Following the chords under a song
Number the chords of a song in C, follow the bass to find them, hear V pulling home to I, and count bars to catch every change.
In the key of C, each chord gets a Roman numeral for the scale note it is built on: C is note 1, F is note 4, G is note 5. Capitals mean major, small letters minor.
| Numeral | Chord | Notes | Bass note |
|---|---|---|---|
| I | C | C E G | C |
| IV | F | F A C | F |
| V | G (or G7) | G B D (F) | G |
| vi | Am | A C E | A |
LISTEN LOW
Follow the bass
Chords are hard to name while the singer is in the way. So listen under everything, to the lowest note. In most pop and folk songs the bass plays the root of each chord, the note the chord is named after. Hum along with the bass instead of the tune, and you are humming the chord names.
In C, a bass that goes C, F, G, C is almost always the chords C, F, G, C: I–IV–V–I. From C, the bass climbs 5 half steps to F and 7 half steps to G.
Check yourself
Parisa hums along with a song in C. The bass goes C, F, G, C, while the singer holds E, A, D, C over it. Which chords are playing?
- Em, Am, Dm, C, following the singer's notes
- C, F, G, C: I–IV–V–I
- C, G, F, C: I–V–IV–I
- Only C, because the song is in C
Show the answer
C, F, G, C: I–IV–V–I
Yes. The bass gives the roots, and C, F and G are I, IV and V in C. The singer's E, A and D are notes inside those chords, not their names.
THE PULL HOME
V wants to go to I
Of all the chords, V pulls hardest toward I. In C, V is G: G B D. Its B sits one half step under C and leans up into it. Add F on top and you get G7: G B D F. Now F leans down one half step into E as well. Most listeners hear V or V7 as a question that C answers.
Play G7 and stop. Most people feel the music is waiting. Play C after it and it settles. That feeling is your cue: the chord just before a line ends is very often V.
G7 moving to C, note by note.
G7 = G B D F C = C E G
B -> C up 1 half step
F -> E down 1 half step
G -> C bass: up 5 half steps
B up to F = 6 half steps, a tritoneTwo notes each move by the smallest step there is, into C and E.
That double half-step squeeze is a big part of why V7 to I sounds so settled.You don't need to name these notes while you listen. Just notice the moment the tension lets go. That release is very often V going to I.
Check yourself
Hamid hears a song in C pause on a G7 chord just before the chorus. Most listeners would expect the chorus to start on C.
Show the answer
True
True. G7 is V7 in C. Its B wants to rise to C and its F wants to fall to E, so the ear expects I next. Songwriters use exactly this pause to launch a chorus.
The two patterns you'll hear most
I–IV–V–I
C, F, G, C. Bass: C F G C. All three chords are major, and most people hear it as bright and sturdy. It sits under a great deal of folk, blues, early rock and children's songs, and it ends at home.
I–V–vi–IV
C, G, Am, F. Bass: C G A F. The minor vi adds what many listeners describe as a touch of longing. Songs that use it usually loop it again and again, so instead of ending, it circles back to C.
Check yourself
In C, match each bass line to its chords
Show the answer
- C F G C → I–IV–V–I
- C G A F → I–V–vi–IV
- C A F G → I–vi–IV–V
- C F C G → I–IV–I–V
WHEN IT CHANGES
Count the bars
Chords usually change on the first beat of a bar, and often stay for one or two whole bars. So tap the beat and count bars out loud, saying the bar number in place of 1: 1 2 3 4, 2 2 3 4, 3 2 3 4, 4 2 3 4. Each time the bass moves, note which bar you are in.
If the bass moves at the start of every bar you count, the chord changes every bar. If it moves only at bars 1 and 3, each chord lasts two bars.
Mahsa's chart for a four-bar loop in C.
She counts bars out loud and writes the bass at each bar start.
count: 1 2 3 4 | 2 2 3 4 | 3 2 3 4 | 4 2 3 4
bass: C | G | A | F
chord: C | G | Am | F
job: I | V | vi | IVOne chord per bar: I–V–vi–IV, then the loop starts again on C.
A low A under a song in C usually means Am, the vi.Bar counting also catches slow changes. If the bass stays on C through 1 2 3 4 and 2 2 3 4, write C for both bars.
Check yourself
Nima counts bars out loud over a song in C. The bass sits on C through bars 1 and 2, moves to F for bar 3, to G for bar 4, and is back on C at bar 5. What does he write?
- | C | F | G | C |
- | C | C | G | F | C |
- | C | C | F | G | C |
- | C | C | F | F | G |
Show the answer
| C | C | F | G | C |
Right. C lasts two bars, so it is written twice, then F and G get one bar each before home. In numbers: I, I, IV, V, I.
Check yourself
In the key of C, which chord is it?
- The bass lands on G
- The bass lands on F
- The notes G B D F
- The notes F A C
- The chord most songs in C end on
- The chord that answers G7
Show the answer
I (C): The chord most songs in C end on, The chord that answers G7
IV (F): The bass lands on F, The notes F A C
V (G or G7): The bass lands on G, The notes G B D F
Lesson recap
- Number chords by the scale note they're built on: in C, I = C, IV = F, V = G and vi = Am.
- Follow the bass: it usually plays each chord's root, so humming it names the chords.
- V (G or G7) pulls hardest to I: its B rises to C and its F falls to E.
- I–IV–V–I (C F G C) and I–V–vi–IV (C G Am F) are the two patterns you'll meet most.
- Count bars out loud, 1 2 3 4, 2 2 3 4, and note the bar where the bass moves.