3900 / 18210 · Workshop 21 — “Stella by Starlight”: Ambiguous Tonal Center, Non-Diatonic Harmony, and Hearing Function Without a Comfortable Home Key← prev⊞ allnext →
21.18Half-diminished chord as a signpost
A m7♭5 chord often announces:
minor cadence coming.
Examples:
Bm7♭5 → E7 → Am
Em7♭5 → A7 → Dm
Am7♭5 → D7 → Gm.
This is high-value pattern recognition.