Lee Stofer wrote:I'll just add one more comment to answer Mike Milnarik's comment.
Although Rudi has not made a true 3/4 piston-valve CC tuba, he has made a truly fine mid-sized piston CC, called the model 4345 piston CC tuba. Herr Meinl & son seemed dissatisfied with the Perantucci model piston CC tuba they had been commissioned to make in the latter 1980's, a copy of an old Conn CC. It was a very true copy of the old Conn, but not exactly what modern players were looking for. Rudi has now for about 20 years made the 4345 piston CC, a .750" bore valveset 4/4 instrument with an 18" bell diameter. He has also made a very few model 4345 rotor CC models, which I may like even better than the piston version. Rudi considers a .750" bore to be his 3/4 instrument valveset, so the 4345 rotor instrument has the same valveset as the 3/4 rotor CC on something close to a 5/4 York-sized body. So, this opens up the instrument even more in the volume department, particularly in the low range, without sacrificing anything in the high range. So, if you can imagine playing a York 5/4 CC with a 5-rotor valveset and 2nd slide trigger, this is it. And, they are readily available for less than $20,000.00.
The bore size of each Rudolf Meinl 4345 piston tuba I've had the pleasure to play (3 or 4 including the one I currently own) has been .709" (18mm). I have measured.
Every 3/4 Rudolf Meinl CC tuba that I've seen had a bore size around .728" (18.5 mm).