Theme and variation is a way in which a composer has a given theme in which to base the composition on, almost like a motive. Once this motive is set the composer can than variate the theme accordingly such as through:
Augmentation & Diminution:
‘ In melodic parts, the respective lengthening and shortening of the time-values of the notes. Thus, in a fugue, the subject may (epescially towards the end) appear in longer notes, a device which adds dignity and impressiveness’
(Kennedy, 1996, p31)
This use of rhythmic variation is a extremely strong way of making melodies stick out, giving the piece a “freshness” and direction that is based around a given theme. Of course there are other ways to variate a theme this can be done through, medoly variation, instrumentation and timbre. With this in mind the below videos are from Danny Elfman showing how just from variation a rhythm the melody can take the composition through different transistions.
The Simpsons Theme
(I tried to find one with the video to match the theme, but most of the youtube ones were poor quality recorded on camera!)
The variations upon this theme are very simple often reflecting what the actions of the simpsons characters are doing. This creates a composition that reflects the actions of screen, a fantastic example of making the music contextualized! Throughout the video the notes of the melody shortens and lengths often with the same melody in mind. This is a classic example of how Danny Elfman has created a theme and variated accordingly and obviously throughout the track. In some cases there are elements where the theme is changed completely in terms of melody and rhythm often using using the same notes just re-arranged with a different orchestra texture.
Broken down into melodic segments, the last post shows how different parts of the melody re-arranged into shorter or longer melodic parts for the theme The Batman. Compared to the Simpsons tune the Batman offers much less subtle variations often that can only be heard through careful hearing. To me what strikes as a fantastic tool is the repetition of the melody often done with another instrument. The repetition re-enforces the theme often disguised behind layers of other orchestrated parts.
Kennedy, Michael (1996). The Concise Oxford Dictionary of MUSIC. 4th ed. Oxford: Oxford University Press. n/a.