Thanks Brian G and Skip. Thinking of D A d as a tuning which allows for Mixolydian or Ionian tunes to be played is helpful. Anne Lough in her book: "Welcome to the Mt. Dulcimer" suggests that this tuning could also be called 1-5-8 or Do-So-Do. This frees up my thinking also so that DAd could also be CGc etc. Again thanks.

Think of it as having 2 fret boards, one with a C#, one without [ D mixolydian and G-ionian]. As someone once said, adding frets is like overlaying fretboards. The plus frets basically add flexibility without retuning.The melody string[s] provide the modal character and the remaining 2 provide the dronenotes which define or provide the background for a mode. Consider tunings DAC and DAd, both use the same drones to provide the background for different melody string modes. If you play a tune that doesn't use any form of C inDAd tuning, I suppose you could call it what you want [probably wrong].

Hi John. I'm not sure I understand your question, so this may not be a very helpful reply. :)

DAd is a tuning, not a mode. To distinguish between the two possibilities you mention, I'd say something like "I'm tuned DAd and the tune is in D-mixolydian" or "I'm tuned DAd and the tune is in D-major (ionian).

I know that technically a pure D A d is the Mixolydian Mode with a flatted seventh in the scale. (Example: Old Joe Clark) I also know that when a person says they play in D A d but are using the sixth and one half fret (6+) that they are actually playing an extended Ionian scale without the flat. (Example: South Wind). How then should a person who says they are playing in D A d distinguish between the two?

updated by @john-w-mckinstry: 06/11/15 07:41:46AM