Very nice! You may want to include a natural accidental, too, so that a range like B-flat to B-natural could be specified.
A line between notes of an altered unison should incline up or down depending on the interval — does the font support that case? (Example from Behind Bars)
well, you said you were open to suggestions so… how about stacked noteheads for ambiti? (ambitus)
(That could probably justify being its own font, I suppose.)
You mean like this?
That’s certainly possible. I suppose we’d just need quarter noteheads? What happens with smaller intervals (thirds and seconds)?
Would we need accidentals, too? Because that would make things complicated (21 pitches times 4 different accidentals results in “84 over 2” variations, so that’s 3486 glyphs… 
Accidentals would probably be necessary, but perhaps this might be a good use case for combining characters?
For the ambitus, I think small intervals would either have no line, or place a line to the left of the notes (ike cluster notation), but I am not sure.
For accidentals in the ambitus, and perhaps the ambitus itself, maybe use combining characters instead of ligatures?
Combining characters are probably a good idea. I’m not sure if they can handle variable horizontal positions (when the interval is smaller than a fifth, one of the accidentals needs to move sideways…). I’ll look into this, but it might be tricky. Yay, fun new project 
Yes, just like that.
As far as I know, these are only used for vocal works (@benwiggy could correct me on this) and I doubt they are ever smaller than a fourth wide.
Ambituses are already possible in Dorico quite easily: a 2-note chord, no stems. The Line needs manually positioning. And you get a barline after, which you need to deal with somehow. You could just leave it in.
But yes, they often feature accidentals, and most music is more than a fifth wide!
Well, there’s the good old fashioned zero length dashed barline trick. (Assuming you don’t need a real dashed barline elsewhere.)
Tim, you can use a zero-width character.
Edit: you can see this in action in MusFrets. It’s easy to place multiple characters “on top of one another” if they’re zero-width. Basically, the cursor just doesn’t advance.
While it’s the most common in vocal music, I’d like not to restrict the display of ambitus to vocal parts only. It can be quite useful for unspecified or multi-purpose instrumental parts as well, e.g. in consort music.
(Nerd-alert: the Latin nominative plural of ambitus is ambitūs with a long ū 
)
I was taking a guess with ambiti lol. I knew it wasn’t ambituses! And ambitæ didn’t seem right either.
Now I’ll remember:
Ambitus > ambitus
Moose > moose
Luckily, English is not Latin. We have assumed countless words from Greek and Latin and made them our own. And there’s a slight snobbery that we don’t feel compelled to use plurals from other languages. Two kebablar, anyone? For our Backpäcke?
We even make singular words from foreign plurals, like agenda, or, God help us, ‘two paninis’…
My favorite is “parking garage” which to French-English speakers hits like “parking parking”.
Surely you intended French-American speakers …?
I love the drift of this thread, I have to open more of them
