Ok, my system isn't approaching the level of most on here, but it's a fairly respectable setup with some decent components. My old speakers were well out of their depth and masked a great deal of my systems potential.
Now my new speakers (albeit in temporary enclosures) are in the system I have found a couple of discs that are almost un listenable, be it due to the recording quality or terrible mastering.
Just put this on...
Dip in and out HERE