Here’s one from Carroll County and from the unique repertoire of Sidna (banjo) and Fulton Meyers (fiddle).
In this banjo-fiddle duet the fiddle is tune like standard GDAE but lower and played in G fingering. It could be F or E if low enough. Who cares as long as it sounds good, huh? I think it’s kinda cool down low like that. No rules have to apply.
It didn’t matter to so many old-timers whether they were tuned to a standard pitch. Low bass and high bass were two ways to tune a fiddle to some, and lower pitch overall was good because it didn’t risk string breakage. Think how hard it would be to replace a broken string in a rural area miles from any town. It just had to sound right with itself and with another instrument if the player was in a duet setting with a banjo player.
Sidna uses a typical modal tuning on the banjo to play this tune. It was used by other old-timers from this region and beyond for certain tunes. To play in actual G then gEAC#E (A modal almost) works if you sort of chord it like a guitar G chord shape. In using this tuning to play along with certain fiddle tunes, the player notes out the melody as the tune progresses always coming back to the root chord form of the fingers. Brushes are on the closed chord part or open to give the lonesome drone sound. A very regional, older sound that is almost lost in these times (in my opinion).
Hard to explain.
Later in the evolution of string band music, guitars came along to be common and likely forced many banjo and fiddlers to tune their strings UP to standard pitch to be ‘in tune’ to make music. “Proper” pitch wasn’t actually necessary for the solo player and neither was it necessary for this authentic mountain duet. The rules of tuning to “proper” pitch aren’t as strict as the rule of being in tune and simply keeping time together.