The grip
One fixed hand shape. Learn it once and let the bass do the naming. The keyboard lights the four notes you hold; tap any bass note underneath — buttons, keys, or a MIDI keyboard — and hear the same motionless hand become a different chord.
Tap a bass note — the hand (B–D–F–A♭) never moves; the name does.
| Notes (close voicing) | B–D–F–A♭ |
|---|---|
| Parent scale | Diminished (octatonic) scale |
| Symmetry | minor 3rd and tritone |
| Readings | 8 functional, 9 total |
One hand, 8 chords: the readings
Every row below is the same four notes with a different bass underneath. The intervals are computed from that bass, so the chord name is arithmetic, not opinion. Three stars means every defining tone is present; two stars means one key tone is implied; a cross marks an avoid-note collision that no bass rescues.
| Bass | Intervals | Chord | Rating | Use |
|---|---|---|---|---|
| D♭ | ♭9 · 3 · 5 · ♭7 | D♭7♭9 | ★★★ | Dominant. Minor 3rd symmetric with E7♭9, G7♭9, B♭7♭9. |
| E | ♭9 · 3 · 5 · ♭7 | E7♭9 | ★★★ | Dominant. |
| G | ♭9 · 3 · 5 · ♭7 | G7♭9 | ★★★ | Dominant. |
| B♭ | ♭9 · 3 · 5 · ♭7 | B♭7♭9 | ★★★ | Dominant. |
| D | R · ♭3 · ♭5 · 6 | Ddim7 | ★★★ | Diminished 7th. Enharmonic with Fdim7, A♭dim7, Bdim7. |
| F | R · ♭3 · ♭5 · 6 | Fdim7 | ★★★ | Diminished 7th. |
| A♭ | R · ♭3 · ♭5 · 6 | A♭dim7 | ★★★ | Diminished 7th. |
| B | R · ♭3 · ♭5 · 6 | Bdim7 | ★★★ | Diminished 7th. |
| C · E♭ · G♭ · A | 9 · 11 · ♭13 · maj7 | None | ✗ | No 3rd, passing color only. |
Why the bass names the chord
The four notes are rootless: the root is never inside the shape. When a bass note lands beneath the grip, the intervals from that bass to each held note spell out a chord quality. Move the bass and the same physical hand becomes a new chord. Because this grip is symmetric under the minor 3rd and tritone, one shape serves an entire cycle of basses, which is why it carries so many names.
Frequently asked
What is the diminished grip?
The diminished grip is the four-note rootless voicing B–D–F–A♭, a subset of the Diminished (octatonic) scale. Eight names: four dom7♭9 + four dim7. The root is never inside the shape: the bass note supplies it and thereby names the chord.
What chords does the diminished grip spell?
8 functional readings come from the one shape: D♭7♭9 (over D♭), E7♭9 (over E), G7♭9 (over G), B♭7♭9 (over B♭), Ddim7 (over D), Fdim7 (over F), A♭dim7 (over A♭), Bdim7 (over B). Each is produced by placing a different bass note under the same fixed hand.
Why does one hand shape have several names?
A chord name is a relationship between the notes and a bass. The grip is symmetric under the minor 3rd and tritone, so a single shape reuses across an entire cycle of basses, which is why it carries so many names at no extra memory cost.
What is the strongest reading of the diminished grip?
With D♭ in the bass the grip is D♭7♭9: intervals ♭9 · 3 · 5 · ♭7. Dominant. Minor 3rd symmetric with E7♭9, G7♭9, B♭7♭9.