transposing between keys and modes
Please note before reading - I wrote a lot of this out to remind myself what to do the next time I forget how to transpose to a mode in a given key. I solved most of my concern as I went along, but there is one residual question at the very last line. If anyone wants to take a crack at it, you could probably just scroll to the very last line. Ty.
I am having a bit of trouble understanding the way the Notes->Transpose works.
It seems like - when you select a gamut of notes, say something simple, like C-D-E-F-G in C Major starting on middle C in a wholestep - wholestep - halfstep - wholestep order, but then you use the arrow up to raise it, it will preserve the intervalic relationships. It's actually easy to see in C Major, especially when you start on the tonic, and then raise the scale to D because suddenly sharps and/or flats appear in a key that otherwise would have no sharps or flats.
To make it a bit more challenging, which is more to my concern - supposed we used a key like E Major, and we wanted to write in the Lydian mode - such that we would have to establish the fundamental as A, if I have it right. I guess I could just select everything I wanted to transpose from E Major to A Lydian, and then use the arrow key a few times until the fundamental of the Lydian mode was on A, and then I could just delete (most, if not all) the accidentals appearing on the staff.
That seems like it should work, yes? But in all cases? The arrow key can function differently depending on whether one is going up (for sharps) or down (for flats), and sometimes it will alter the intervals in the scale. Set a Major scale on C, select all notes, and then use the arrow keys to raise the notes to A, and then keep moving it up and down - and you'll see there's more than one pattern evolving.
When I look at the "Transpose" Palate, it suggests, if one can understand it to get it to work right - what might be a simpler and more accurate way, except I dont get it. It has transpose by Key, Interval and Diatonically (with or without alterations).
By Key - Starting on C, writing a C Major scale, selecting it, arrow key nudging up to A, and then hitting "Transpose to A Major" yields an A Major Scale with a bunch of accidentals against the notes in the staff lines with no change in Key signature.
By Interval - Starting with a C Major scale on middle C, selecting it, and then raising it a perfect fifth will raise it to G, keep all the intervals in relationship to one another, and you end up with a G Major scale with the accidental on the F note in the staff.
Now for the kicker... which seems to give me what I want for modal purposes, but which I dont completely understand...
Transpose Diatonically - with the option to preserve "degree alterations" - Starting with a C Major scale on middle C, selecting it, and then transposing it up a fifth moves it to G with no accidental on the F note or change to the key signature. This would put it in a mixolydian mode. It would seem you could reliably use this technique to transpose to all the other modes within a key, too. Please correct me if I am wrong.
The part I dont get is - what is the "Preserve Degree Alterations" checkbox for?
Comments
First, note that the transposition facility isn't really meant to handle specific re-configuration of a melody like changing it from major to lydian or whatever. If you can trick it into doing that, great, but it really is meant for literally transposing. Either a literal (chromatic) transposition to a new key, or a diatonic transposition to a new pitch level within the current key.
The latter - diatonic transposition - really only musical sense if the line itself is diatonic. If the melody has chromatic alterations, then there is an open question of what to do with the notes not int he key. That's what the option you asked about controls. If you say you want to transpose by a diatonic third, then scale degree 4 will transpose to scale degree 6. If the original pitch was, say, #4, then this option controls whether it gets transposed to plain 6 or to #6.
If your melody is completely diatonic, then indeed, the diatonic transposition will put it in another "mode" (not really in any proper Renaissance meaning of the term, but it will use the right notes accord to the modern colloquial use of the term), and it won't matter what value you give that option. Only if the melody contains chromatic alterations will that option be relevant. With the option set, you'll have the same chromatic alterations in the transposed melody. With the option unset, your transposed melody will be diatonic.
Note that the first thing you describe doing - transposing a melody first using the arrow keys and then for some reason transposing it again using the menu - makes no sense to me. If your goal is to transpose from C to A, just use the menu, don't mess with the arrow keys. The key signature will get transposed if it is part of the selection (and you haven't disabled the option to transpose key signatures).