Designing Sound in SuperCollider/Rain

Fig 38.1: Fluid sphere impact
The waveform produced by impact of fluid sphere on hard surface - we'll create it as a Function here so we can reuse it:

Fig 38.3: obtaining a Gaussian noise distribution.
The Central Limit Theorem tells us that adding together independent noise sources will eventually give us gaussian noise. Twelve is certainly enough for auditory purposes.

In the book, Andy says that it is more efficient to use two white noise sources and to create a gaussian shape using the Box-Muller transform. However, this involves some relatively heavy mathematical operations (log, cos, sqrt) so it's not actually obvious which approach is more efficient on a given system. Compare the CPU usage (and the audio result) of the above, with the following: