Posted by Steve Marcus on April 18, 1999 at 23:28:30:
In Reply to: Re: older Wm. Bell tuba posted by Joe on April 18, 1999 at 15:03:43:
Joe referred to:
"The Conn 20J 6/4 size BBb with a 20" upright bell and huge body."
According to the 1967 Conn catalog that I have, this was their model designation for their large BBb tubas:
20J: Forward 24" bell, 3 valves
21J: Upright 24" bell, 3 valves
24J: Forward 24" bell, 4 valves
25J: Upright 24" bell, 4 valves