Module 7: Improvisation ILesson 2intermediate⏱ 60 min + one week of daily work

Guide-tone lines

Reduce every chord to its 3rd and 7th, connect them through the ii–V–I, a turnaround and the F jazz blues, then write and embellish your own guide-tone line.

Why two notes are enough

Play a Dm7 shell voicing from Module 4 and take away the root. What is left, the 3rd and the 7th, still sounds like Dm7. Take away the 5th from any seventh chord and nobody notices. The 3rd tells the ear whether the chord is major or minor; the 7th tells it whether the chord is a stable major 7, a restless dominant 7 or a minor 7. Those two notes are the guide tones, and a melody that moves from the guide tones of one chord to the guide tones of the next will outline the harmony even with no accompaniment at all.

This is the simplest possible solo and also the skeleton of every sophisticated one. Bebop lines, however fast, land on these notes at the moments that matter. In this lesson you will play guide-tone lines through the progressions you met in Module 3 and Module 6, write your own, and then add rhythm and extra chord tones to turn the line into music. The arpeggio shapes from the previous lesson tell you where every 3rd and 7th sits.

The guide tones of the ii–V–I

Here are the chords of the ii–V–I in C with their spellings. Look only at the second and fourth notes of each.

Two things happen as the chords change, and they are the heart of the whole lesson:

• The 7th of Dm7 (C) falls a half step to the 3rd of G7 (B), while the 3rd of Dm7 (F) stays put and becomes the 7th of G7.
• The 7th of G7 (F) falls a half step to the 3rd of Cmaj7 (E), while the 3rd of G7 (B) stays and becomes the 7th of Cmaj7.

So through a ii–V–I the guide tones form two voices: one holds, the other falls a half step; then they swap roles. That is why a ii–V–I sounds like it is being pulled forward. Play it as two-note chords first, on strings 4 and 3, and hear the pull.

\tempo 80
.
\ts 4 4
(3.4 5.3).1{ch "Dm7"} | (3.4 4.3).1{ch "G7"} | (2.4 4.3).1{ch "Cmaj7"} | (2.4 4.3).1 |

The top voice goes C, B, B; the bottom voice goes F, F, E. Neither voice ever moves more than a half step. Any time you are lost in a progression, this is the thing to find: which guide tone holds, which one falls.

The guide-tone line as a melody

Now play the same notes one at a time: the 3rd and then the 7th of each chord, in half notes, so the line zigzags between the two voices. Below it is written in C, F and Bb, which are the keys you will use for the blues and for Autumn Leaves later in this module. In each key keep the hand in one position between frets 1 and 5.

\tempo 90
.
\ts 4 4
:2 3.4{ch "Dm7"} 5.3 | 4.3{ch "G7"} 3.4 | 2.4{ch "Cmaj7"} 4.3 | 2.4.1 |
:2 3.3{ch "Gm7"} 3.4 | 2.4{ch "C7"} 3.3 | 2.3{ch "Fmaj7"} 2.4 | 2.3.1 |
:2 1.4{ch "Cm7"} 3.3 | 2.3{ch "F7"} 1.4 | 3.2{ch "Bbmaj7"} 2.3 | 3.2.1 |

How to practise this: play the line in one key three times, then sing it while fingering it silently, then play it again. Guide-tone lines are an ear skill as much as a hand skill. If you can hear the 7th falling to the 3rd before you play it, you will find it on any chord, in any key, including ones you have never drilled.

The turnaround: I–vi–ii–V

A turnaround packs four chords into two bars, so the guide tones change every two beats. In C the chords are Cmaj7, Am7, Dm7 and G7. With quarter notes you have exactly one beat per guide tone.

\tempo 100
.
\ts 4 4
:4 2.4{ch "Cmaj7"} 4.3 5.3{ch "Am7"} 5.4 | 3.4{ch "Dm7"} 5.3 4.3{ch "G7"} 3.4 | 2.4.1{ch "Cmaj7"} |

The move from Cmaj7 to Am7 is the one place where a guide tone goes up: the 7th of Cmaj7 (B) rises a half step to the 3rd of Am7 (C). Everything after that is the familiar falling pattern: the 7th of Am7 (G) falls to the 3rd of Dm7 (F), the 7th of Dm7 (C) falls to the 3rd of G7 (B), and the 7th of G7 (F) falls to the 3rd of Cmaj7 (E). Learn the turnaround line in C, then in F and Bb from the table.

The F jazz blues

The jazz blues is the best possible workout for guide tones because its twelve bars contain every kind of chord change you will meet: a I7 that becomes a IV7, a passing diminished chord, a iii–VI, a ii–V and a turnaround. Here is the form by numerals in F and Bb.

