[sdiy] Decent 2 pole linear filtering with f32

[Andrew Simper]

This may be of some use to people using sharcs or ti or other single
precision floating point devices, and it may even work well for fixed
point too. I used trapezoidal integration on the ideal linear svf
structure, and then optimised the parameters a bit to keep the noise
down below < -110 dB at pretty much all cutoff frequencies. The
algorithm is pretty easy to implement, and has the best quantization
error and coefficient error of any other linear 2 pole filter
structure I know of (but happy if people know of something even
better, please share):

http://www.cytomic.com/technical-papers

All the best,

Andy
--
cytomic - sound music software