anotherjtm2 wrote: ↑Thu Jun 10, 2021 10:34 pm
iiipopes wrote: ↑Tue Jun 08, 2021 4:55 pm
That was my experience also when I removed the recording bell stack off my 186, replaced the entire stack with a Besson bell, and also had to lengthen the tuning slide. Link:
viewtopic.php?f=35&t=61956&p=515531 . Hmmm. Now if only Miraphone would take notice to correct their notorious flat fifth partials as we did!!!
Congrats on selling your horn.
Thanks. I'll probably regret it eventually.
There must be some tradeoff, right? Like shortening the bell and lengthening somewhere else improves the D and Db but flattens the high end a little? I don't know. My German rotary C of a similar age usually wants me to play E as 1-2; Eb is more lippable, but 2-3 is sometimes worth the trouble.
I'd like to try a 188 sometime to see if it does better.
The more cylindrical tubing, the more spaced out the overtones tend to be; this tends to sharpen the upper register and flatten the lower register. Conversely, the more conical tubing, the more compressed the overtones tend to be; this tends to flatten the upper register and sharpen the lower register (ask a flugelhorn player). On my 186, I had my tech put on a Besson 17-inch New Standard BBb bell. At the critical area in the taper of the bell around the leadpipe up to the flare, the Besson bell is slightly lesser diameter. This also keeps the overtones up. The folks over at the trumpet forums have long-winded discussions about the various Bach bells and their taper and effect on intonation; Schilke had at least three different tapers.
The particular tone desired does have a lot to do with the bell. If you like the tone of your German C, the I would leave it as-is. I prefer the tone of the Besson bell, especially for concert band work, over the tone of either the older Miraphone "stovepipe" 16 1/2 inch "point-and-shoot" bell or the newer Miraphone 17 3/4 inch "vanilla" toned bell. I have heard that some of the Yamaha bells are derivatives of the Besson and also work well, especially as economical repairs.
But you are right: when you go changing bells and/or other major hardware, you never know where the intonation characteristics will end up. I got extremely lucky, and have a tuba that not only intonates well, but has a big tone with good core and efficiency that I can use to support everything from a quintet to a 60-piece concert band single handedly.
Cheers!
