Here are 96 measures of half-note guide tones around my rs7 (OneLife) progression. They won’t sound like much if played exactly as written, but if you use your imagination, you can fill in on the quarter and eighth-note levels. I seem to be gravitating toward a lazy hornpipe feel, but it also works as a jig if you pretend the half notes are really dotted quarters
The wikipedia has a great entry on diatonic vs. chromatic:
As the article says, these two terms are most often used in pairs, because they mean very different things.
The section on “modern meanings of diatonic scales” is particularly interesting to me, because it confirmed my suspicion that there is no generally agreed convention with regard to whether the melodic and harmonic minor scales should be considered diatonic. They are not in my book, because you can’t play them on a folk harp.
I actually like what the Harvard Dictionary of Music says: basically that diatonic refers to the white keys of the piano. This is where I learned the mode system, and I think most students get it this way too. It’s really fun to hear each of the diatonic “Church Modes” over a Root-5th-8th drone in the left hand.
On the mountain dulcimer, we have to remember that the 6+ fret, which is added to most modern dulcimers, changes the game a little bit, as does playing across the fingerboard as opposed to just going up and down the melody string.