F major is the purest campanella lesson on the instrument. After the first note — F on the E string — the entire scale alternates between just two strings: G, then A, then G, then A, all the way to the top F. No two consecutive notes ever share a string, which means every single step overlaps the next. Played slowly with everything ringing, it stops sounding like a scale at all; it sounds like a music box being wound.
Reading the map
The open G and open A anchor the low half; the upper half climbs the same two strings in parallel — Bb at the G string’s third fret against C at the A string’s third, then D and E at the seventh, then the top F at the tenth. The hand makes two small, clean shifts (to the seventh fret, then the tenth) and the fingering pattern barely changes shape as it goes. That climb is the trade this key makes: where campanella C major stays low and leans on open strings, F major buys perfect alternation at the price of a little altitude.
Practicing it
Treat the two shifts as the drill: play the five notes below the first shift in a loop until the move to the seventh fret lands without looking, then add the top three. Keep both strings ringing through each shift — the open A can sustain right across it if your hand travels lightly. Then test yourself against the conventional F major position maps: same pitches, opposite philosophy. When the alternation feels natural, Amazing Grace uses this register and this ringing logic on a real melody.