Most Challenging CD

What is the CD that most puts your system to task in your collection?

My best is, Tchaikovsky "The Nutcracker," by the Kirov Orchestra, conducted by Valery Gergiev. This CD has it all, huge bass passages, giant crescendos, sharp horns and interwoven dynamics.

Yes, I know, there are lots of CDs that show all these attributes. There is one thing on this CD that I have never heard on any other, a real loud gun shot.

Sure, some 1812 Overture discs have real cannon fire. They just aren't as powerful as the gun shot on this Nutcracker disc. This report is a CRACKPOW!!!!!!!!

Ok, what do you have that tests your system like no other? I am not really interested in test discs. I have those and they aren't as good, besides being boring.