I did this work a couple years ago, and if memory serves it called for ophecliede and bombardon. There are two separate parts, but both are not playing at the same time. There isn't a lot to the parts, but there is one exposed section. I played both parts on F, switching back and forth as needed.
I performed this work in the spring of either 1997 or 1998 in Oklahoma City. The story I recall is that the score was recently rediscovered while a church was being renovated...probably BS, but fun none-the-less. I believe Tim is correct about the 2 parts. Each rehearsal, the conductor kept adding short solos to my part...I believe I had an ophecleide part, with added serpent solos. I performed it on my Alex CC, but with each added solo, I recall wishing I had an F tuba at the time...not rediculously high, just a couple touchy solos. Enjoy!! jobey