I kept messing around with my Symphony, Orchestra Grand, and Imperial cup mouthpieces with my 32-inch tall Holton (identical bell and bows to vintage 4/4 York) BB-flat tuba.
This instrument is a little bit smaller than a King 2341 the Eastman knockoff, and the Eastman C versions, but it's really quite similar.
I came up with a roughly "Helleberg-deep" yet BOWL cup mouthpiece prototype (and heck no, it's NOT a "Bach 7" and it's also NOT a "PT-88") that works better than ANY of those mouthpieces listed above ON THAT PARTICULAR INSTRUMENT and FOR ME.
I'll probably do a "run" of these as well for selling.
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The only other bowl cups in the "Sellmansberger" stuff are shallow bowls:
- Solo (stainless steel modular)
- Shallowberger (one-piece silver plated brass...EXTRA shallow, with a very small throat opening).
So this new bowl cup mouthpiece will be a REGULAR DEEP (not extra deep) cup mouthpiece and with - pretty much - a regular - throat that opens up to a large exit bore.
again: I LIKE it with my 19-inch bell .687" bore contrabass tuba.
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I'm not "getting into" this until 2025, but - if there's interest, lemme know (not collecting money now, only soliciting interest).
It rocks-and-rolls with THIS tuba, in particular: PHAT POWERRRRR !!!
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BIG sound, BROAD sound, a good bit of "fist" in the sound (when the player "gets on it"...and - again) with a medium large bore tuba.
I DON'T dislike how it sounds with my huge tuba...but - with that tuba - it's not my favorite mouthpiece...at least, not right now.