In this video, the coefficients for a low pass biquad filter are calculated. This filter is based off of the Audio EQ Cookbook by Robert Bristow Johnson, which can be accessed here: http://www.musicdsp.org/files/Audio-EQ-Cookbook.txt
This series explains the very basics of filter design and terminology. We'll be keeping things as simple as possible, and laying the groundwork for much more complex subjects such as oversampling filters, zero delay feedback filters, embedded saturation, and more. So stayed tuned for much more on the subject of filters in Reaktor!