Upright Bass: C# Gypsy Minor Over the Changes
Where C# Gypsy Minor lies at this seat, and what a chorus takes out of it.
C# Gypsy Minor runs 7 notes to the octave, laid out here on EADG with every C# flagged. Mid-chorus the pattern is not what you need; where the root is when the chord changes underneath you is.
Harmonic minor with a raised 4th — two wide, yearning steps (b3 to #4, b6 to 7) give it a smoldering, theatrical intensity. Dark, exotic, and full of drama.
Heard in: Hungarian and Romani folk, Liszt's Hungarian Rhapsodies, gypsy jazz, klezmer, and neoclassical metal.
The upright takes a chorus less often than anyone, and that is exactly why these matter: the notes between one chord root and the next come out of a scale, and a walk that lands on the wrong one is the loudest wrong note in the room.
Play it slowly against the audio until it stops being a shape, then put it over two bars of a form and let the chord tones decide which of the notes you actually keep.