On the Interval Distribution page, toward the bottom, we pointed out that melodies tend to move downward in pitch using seconds, thirds, and fifths, but go upward in pitch using perfect fourths, sixths, sevenths, and octaves. For some reason, composers especially use a lot of “down” major seconds, but eventually make up for it by using “up” perfect fourths. Both of those intervals (major seconds moving down in pitch and fourths moving up in pitch) stand out for being used with a much greater frequency than the opposite (major seconds moving up or fourths moving down). This observation generally (though not exactly) holds true whether we count intervals in patterns every time they occur in a tune, or just once.
This is not true generally in the reverse. That is, composers as a group don’t go up in small intervals and then adjust downward in a big jump. A future project might be to see if there are any tunes that take this tack.
It’s clear that composers eventually have to employ some balance in their use of “up” and “down” intervals: If they did not, the music would end wildly far away in pitch from the starting point. Not only would singers find such songs unsingable, but even instruments have limited ranges and would such songs unplayable. (Orchestral music is an exception because the melodic line is often handed off to another instrument in a different register.)
But why do composers take frequent but small “down” jumps in interval and adjust with an occasional big “up” jump? Why not the opposite? And why such an emphasis on “down” major second intervals and “up” perfect fourths? We honestly have no idea. Perhaps the small downward jumps build a kind of musical tension that gets suddenly relieved with a large upward jump. But why not build tension by going up in small steps and coming down in large ones for release?
Eventually, we’d like to explore whether this observation remains true when we tease out individual time periods and genres. That analysis may provide us some insight to explain why composers in their melodies take frequent but short jumps down, and rare but big jumps up. That’s something to look forward to once the database has a sufficient number of melodies across time, genres, and countries.