Xen12

This is a project to make especially consonant and natural-sounding timbres whose scales fall on the standard 12 tone piano spacing.

All wav files can be generated by running xen12synth.py The sfz files work with any sfz player

The generated timbres are numbered 15, 12, and 10. They work by stretching or squeezing the second harmonic to the number of half-steps in the timbre number, then snapping to the nearest piano note. These timbres were picked out because they require especially small amounts of snapping.

It turns out that human ears will perceive a series of harmonics as a single note if they correspond to the standard harmonic series with all harmonics brought to the same exponent. In this case the 12 brings everything to the 12/12=1 power so it's very close to the standard series, although the snapping to piano positions makes it notably more consonant particularly on the tritone. The 15 timbre has overtones at 1^(15/12), 2^(15/12), 3^(15/12), etc. It has a very round sound. The 10 timbre is squeezed rather than stretched which is something physical objects never do when they make sound so the human ear is less accepting of it. It has a concave sound which sounds fractured and about to break into multiple notes but it's aligned so well that it's still harmonious. Minor chords with standard timbre have a bit of this effect.

Individual harmonics are made beatless but fuzzed by modulating the frequency with adding gaussian noise. Other tricks used to make a nice sound are described in the code. A standard-sounding but still very sweet synth sound could be made by using the 12 timbre without snapping the harmonics.