# Making a plagal cadence sound convincing as an ending, How?



## caters

I am nearing the end of composing the first movement of my suite. And I plan to end the movement using a plagal cadence. But I know that a plagal cadence can be hard to make sound convincing. I mean after all, it is a subdominant to tonic motion. And most of the time if anything, the subdominant moves to the dominant for your classic IV V I or a slightly embellished version of the same cadence such as IV V vii°7 I

I know that part of making a plagal cadence sound convincing is to slow it down. V I could easily be convincing at quarter note speed. Not so easy for IV I to be convincing at that speed. But as you slow it down, IV I becomes more convincing as an ending cadence. Another thing that makes the plagal cadence more convincing is having the upper voice move between scale degrees 5 and 6, implying a second inversion subdominant chord.

Second inversion is the least stable form for any major or minor triad. And scale degrees 6 and 4 naturally want to move downwards. This leads to a convincing tonic resolution from the subdominant. Repeating the chords in a pattern like this:



> I IV IV I


as it is in the Messiah Chorus, makes the cadence even more convincing.

*But do I need to do anything else to make the plagal cadence convincing? Would a leaping bass make it more convincing like it does for an authentic cadence?*


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## EdwardBast

Often a final plagal cadence is preceded by a traditional V-I cadence which does the real work of bringing harmonic motion to a close. In such a case the plagal ending is usually just an ornamental extension or prolongation of the final tonic harmony and there is no need to worry about it being convincing. 

To use plagal motion for the final structural cadence of a common practice work is an uncommon thing to do and it will be difficult to make it sound like a convincing resolution. I would just experiment and see if you can find a solution that works.


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## millionrainbows

EdwardBast said:


> Often a final plagal cadence is preceded by a traditional V-I cadence which does the real work of bringing harmonic motion to a close. In such a case the plagal ending is usually just an ornamental extension or prolongation of the final tonic harmony and there is no need to worry about it being convincing.


Yes, exactly! You must have listened to a lot of Cajun and Zydeco music!


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## mikeh375

EdwardBast said:


> Often a final plagal cadence is preceded by a traditional V-I cadence which does the real work of bringing harmonic motion to a close. In such a case the plagal ending is usually just an ornamental extension or prolongation of the final tonic harmony and there is no need to worry about it being convincing.
> 
> To use plagal motion for the final structural cadence of a common practice work is an uncommon thing to do and it will be difficult to make it sound like a convincing resolution. I would just experiment and see if you can find a solution that works.


.........Amen....


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## mbhaub

Without that leading tone, making a solid, affirmative resolution to the tonic is one of the weaknesses, and beauties, of the plagal cadence. Berlioz sure did it convincingly (end of Symphony Fantastique movement 1). When I've written one, I like a long, unchanging pedal point on the tonic.


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## Bwv 1080

Dont go to church much?


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