Building a Synthesiser - an introductory tutorial for Reaktor v5.

Symple Synth: Filters

Now we're going to use part of a built-in filter macro to provided us with a low pass filter.
1.Right click and select Macro>_New 2in2out and use its properties box to rename it to Lo Pass Filter.
2. Open the new macro's Structure Window and delete one of the outputs. Rename the other output to Out and rename the inputs to In and Env (we're going to tie the filter to amplitude by shaping it with the amplitude envelope; yes, you could give it its own envelope generator but then the Symple Synth would be less simple).
3.Right click and select Built-in Module>Filter>Multi/LP 4-Pole FM from the confusing array of filters. You'll probably need to go and read up about filters at this point.
4. Wire the Macro's input to the 4-Pole filter's In. Create Controls for Cutoff (you'll rename this from P-Cutoff when you Create Control) and Reson[ance] and wire the Env input to the 4-Pole filter's F (linear Frequency) input. Take the output from the filter's LP4 (low pass) output.
5. Now all we need to do is wire our filter macro between our Mixer output and audio collector and wire a third Out (highlighted) from the Amplitude Envelope to the filter's Env input...
6. ...and tidy up the Panel. The graphic display of the filter curve can be enabled in the VIEW panel of the 4-Pole Filter; check Visible, uncheck Show Label and size it to 90 x 90.
Let's give the sound some warmth with a Low Frequency Oscillator