Bach did not write dynamics (f/p) because Baroque music uses "terraced dynamics" (loud on the downbeat, soft on the upbeat). In your duet, practice having Euphonium 1 play forte when they have the subject, while Euphonium 2 plays mezzo-piano as the accompaniment.
No transposition needed.
The most common application for euphonium is the . These arrangements, such as the Tubarama edition , split the original keyboard parts between two tenor-clef instruments. two part invention euphonium pdf
Working through two independent voices—often performed as duets—sharpens a player’s ability to hear and balance multiple lines simultaneously. Performance as Duets Bach did not write dynamics (f/p) because Baroque