If you liked the 57’s then you definitely want to consider phones with a planar magnetic driver. Unfortunately, the price of entry is a little higher. But if you want to try out a vintage planar magnetic (Orthodynamic) for (usually) under $200, keep an eye out on eBay for the Yamaha HP-1 (or YH-1) HP-2 (or YH-2) or (the most expensive) HP-100. I have all three and they beat all my other phones except the fabulous Denon AH-D7000 (which has a regular dynamic driver) -- no longer in production, but worth looking for.
The only caveat with the Yamahas, is they need a bit more power than most (but that’s also true of the new planar magnetics as well.) Here are a couple of links to get you started:
http://www.innerfidelity.com/content/how-planar-magnetic-headphones-work#1o0rS1YKav6iD0y6.97
http://www.head-fi.org/t/111193/orthodynamic-roundup
The only caveat with the Yamahas, is they need a bit more power than most (but that’s also true of the new planar magnetics as well.) Here are a couple of links to get you started:
http://www.innerfidelity.com/content/how-planar-magnetic-headphones-work#1o0rS1YKav6iD0y6.97
http://www.head-fi.org/t/111193/orthodynamic-roundup