What's it called when you play the same exact melody with a different rhythm?

Question

As an example, here is the original iconic melodic phrase that's used throughout the Trails Sky games:

https://youtube.com/embed/3GB-xej4GFc?start=66&end=85

But here in this next piece, the exact same melody is used with a more upbeat "jazzy" rhythm (certain notes are shortened and pauses are inserted):

https://youtube.com/embed/cY_WTw4_rEA?start=50&end=80

Is there a name for this general technique? Or is there a name for the particular "jazzifying" done in this example?

Answer 1

At least colloquially, this is known as rhythmic variation.

A Google search at the time of this post results in the following websites and uses of the term "rhythmic variation" to mean using the same (or a similar) melody with a different rhythm on the first page of results:

https://hellomusictheory.com/learn/theme-and-variation/

Rhythmic Variation

The third main thematic variation is the rhythmic variation.

This is when you keep the harmony and melody mostly unchanged but you break the rhythmic pulse of the piece and create syncopation.

https://truefire.com/jazz-guitar-lessons/123-jazz/step-2-rhythmic-variation-subtle-rhythmic-articulations/v10788

Step 2. is to add rhythmic variation to the melody. This is a simple concept of changing the length of the notes that make up the melody, playing the note twice instead of once, or playing on the upbeat rather than the downbeat. Experiment by playing some notes of the melody longer and some shorter.

https://www.guitar9.com/column/practicing-scales-rhythmic-variation

It is important to practice scales with different rhythmic variations, such as eighth notes, triplets, sixteenth notes, sixteenth notes triplets and thirty second notes. This will make it more interesting than just practicing the same rhythm all the time.

http://www.samueljpost.com/the-music-post/there-are-more-syncopated-variations-a-mathematical-music-theoretical-exploration-of-rhythm-part-1

there are 9 notes in the idea, and they occur over 12 beats (2 measures with 6 beats each). That means there are going to be 3 "empty" beats without a note beginning on them. Making a choice of a purely rhythmic variation for the 9 notes is equivalent to choosing which 3 beats will be empty.

Answer 2

I would propose that this is an example of thematic development. Especially since your example comes from a soundtrack, it's pretty clear that this type of development is ultimately based in the development of Leitmotive that dates back to Wagner and earlier.

Thematic development, in its most broad sense, can be any variation of a theme. It can be varied harmonically, rhythmically, texturally, etc., and it can either be varied in full or can be fragmented into smaller sections that are then developed (something we call fragmentation).

I think it's important that you say the entire melody is being changed. This is why I would call this thematic development as opposed to motivic development, which typically handles smaller cells as opposed to larger melodies.

Answer 3

There's not a specific name for the technique, but it's a common tool, particularly in soundtracks, to create associations between different aspects of the story, characters, etc. Transforming melodies, rhythms, instrumentation, and other aspects of musical material to change the feel of the music is a compositional technique that goes back — as an expression — for as long as there have been composers.

With regard to rhythm specifically, there are two "named" techniques, though they don't apply to the examples given.

• augmentation is the technique of proportionally elongating a rhythmic pattern;
• diminution is the technique of proportionally shortening a rhythmic pattern. In both cases, the melodic material can stay the same, changing only the rhythm.