something that probably no one would ever dare try

[bloke]

I have worked on Holton model 345 B-flat that all looked about the same and all featured factory parts. Some of them featured unusable third partial pitches, whereas some of them were perfect on the same pitches.
I’m going to keep my mouth shut - regarding any future guesses, and encourage the engineers pontificate, so that I can continue to giggle while trolling them.

[iiipopes]

I have worked on Holton model 345 B-flat that all looked about the same and all featured factory parts. Some of them featured unusable third partial pitches, whereas some of them were perfect on the same pitches.
I’m going to keep my mouth shut - regarding any future guesses, and encourage the engineers pontificate, so that I can continue to giggle while trolling them.

And make money fixing the horns they design!

[Rick Denney]

The computer models make simplifying assumptions because there are too many independent variables and nonlinearities. This isn’t like hi-fi loudspeakers, and those are nothing trivial to design. The interactions in the mouthpiece cup alone make for a challenging model even using only numerical methods.

The Germans were sharing software a decade or two back that was based on a model that used a standardized transducer. I don’t know what became of that. They probably still use it, but they aren’t designing as many new tubas as they were, it seems to me.

My Holton plays the third-partial F in tune, but with other compromises in the open bugle series. Those are easier to fix. It was said that the Conn 2xJ notoriously flat third partial was a compromise to get the fifth partial in tune, since that open third partial can be fixed using 1-3. That was certainly not the only tuning challenge I had on the 20J I owned briefly. I don’t find that newer instruments are particularly less challenging, even if they present different challenges. I do find that some newer instruments are so filled with compromises that every pitch is wonky, but not that wonky. Would you rather have one or two stinker pitches that require significant alternate fingering or a dozen pitches that are close enough to allow conventional fingering but still have to be lipped? I think it would depend on the consequences of that lipping on tone.

I do find that the more I practice centering pitches with the tuner providing verification, the more in tune I play, generally. That and the more I listen to the pitches around me. I suspect the ears are where the training is needed.

There’s your engineering input.

Rick “generally plays flat” Denney

[bloke]

Your post’s overall message read more as from an informed musician’s aspect, rather than that of an engineer. It’s a rare model that is completely easy to play in tune, and I tend to embrace those rare ones over the ones that someone might claim offer “that sound” (with me sometimes wondering what “that sound“ is supposed to be – when some of those Instruments are demonstrated to me by their champions ) , as I believe I can make most any well-functioning tuba’s sound marketable.
When a tuba both lines up quite well with equal temperament and is ALSO quite flexible, I’m in heaven - because thirds, fourths, fifths, and sixths (in various chord inversions) require placing pitches so as to keep the instruments above me from acoustically doing the “wah-wah-wah-wah-wah” thing.