In August of 1989, Phantom Regiment's horn-line joined the Kansas City Symphony Orchestra for an encore performance of Wagner's "Elsa's Procession to the Cathedral"

http://www.youtube.com/watch?v=Tbw3VXneGso

The orchestra's conductor had told the brass line during rehearsal to "go ahead and play loud." Heh. Whoops. Probably what was Phantom's best horn-line ever unleashed full outdoor volume in the concert hall.

The build-up takes a while, but is worth it. The orchestra is pretty much irrelevant by 5:45.

That's very cool! By the way, you can go up to the iTunes store and find an unbelievable recording of Elsas (transcription) on the Retrospective album played by the US Marine Band and Colonel Timothy Foley. They play from the beautifully sublime to the final bars where the brass seem to have no limit to their capacity for hairy chested power.