT 990 had to much bass for Jazz