On Tue, 29 Sep 2009, Chris McCormick wrote:
Thx hard off! I have found a good way to get appealing melodies is to have a bit of fractal stuff going on. One way to do this is to have the same melody at different speeds (double speed, half speed, triple speed, quadruple speed) laid over the top of eachother, and then switch randomly between the normal speed melody and the other speeds. It means you get melodies which are internally self similar and for some reason the brain likes that (well my brain does anyway).
Hmmm, can this be called self-similar? well, if you do have speeds 0.5, 1.0, 2.0 and 4.0 at once, then doubling the speed of the whole thing will cause the speeds to increase speeds to 1.0, 2.0, 4.0, 8.0, so with 3 out 4 speeds (or 3 out of 5) the system displays a large amount of approximative self-similarity, but if you add 3.0, 5.0, etc. then depending on which ones you actually choose, it may match much less. Usually, it's called self-similar when the whole thing is equal to a simply transformed (e.g. uniformly scaled) version of itself, but I'd gladly extend it to not-exactly-equal things as well... as long as it's more equal than non-equal...
In general, exact powers are a key concept in getting more self-similarity... so for example, you could use just a bunch of powers of two, but if you do use three as a multiplier, use it multiplied by each of those powers of two, and also use many powers of three multiplied by each of those powers of three. This would be more self-similar but it doesn't mean that it'd be any easier to follow. It seems that powers of 2 are a lot, lot easier to think about than powers of 3, 5, 7, ...
otherwise, there's not just self-similar patterns that stimulate the mind: also perfect harmonics do (just intonation, etc). so if you use the speeds 0.5, 1.0, 2.0, 3.0, 4.0 at once, it's like using the harmonics 1,2,4,6,8 at once in a timbre, or like making a chord of four consecutive fundamentals and a fifth. (actually, unrolled, that's degrees I, VIII, XV, XIX and XXII).
On a related note (pun intended), music history started with a predominance of just intonations, because that's what struck a c(h)ord in the mind at first, because it's made of perfect harmonics, but then the less-harmonically-perfect equal-intonation has largely replaced it, because equal-intonation is more self-similar than just-intonation is! Here, self-similarity is important because it allows transpositions of the same melody to appear more closely related.
Hoping that those ideas will in turn give you some ideas of how you could tweak your list of speeds, or come up with any other new concepts.
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