A Persian — Charango
Here is A Persian across the neck, home lit at every occurrence, ready to strum and hear.
A Persian is 7 notes to the octave (world family), drawn here across the Charango's GCEAE courses with every A marked, so home stays visible from anywhere in the pattern.
Intensely exotic — two half-step clusters (b2 against the root, b5 against the 4) and a raised 7th make it the most dramatic of the world scales. Mysterious, ornate, and tense.
Heard in: Persian and Middle-Eastern-flavored melodies, film scoring for desert and ancient settings, and exotic metal and progressive-rock riffs.
Five courses tuned GCEAE spread a scale wide for a strumming instrument: two courses share the same pitch class an octave apart, so a run can cross the twin E and land on the same note it just left. These maps mark every root so a line never loses home mid-course.
Practise it as a shape the whole hand crosses, not a ladder one finger climbs: pick four of its notes, rake them as a two-bar phrase against a slow pulse, then slide the same phrase to the next position. That is how this instrument actually uses a scale — raw material for a strummed line.