Posted by Lew on February 13, 2002 at 22:42:26:
In Reply to: York BBb posted by Steve Clark on February 13, 2002 at 21:27:36:
The variation in how the 3/4, 4/4, etc classifcations are used makes them not particularly meaningful or useful. In general as you move from 3/4 to 6/4 the tubas get taller, heavier, and have larger branches and bows, but there are tubas that are considered 4/4 sized that are as large as other manufacturer's 5/4 sized horns.
In my opinion all that really matters is how well a particular horn works for the purpose for which it is being used. I have a light weight horn that I use when I need to be standing for a while, a large horn for outdoor concerts, a "full" sized horn for indoors seated concerts and for small ensembles. I can get more sound out of one of my smaller horns than I can out of one of my larger horns. I don't worry about which is a 4/4 or 5/4, just which one works for me.
I would classify your tuba, without seeing it, as 5/4 sized. That is based on the height, which at 38-1/2", is relatively short (assuming that height includes the bell). York made a "Monster" bass that was 58-5/8" tall and their standard bass was 45". I am also assuming that this has large branches and bows. If the branches are smaller this might even be a 4/4 size. Bore has less to do with the size classification than the other dimensions.
As for your receiver, York apparently used very large shanks for their tubas. Joe S. #2 who posts here has a York "Monster," that's clearly a 6/4, that has the same very large shank. This isn't really a determination of size classification.