The Plagal Cadence
A plagal cadence moves from IV to I. In C major, that is F major to C major. It reaches the tonic without the leading-tone resolution that gives V-I its sharper sense of arrival.
- IV to I
- F to C in C major
- often called the Amen cadence
same family
The progression
- IV
- I
Follow the voices
F major contains F-A-C. C major contains C-E-G. In a close upper voicing:
- C can remain as a common tone
- F falls by semitone to E
- A falls by whole tone to G
The upper voices settle through small downward steps. The root-position bass moves F-C, a perfect fourth down or fifth up. Separating bass motion from upper-voice motion gives a more accurate picture than saying that every note falls.
Compare plagal and authentic motion
| Feature | IV-I | V7-I |
|---|---|---|
| In C | F-C | G7-C |
| Leading tone B | absent | present and rises to C |
| Dominant tritone | absent | B-F resolves to C-E |
| Common tone | C | G can remain |
| Typical effect | tonic confirmed more gently | stronger cadential closure |
The musical context still matters. Rhythm, melody, bass position and placement in the form can make either arrival stronger or weaker.
Is every IV-I a cadence?
A cadence is a phrase ending, not only a pair of chord symbols. IV-I can occur inside a phrase as ordinary plagal motion. It becomes cadential when melody, metre and form place it at an ending.
In some classical repertory, IV-I follows an authentic cadence and prolongs an already established tonic. In gospel, soul, rock and pop, plagal motion can carry much more structural weight.
Try three versions
- Major plagalF-C gives the diatonic IV-I sound.
- Minor plagalFm-C introduces A-flat and the line A-flat-G.
- Double plagalB-flat-F-C gives flat VII-IV-I in C.
The minor iv variation
Changing F major to F minor replaces A with A-flat. The move F-Fm-C creates the chromatic line A-A-flat-G. This is modal interchange: iv is borrowed from C minor.
The result is still plagal because the final root motion is F-C. The borrowed note changes the colour and strengthens the semitone voice leading into the tonic.
Make it yours
- Use it after V-I
Add IV-I as a short tag after a stronger authentic cadence.
- Put scale degree 1 in the melody
Hold C above both chords to make the shared tone audible.
- Move it inside a loop
Repeated IV-I motion can confirm a tonal centre without stopping the track each time.
When it is useful
Use plagal motion when you want to return to the tonic without relying on dominant tension. It is especially useful in modal, gospel-influenced and loop-based writing where V-I would change the harmonic character too strongly.