I played tuba for a while. I would get a 4/4 tuba. I played a used Mirafone 186 BBb but started on Conn 20J - also BBb. Wessex tubas look good. You did not state if your Jupiter was BBb or CC and whether it has three or four valves. It depends on what kind of playing you want to do. Do you have a lesson teacher? If so consult with them. Also check out the Tuba Forum http://forums.chisham.com/ for even more information.
Cerveny BBb Kaiser Tuba
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