I think you'd be surprised at how much difference you can hear with the SR-60 or -80s and other 'phones of the same price -- both are under $100. You're not the only one with bad ears -- try a couple of decades mixing live PA. ;)

On the price/quality front, Grado is so far ahead of everyone else that it isn't even funny. The SR-80s often rank higher for sound quality than the Senn HD-280s, which cost two to three times as much.

Of course, Grado sells expensive phones -- the RS-1s aren't cheap in anyone's book. But I urge anyone who really enjoys music to try the SR-80s or SR-125s with a good input source. The difference in clarity is amazing.

If you insist on isolation, the ne plus ultra of the line would be the Etymotic ER-4P. However, one warning with them -- the drivers are very sensitive and stable, and they can reach ear destroying levels. The ER-4S isn't useful in portables, it needs an external amp (it's built as an in-ear stage monitor)

 I'd get the ER-6 instead -- you don't need high gain when you're wearing isolaters, and the ER-6i has both that and the white "I've an iPod, mug me" cords, if you live in an area with that problem.