Bonanza got it right, in one episode, when Ben Cartwright was carrying a helicon out of his bedroom. It looked a little dark and beaten up, but, I would imagine that houses got a little smoky on cold days in the 1870s.
The Music Man (in both the Robert Preston and Matthew Broderick versions) had the band with bell-front sousaphones. It was supposed to have been about the same time as Hello Dolly. The latter version added insult by having the 2000-ish style color guard girls twirling U.S. flags around.
Brassed Off, a more contemporary film, showed the tuba players in the brass band walking to rehearsal, carrying front action valved tubas (one with rotary valves). When we later saw the band in rehearsal, they were playing the usual top action valved tubas normally seen in British brass bands.
Maybe you can think of other movies which correctly or incorrectly use tubas.
I can think of many movies in which the tuba had a great leading role:
• Mr. Deeds Goes to Town
• Still Breathing
• My Girl
• The Stars and Stripes Forever (maybe the story was a little off, but they got the sousaphone correct)
