Borrow the minor 4, then re-hear it as the ii of the key a minor 3rd up — suddenly a ii–V to b3 assembles itself out of parts you already owned. The textbook mixture modulation: one loan from the parallel minor buys a whole new address.
hear it in the textbook mixture modulation · art-song pivots
Lead-in — how players set it upSet up the borrow honestly: 4 major first, then the mist.Or reach 4- through 4Δ7 — daylight, mist, doorway.Or from 2ø⁷ — the borrowed cousin points the same way.Follow — where it usually goesFurnish b3's house — its 6- and 4 make it home.b3's world borrows back: its 4- points another minor 3rd up.Or return by mirror — new 6⁷ is old 5⁷'s twin, ride it home.
The borrowed 4-'s b6 is your bridge note — it's diatonic in the new b3 key; sing it across and you're already home.Target tones (in C)Fm7 — lean on Ab (b3) · Eb (b7)Bb7 — lean on D (3) · Ab (b7)Eb — lean on G (3)Half-step wiresEb ↘ D · D → Eb · Ab ↘ GAcross the borderhold these into Eb: G