Some Fun with Contrary Motion


Forte's set number 6-z6 can be played as C-C#-D-F-F#-G, which doesn't look like much. I found it today while trying to capture a bit of Sorabji's style and got some nice vocabulary ideas from it on the theme of intervals moving in contrary motion.

One way to think of 6-z6 is to start with what I call a Lulu chord, which is a fifth with a fourth nestled inside it -- for example, C-G paired with C#-F#. To turn it into 6-z6, continue the process one more step by squeezing a minor third (in this case D-F) into the middle.

This way of thinking of it encouraged me to make lines using contrary motion, moving the 6-z6 cell up in steps of a minor third to create a rising chromatic scale as the top line with a zigzagging line underneath. The basic cell of this idea is shown here, playing the intervals simultaneously and also broken (which sounds great in the left hand on piano, by the way):

I was led to this while listening to the Toccata from Sorabji's Opus Clavicembellisticum, which you can check out here -- listen for the lines that rise or fall with a an opposite, "tugging" contrary motion similar to the patterns above. Playing the simple pattern above on the piano with both hands some interval apart produces somewhat similar effects that shift between pure consonance (open fifths) and extremely sour dissonance almost like the phasing effect of a Steve Reich polyrhythm:

The complement of 6-Z6 is Eb-E-G#-A-Bb-B, which is a similar thing but different. This is Forte 6-Z38,and Stockhausen used this pairing in the first movement of Tierkreis, a light and tuneful piece that shows more of the melodic potential of these chromatic-looking sets of notes:

We can think of 6-Z38 as an augmented fifth (Eb-B) with a tritone (E-Bb) inside it and a minor second (G#-A) rattling around awkwardly in the gap. However, this doesn't lend itself to the same trick: instead we will "cheat" by replacing the minor second with a major third (F-A) that fits perfectly, and this allows us to perform the same trick again but with quite a different sound:

This one is Forte number 6-7. Combining 6-z6 with 6-7 a minor third above it almost covers all twelve notes; not quite, because we messed it up but I think it's worth it.

I don't have much more on this -- it goes into the category of cheap tricks or hacks that might help you find new and interesting things on your instrument, so there's no need to take it too seriously.

I'm aware I haven't posted much of late; earlier this year I started a day job (!) and while I play every day I've been taking a bit of time off composing or other music-making that demands time and thought. I'll be back, though.