It's very flexible and diverse, though the instrumentation on first glance you wouldn't necessarily see it as such. The tenor saxophone and trombone have always had a nice timbre blend. Ryan is one of the best musicians I know. He's one of these guys that, for reasons I can't quite figure out, doesn't get nearly enough recognition. Maybe part of it is that almost nobody plays the bass trumpet now.
People are confused, almost, because the range of the instrument is lower.
It's sort of in the range of a trombone, but it doesn't exactly sound like a trombone, and he really doesn't approach it the way most bass trumpet players or valve trombone players do. Valve-trombone is a similar instrument. I've known Ryan for about 20 years. Most of the guys I play with I've dealt with at one level or another for quite awhile. He gets his own sound on the horn.