FULL PATCH NOTES BELOW!
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Patch example to support episode 5 of Modular Podcast found here – https://www.youtube.com/watch?v=gXKRa7F2Xhk
PATCH NOTES
You won’t find a Polivoks High Pass filter (as far as I know) so why don’t we make one! Not with any DIY and circuit design purely with some patching. You can create a high pass filter with a low pass filter, multiple/copy of the dry input signal and an inverting mixer (or mixer and inverter). Here’s the patch …
The sound source is the Erica Synths Black Varishape VCO with an on board mix of it’s sub, saw, triangle and pulse (with some PWM from Mutable Instruments Peaks LFO mode). The VCO goes into the input of the Erica Synths Dtech Filter which is in low pass mode (only low or band pass modes). The output of the VCO is split and sent into the Sputnik Modular CV Processor (for the attenuverter i.e. level control and inversion) and the output of the Dtech filter goes into the CV processor as well. The CV Processor sends it’s output to Mutable Instruments Streams for some basic amplitude modulation with the onboard envelope and VCA. The excite input on Streams is struck by a gate from the Audio Damage Sequencer 1.
You first hear the low pass output with manual movement of the filter cut off slope, filter cut off frequency, resonance and resonance response curve on the Dtech. The dry signal is mixed in and inverted on the CV processor and tweaked until the level cuts out the low frequencies and it creates a high pass. This is due to phase cancellation between the low pass output and dry signal as filtering creates phase shifts. Some bleed is still apparent but with further tweaks you can eliminate most of it. Manually playing with the dry inverted signal level we can blend between low pass and high pass style filtering.