Tritone-Sub Walking Bass

Walking ii–♭II7–I with rootless RH chords, twelve keys

Replace the V chord in the walking-bass exercise with its tritone sub (♭II7). Now the bass walks chromatically downward: ii root → ♭II root → I root, each a half-step apart. Inside each bar the bass still does 1-3-5-octave; between bars it descends by half-step instead of cycling by fourth.

The RH chord voicing is the rootless A-form (3-5-7-9) of each chord. Because ♭II7 shares its tritone (3 and ♭7) with the original V7, but its other chord tones are all a half-step away from V's, you get a beautiful effect: three of the four upper voices descend by half-step at each chord change. The whole exercise sounds like the harmony is melting downward.

LH

Walking bass 1-3-5-8 on each chord; root descends chromatically.

RH

2-and-4 backbeat stabs, rootless A-form chord (3-5-7-9), three voices slide down a half-step each change.

C major

F major

B♭ major

E♭ major

A♭ major

D♭ major

G♭ major

B major

E major

A major

D major

G major

The Daily Drill

Hear the slide

4 minPlay one key very slowly with the metronome on quarters. The bass line walks down chromatically at every bar change — D, D♭, C. Listen for that descent as the spine of the whole phrase.
10 minCycle three keys at a time. The fingering for the RH chord is identical from ii to ♭II7 (same A-form rootless shape, just transposed down a half-step). The hand barely moves.
3 minCompare side-by-side: play the regular walking-bass exercise (V7 in bar 2), then this one (♭II7 in bar 2). Same destination, different bass line. The ear chooses.
3 minApply: take any tune with a ii-V-I and walk the bass with the tritone-sub substitution on the V chord. Almost any standard accepts this reharm without resistance.

Three voices, all sliding down a half step

The tritone-sub chord (♭II7) shares its tritone — the 3 and ♭7 — with the V7 it substitutes for (in C: G7's B/F = D♭7's F/C♭, the same two pitches). So the V7→♭II7 swap is essentially free harmonic real-estate. For the ii→♭II7 motion practised here, the relationship is different: the ♭3 of ii is the same pitch as the 3 of ♭II7 (in C: F is the ♭3 of Dm7 and the 3 of D♭7), so one voice holds. The other three voices — the 5, ♭7, and 9 — each drop a half step from ii to ♭II7. Maximum chromatic motion, minimum hand displacement.

Bass descends. Three voices slide. Same destination, melted approach.

80 bpm

Sound