Reaktor User Library - Crossover Filter
The Crossover Filter is a basic Reaktor tool for splitting an audio signal into two (or more) frequency bands. The bands can be processed separately and then added back together.
This video shows what the crossover filter is, how it works, and how to set it up. The filters used were built using the Audio EQ Cookbook by Robert Bristow Johnson.
The crossover filter can be used for a variety of purposes – they are often used for multi-band compression, for example, a very standard and powerful effect used in a lot of modern music. On the other hand, you can create strange and unique effects as well, like the pitch-shifter from the beginning of the video.