Hello, I am playing around with the “Brass Band” template which includes a lot of transposing instruments. I have my own 224EDO that I have mapped using Sagittal accidentals. First, my observations:
Here, you see the result of a custom “F major” key signature. The bass trombone has the original as per my definition. What’s really cool: the E-flat instruments are automatically creating their own key signatures, meaning this “D major-ish” key signature is not anything I have pre-defined. What’s not cool: the B-flat instruments are not transposing at all. I have no idea why not. For more context, see this part of the accidental list:
If you count from the natural sign (meaning exactly what you think it does) the accidentals selected by the E-flat instruments are being selected exactly one 224EDO step off of that natural, which is interesting. I know that Dorico automatically selects the “closest” # of steps compared to the instrument definition here:
So - with all that context, I am wondering if it is possible in a future update of Dorico to add in this “Transposition” section of the instrument definition something like a checkbox of “Uses custom EDO”, which adds a dialogue to select the EDO and the specific steps in that EDO (replacing the default dialogue here that uses note names). I do not think that such a change, if implemented with care, would impact existing scores that still only want to use your default built-in transposing algorithms. In my example here, that would allow me to dial in the # of steps that I really want the E-flat and B-flat instruments to transpose to.
Also: I do not particularly care if the left-to-right order of how the accidentals get automatically generated match up with what I would do, as long as they’re there. I can always change my original custom key signature definition to match.