Posted by Rob P-M on July 26, 2002 at 12:46:58:
In Reply to: Re: King rotary valve tubas? posted by js on July 26, 2002 at 09:23:24:
The rotary horns came in two sizes: one pretty much equivilent to the pistory horns ('687" bore) and the large bore version (.750" bore). Typically King horns with the .687 bore and a removable bell have a 6-1/4" bore at the bell joint; the .750 bore horns have a 7-1/8" bore at the bell joint.
In an early 30's King brochure I have, there is an explicit statement that the Symphony Recording Basses (1240/1241) are available in both .687 and .750 bore.
In the 1938 King catalog, which does not show the smaller rotary version of the symphony bass, it does show the orchestra pit bass with medium bore (.687) and says it is available in large bore (.750). The same catalog shows upright (fixed bell) #1285/1286 and recording (removable bell) #1290/1291 large bore rotary basses.