Process on soundfont creation

In the polyphonic case, most effects are never interrupted, we just play them out.
However, we can always start another clash/blast even though the first one isn’t finished yet, assuming there are still wav players available.

In the monophonic case, each effect becomes the new hum as soon as it’s started, so it can always be interrupted by another effect. In some cases we limit the number of interruptions per second though, since playing a new clash 20 times per second just becomes noise.