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Finally getting around to cleaning up the inside of this tuba. Pretty pleased with these. This is the .750" bore variant, too. I wonder how many of these horns still exist?

Those look good. Was the 3/4 inch bore model still called a 1240?

bloke wrote: ↑Sat Nov 18, 2023 7:34 pm Those look good. Was the 3/4 inch bore model still called a 1240?

I think so, but I wish I knew for certain. I can't find anything about this bore size in any HN White catalogs of that era that I've found online. It's the same bore as the "monster" rotary B-flats.

@arpthark @bloke It looks to me like they were called the same thing regardless of bore.

Try page 59 here:

It talks about "King Symphony Model BBb Bass". In the specs (lower left) it lists the bore as .687 (bit fuzzy to see). Then at the bottom of that paragraph it says "Large Bore .750"

https://www.saxophone.org/museum/publications/id/80

In another post in Repairs you mentioned that the intonation isn't as good as the 689 bore horns. If we assume they used the same big parts for the 689 and 750 horns, the 689 horns have a .750 bore at the big end of the main slide. So with a 750 bore horn, things would have to be cylindrical from the valves through the main slide, or they'd have to have a slower taper through the dog leg and maybe smallest bow. Either way, the taper of the small parts of the bugle are different that the 687/9 bore instruments...

King innate intonation is pretty good, but far from perfect. The 11/16" bore instruments are really easy to manipulate/lip, and I suspect that the 3/4" bore instruments are going to be a little bit more difficult, in that regard.(??)