Coloured Noise PUBLIC

Filters for converting a white noise source into Pink, Brown and Violet noise from 10Hz to 1MHz.

This is an example to test parameters for filters to convert white noise into: pink noise - -10dB/Decade, brown noise: -20db/Decade, violet noise: +20db/Decade. Not yet included is Blue noise at +10dB/Decade.

The pink noise filter comes from an idea given in the inimitable "The Art of Electronics" (Horowitz and Hill). I have added a couple of extra poles to flatten the response up to 1MHz.

I have tested a simple white noise generator using the old reversed biased transistor avalanche and get a nice 'flat' (flat is a difficult concept with noise) white noise source up to about 3MHz with the first stage of this circuit.