windshieldbug wrote:I will submit that the term has much more to do with intended use than with subleties in construction.
So, what was Holst's intention in
The Planets? The part is marked tenor tuba, but it's written in the treble clef just like a brass-band euphonium part.
But I see your point. Holst was actually demonstrating the notion when he wrote "tenor tuba" in the part rather than "euphonium", even though, as Bevan says, there's little doubt as to the instrument he intended. He wrote tenor tuba precisely because it was an orchestral part and not a band part.
To address some other issues: I can't think of a tenor tuba that has a bore substantially bigger than modern euphoniums, when reported with the same consideration that is routinely applied to tuba comparisons.
For example, nobody calls a Miraphone 186 a BAT, despite that its official bore is larger than a Yorkophone. Everyone expects rotary instruments to have a larger bore merely because the valves are a bit further along in the bugle. Thus, one would expect an Alex 151 to have a larger bore than, say, a Willson 2950, even though both are about the same size.
And nobody expects, say, an Alex 163 BBb to sound like a Miraphone 186, even though most non-tuba-playing observers would be hard-pressed to note the differences from photos. Nobody looking at an Alexander 163 would expect it to sound like a Besson 99-whatever Bb bass. Those instruments are no more different than an Alex 151 and a Besson Sovereign euphonium.
We generally consider the differences between top-action, front-action, piston, and rotary configurations to be differences of varietal rather than species. In the genus Tuba and species Contrabass, valve type and arrangement (not to mention bore and bell size) are routinely described using plain adjectives. Such as: The Alexander 163 is a large-bore 4/4-5/4 rotary contrabass tuba.
If we try to make top-action euphoniums a different species from rotary tenor tubas, we are giving ourselves an organological headache we don't need.
I suspect a good player, with proper choice of mouthpiece and a specific commitment to a certain tonal concept, could make any decent, large euphonium sound similar enough to an Alex 151 so that the non-tuba-playing public would not note or care about the differences. It is true that an orchestral tuba player using a 151 for Bydlo will have a different tone concept than a brass-band euphonium player using a Willson 2950, but I think the major difference is behind the mouthpiece.
Thus, in the genus Tuba, there are tenor, bass, and contrabass species in common use. Each species is respresented by huge variety, just as homo Sapiens is represented both by tuba players and viola players, surely confounding even the broadest interpretation of the word
species.
Rick "quoting Tolkein: Sheep look different only to other sheep, or to shepherds" Denney
