In What Key is The CC-A-D Tuning?
Jimmy -- you're sorta writing that tuning 'backwards'. Most people today write a tuning starting with the Bass string, not the melody strings. That helps you know what key the tuning is in. Also, most folks today do not write the doubled melody strings as 2 letters unless the string are tuned to different notes. What you have is Aeolian Mode, DAC; the key of Dminor.
DAC is in the key of D minor. Your "home" or "tonic" is the first fret on the melody string, which is a D.
Jimmy, let me add that if you are playing in a drone style, the drones themselves tell you what the key is. Drones can only be the 1st and 5th notes of the scale, so DAA is D ionian. DAd is D mixolydian. DAC is D aeolian. And DAG is D Dorian.
Dusty T., Northern California
As a musician, you have to keep one foot back in the past and one foot forward into the future.
-- Dizzy Gillespie
updated by @dusty-turtle: 02/10/19 07:15:09PM