The Key of D — Dobro

D major harmonises to D – Em – F#m – G – A – Bm – C#°; D minor to Dm – E° – F – Gm – Am – A# – C. Most of the country repertoire in this key lives on three of those chords — the tonic, the subdominant and the dominant — plus the relative minor when a song wants one darker turn.

The dobro chair carries slide fills and turnaround answers, the same job the pedal steel does on records that carry one instead. Face-up in open tuning, a chord here is a bar laid straight across the neck, or tilted a fret or two, rather than a hand shape — every diagram below is such a bar position, and a quality open G cannot spell that way is marked instead of drawn.

Learn the tonic-subdominant-dominant grammar in D until your hand goes there without asking, then add the relative minor, and most of the repertoire in this key is already playable.