jeffc:

First of all, you're not getting great sound to begin with with MP3
and your
laptop.

True

Second, I don't really think they're great headphones.

There's lots worse!

I'd
recommend going to a high end stereo store near you and ask to listen
to one
of their best stereos. Tell them what kind of music you like. That'll
give
you some idea of a reference.

Probably false. The rooms tend to suck; many current high end speakers
like Thiel, McIntosh, Legacy, are notorious for golden showering the
dynamic overlay of the soundstage, and they like to use musical
selections that are almost tailored to hide the flaws of what they
front (because they sure don't represent!). All that aside, headphones
are not supposed to sound like far field music reproduction. Compare
headphones to headphones, ideally with binaural source: compare
nearfield to nearfield and compare full field to full field. Don't mix
your mismetaphors.

For audiophiles, Stax has always been the preferred headphone, compare
it to them. Find out what they used in the studios when they made your
favorite rock records, if you're a rock fan, and audition that too.
Find out what the US Navy issues submariners for sonar duty, audition
those too.