Pedal points and modulation – free course

Two techniques will give your pieces depth and a sense of journey. A pedal point holds a note in the bass while harmonies move above it: an anchor, a sustained tension. Modulation changes key: a shift, a new landscape. Both appear in every great composer, from Bach (the pedals that open or close his preludes) to modern songs.

1. The tonic pedal: calm and anchoring

You hold (or repeat) the tonic in the bass while the chords change above. The F or G7 chords then sound "above" a motionless C: a feeling of serenity, of a familiar place. Ideal at the start of a piece, or at the very end, like a farewell.

M:4/4
L:1/4
Q:1/4=60
K:C
%%staves {RH LH}
V:RH clef=treble
V:LH clef=bass
[V:RH] "C"[EGc]4 | "F/C"[FAc]4 | "G7/C"[DFB]4 | "C"[EGc]4 |]
[V:LH] C,4- | C,4- | C,4- | C,4 |]

Bar 3: G7 over C produces a tasty dissonance, resolved in bar 4. Listen to the pedal: it "glues" the passage together.

2. The dominant pedal: anticipation

Holding the dominant (G) in the bass, by contrast, creates growing tension: as long as G doesn't fall to C, the listener waits. Classical composers use it just before the return of the theme or before the end. The longer the pedal, the more liberating the resolution.

M:4/4
L:1/4
Q:1/4=72
K:C
%%staves {RH LH}
V:RH clef=treble
V:LH clef=bass
[V:RH] "C/G"[EGc]4 | "Dm/G"[FAd]4 | "C/G"[EGc]4 | "G7"[DFB]4 | "C"[EGc]4 |]
[V:LH] G,,4- | G,,4- | G,,4- | G,,4 | C,4 |]

Tip: a pedal doesn't have to be held. You can repeat it in eighth notes, in octaves (G1–G2) or build it into an accompaniment pattern. It can even sit on top (an "inner" or "upper" pedal): a note ringing above all the chords, like a bell.

3. Modulating: changing key

The two most natural modulations from a major key:

to the dominant (C major → G major): energy, momentum, "leaving home";
to the relative minor (C major → A minor): intimacy, shadow, confession.

The secret of a smooth modulation is the pivot chord: a chord common to both keys. A minor is vi in C major and ii in G major. You arrive on it in C and leave it in G. Then all you need is the new dominant (D7, with its F♯) and a perfect cadence to establish the new key.

M:4/4
L:1/4
Q:1/4=84
K:C
%%staves {RH LH}
V:RH clef=treble
V:LH clef=bass
[V:RH] "C"G2 E2 | "F"F2 A2 | "Am"E2 C2 | "D7"D2 ^F2 | "G"G2 B2 | "Em"B2 G2 | "D7"A2 ^F2 | "G"G4 |]
[V:LH] [C,E,G,]4 | [F,A,C]4 | [A,,C,E,]4 | [D,^F,A,C]4 | [G,B,D]4 | [E,G,B,]4 | [D,^F,C]4 | [G,,D,G,]4 |]

Bars 1–2: C major firmly established. Bar 3: A minor, the pivot chord. Bar 4: D7 brings in F♯, the new leading tone — the signal that something is changing. Bars 5–8: G major, confirmed by the perfect cadence D7 → G.

4. To the relative minor

Same principle: D minor is ii in C major and iv in A minor. You pass through it, then through E7 (with G♯, the leading tone of A minor), and conclude on A minor.

M:4/4
L:1/4
Q:1/4=76
K:C
%%staves {RH LH}
V:RH clef=treble
V:LH clef=bass
[V:RH] "C"E2 G2 | "Dm"F2 A2 | "E7"^G2 B2 | "Am"A4 |]
[V:LH] [C,E,G,]4 | [D,F,A,]4 | [E,^G,B,D]4 | [A,,C,E,]4 |]

On the circle of fifths, neighbouring keys (one accidental apart) are the easiest to reach: from C, they are G, F, A minor, E minor and D minor.

Common mistakes: modulating without a pivot chord or new dominant (the change sounds accidental); forgetting to put the new key's accidental (F♯ in G) in the melody too; modulating and never coming back — in a short piece you go to the dominant in the middle and return to the tonic for the end; holding a pedal so long it becomes monotonous.

Your workshop

In the piano roll, write 4 bars in C major over a tonic pedal (a held low C), with C – F – G7 – C above.
Write 8 new bars: 2 in C, 1 on the pivot chord A minor, 1 on D7, then 4 in G major ending D7 → G.
Add a return: 2 bars over a dominant pedal in C (low G), then G7 → C.
Copy the whole thing into the ABC editor and check the accidentals (F♯ during the G section, F natural on the way back).
Variation: redo the exercise modulating to A minor via D minor and E7.
Self-check: do you clearly feel the "new ground" under your feet in bar 5, and the relief of coming back to C?