Degree alterations -transpositions.

• Aug 23, 2018 - 20:01

I want to understand how the decision is made behind this switch as I get unintended results.

1) Do you mean by "Keep Degree Alterations" in Diatonic transpositions that all non-diatonic notes will be made diatonic during the transposition ?
2a) If so, how do you decide how the altered note will be incorporated diatonically. E.g. if the non diatonic note is say a flatV, how do you decide to make it a V or a IV ? ) Just based on equal spacing principle ?
2b) If not then what do you do during "Keep Degree Alterations"

I just want to see what this switch actually does so I can understand unexpected alterations I get sometimes.

With "Keep degree alterations" off, then yes, all non-diatonic notes are made diatonic. With it on, they are preserved. No guarantees the result will be musically meaningful, but I guess it makes sense for some use cases.

As for how to incorporate the note, we honor the interval, then throw away the accidental. So if you transpose by a third, then it will go up three letter names (well, like from C to E) so it is some kind of third. Might end up being a diminished or augmented third.

FWIW, I virtually never use the "transpose diatonically" command because it really is just a slower / more cumbersome way of doing the same as Alt+Shift+Up/Down, although it's less predicatable with respect to accidentals. Since my reasons for doing the transposition might be different from one case to the next, I don't sweat the slight unpredictability of it - no mater how it deals with chromaticism, I expect I'd need to edit things later sometimes.

In reply to by Marc Sabatella

Thank you Marc.
I think I understand what you say.
So if you have two notes which are enharmonically equivalent say A#/Bflat, then by the throw away the accidental principle, "the NOT "Keep degree alterations"" will then mean two different outcomes for the 2 notes in the equivalence mentioned above ?

Ok, that means it will be brutal on those people playing loose and fast with enharmonic equivalence (as it should be). I have no problem with that.

Correct - try it out and see. For example, Eb - D# in the key of C, transpose up a step diatonically with that option off, you get F - E.

Really, there is no obvious "correct" musical meaning for this, so what happens, happens.

In reply to by Marc Sabatella

I don't like to say it, but "Keep degree alterations" allows something that is called diatonic transposition yet is actually not diatonic transposition. Diatonic transposition is undefined for out-of-scale notes.

I notice that the feature is not described in the MS3 handbook.

I tried to write a description, but this is about the best I could do:

[Place under "Diatonic Transposition"]
"Keep degree alterations"
When an accidental applies to a note and overrides the key signature, diatonic transposition of that note is conceptually undefined. When "Keep degree alterations" is off, MuseScore honors the interval literally, moving the note up or down the expected number of lines and spaces, then discards any accidental applied to the note. Otherwise any accidental is preserved.