A simple noise generator and 4 band fixed filter bank. The noise is normalled to the Filterbank input. The cutoff frequencies are matched to the Bark Filter, so that 3 bands of the Bark Filter correspond to 1 band on the Noise & Filter. It is a small and quick noise source and pairs well with Scan & Pan and Amp & Tone.
The Noise Generator
The bottom most jack is a pink noise output. This is generated by a 23 stage Pseudo Random Sequence Generator. Though technically not random, it takes many minutes to repeat. It uses digital filtering to make the signal content roughly equal in all octaves, or Pink Noise. This type of signal is usefull for making percussion sounds as well as noise beds and sweeps. The Noise output is normalled to the Filter Bank input.
The Filter Bank
The Filter section of the Noise & FIlter is a 4 band fixed filter bank. When a signal is patched into the filter input, it goes to all 4 filters. Each of the filters pass only the signal in the their range. The band frequencies are on the Bark Scale. So, if the 12 bands on a Bark Filter were divided into groups of 3, they would be the 4 bands in this filter. Below 630Hz, from 630Hz-1.7kHz, from 1.7kHz to 4.4kHz and above 4.4kHz can be thought of as low, low-mid, high-mid and high frequency ranges. The real power of this simple module is released when it is patched together with other modules. The bands can be mixed, faded between and panned using a Scan & Pan, for instance. The filter is also quite interesting when used in the feedback path on the Multi-Delay.