I am pretty sure that from a point of theoretical DSP purity, low pass filters built using the "RDFX" instruction would generally be of the form:
Code: Select all
RDFX 33,factor
WRAX 33,(1 - factor)
However, in most supplied Spin examples, since factor is much smaller than 1 for many cases, (1 - factor) is simply replaced by 1.0. I'm sure the response is not very far off. But why not make it correct?