The line below stays between frets 0 and 5 on strings 4, 3 and 2 for all twelve bars. Follow the voice leading with your eyes as well as your ears: almost every move is a half step or a whole step, and the few leaps happen where the harmony itself leaps (into the iii–VI in bar 8).

\tempo 100
.
\ts 4 4
:2 1.4{ch "F7"} 2.3 | 1.3{ch "Bb7"} 3.2 | 4.2{ch "F7"} 2.3 | 3.3{ch "Cm7"} 2.3{ch "F7"} |
1.3{ch "Bb7"} 3.2 | 3.2{ch "Bdim7"} 1.3 | 2.3{ch "F7"} 1.4 | 0.3{ch "Am7"} 4.4{ch "D7"} |
3.4{ch "Gm7"} 3.3 | 3.3{ch "C7"} 2.4 | 1.4{ch "F7"} 4.4{ch "D7"} | 3.4{ch "Gm7"} 2.4{ch "C7"} |

Points to notice as you play:

• Bars 1–3. The 7th of F7 (Eb) falls to the 3rd of Bb7 (D); the 7th of Bb7 (Ab) rises back to the 3rd of F7 (A). The I7–IV7–I7 of a blues is a pair of half-step moves.
• Bar 4. The quick Cm7–F7 is a ii–V into the IV chord in bar 5. Its guide tones move Bb to A, and then the 7th of F7 (Eb) is waiting in bar 5 to drop to the 3rd of Bb7 again, but we have already used it, so the line takes the other guide tone, Ab, instead. Both are correct; choose the one that keeps the line smooth.
• Bars 5–6. Bb7 and Bdim7 share both guide tones (D and Ab). The line simply swaps their order. This is why the #IV diminished chord sounds like a darkening of the IV rather than a new chord.
• Bar 8. Am7 and D7 are the iii and VI, a ii–V aimed at Gm7. The 7th of Am7 (G) falls a half step to the 3rd of D7 (F#), which falls a half step to the 3rd of Gm7 in bar 9? Not quite: F# falls to F, the 7th of Gm7, while the 3rd of Gm7 (Bb) arrives on beat 3. Either guide tone of Gm7 can come first; the half-step arrival is what counts.
• Bars 11–12. The turnaround in two beats per chord: Eb to F#, F to E, and then E falls to Eb to start the chorus again.

Writing your own guide-tone line

Choose any progression you know: a ii–V–I, the turnaround, the blues, or the first eight bars of a standard from the repertoire list. Then:

1. Write the chords in a row with two beats or a bar each, as the tune has them.
2. Under each chord write its 3rd and its 7th. Use the chord tables in this lesson or the chord dictionary until you can do it from memory.
3. Pick one of the two notes for the first chord. For each following chord choose whichever of its guide tones is closest to the note you just wrote (a common tone, a half step or a whole step). When both are equally close, prefer the half-step move.
4. Play the result as half notes. If a move is bigger than a whole step, look for a different choice at that chord, or accept it if the harmony itself jumps.
5. Write the other line by starting from the guide tone you did not pick, and play that one too. Over a ii–V–I the two lines are the two voices in the dyad example.

Keep the lines you write; the chord-tone solos in the next lesson are built on exactly these notes.

Embellishing the line

A guide-tone line is a map, not a solo. Three embellishments turn it into music while keeping every note a chord tone, so that check=chordtones would still pass:

• Rhythm. Play a guide tone early (on the "and" of 4 of the previous bar) or late (beat 2), hold some and clip others. The half note is only the default.
• Neighbouring chord tones. Between two guide tones insert the root or 5th from the arpeggio shape you are in. The 3rd and 7th still fall on the strong beats; the other chord tones fill the gaps.
• Octave displacement. Play a guide tone an octave higher or lower than the line expects. The voice leading is still heard, and the line gains range.

Here is the ii–V–I in F embellished with all three. The 3rd of every chord still arrives on beat 1.

\tempo 110
.
\ts 4 4
:4 3.3{ch "Gm7"} :8 3.2 3.3 :4 3.4 5.4 | 2.4{ch "C7"} :8 5.4 3.3 :4 5.3 3.3 | :2 2.3{ch "Fmaj7"} :8 5.3 2.3 :4 2.4 | 3.4.1 |

And the first four bars of the blues line, embellished the same way. Compare them bar by bar with the half-note version above: the guide tones are in the same places; they simply have company.

\tempo 110
.
\ts 4 4
:4 1.4{ch "F7"} :8 2.3 5.3 :4 4.2 r.4 | 3.2{ch "Bb7"} :8 1.3 3.4 :4 3.2 1.3 | 2.3{ch "F7"} :8 5.3 4.2 :4 2.3 1.4 | 3.3{ch "Cm7"} 4.2 2.3{ch "F7"} 1.4 |

Quiz