TubaForum.net

Worth a look.
https://www.ebay.com/itm/226288382306? ... media=COPY

These are good tubas; I don't care what anyone says.
I've only played a couple of YBB-641 tubas, but like how they play. The top space G in the staff is very sharp, but you can play it 3rd valve or just do a long pull on the 1rst slide playing it 1+2. Otherwise, I find this model to play well in tune with a nice response and sound through all registers.

2nd valve is a better alternative for high G