CLEFS:
I learned to read B-flat treble clef (as well a C treble clef)...
I would strongly recommend learning bass clef.
Less and less baritone/euphonium music is available in treble clef.
I'm reading
B-flat treble clef (euphonium, even though I'm - overwhelmingly - a tuba player) this week (good-paying gig).
I'm reading
bass clef (euphonium, even though I'm - overwhelmingly - a tuba player) next week (good-paying gig).
What does it hurt to be able to do more things?
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THE 3+1 COMPENSATING SYSTEM
EVERYTHING that you do with three valves will STILL DO EXACTLY THE SAME STUFF, if you ignore the 4th valve (over there on the side).
IF YOU CHOOSE TO DO SO, you can play your 1-3 pitches with 4, and your 1-2-3 pitches with 2-4, and you will enjoy better tuning with those two otherwise 1-3 and two otherwise 1-2-3 pitches.
Further - when you get down to "LOW G" - actually sounds as an F, as you know - (with the 4th button remaining depressed), you can execute your regular chromatic downward pattern...
2
1
12
23
13
123
and play ALL THE WAY DOWN (every white and black note on the piano keyboard) to the REALLY LOW C (actually sounds as B-flat)
This is accomplished with some tricky "compensating" plumbing.
You need not understand the tricky plumbing for it to work.
All you need to understand is which buttons to mash.
Yes...I'll sell you a new 274 (cheap) but I don't particularly like selling them on approval...I prefer that someone will have already played one.
I have (reluctantly) sold them on approval...and only one college kid returned the one sent to them (no explanation)...(I can't expect everyone to like everything that I personally happen to offer for sale, and who knows whether they even actually bought any euphonium...)
JP also offers a basic 3-valve, if that's all you need. They aren't just cheap from me, but CHEAP.