Chapter 8: Signal Modifiers | VCA

⚛ VCA is a voltage controlled amplifier, although it normally attenuates, rather than amplifies.

⚛ Additional Information

⚛ The following is a transcript of the narration:

✸ Signal Modifiers: VCA

✸ VCA uses a voltage controlled input to adjust the level of any signal, sent through it.

✸ VCA is an analogue multiplier and a level control.

Patch 5 VCA

⚛ The following is a transcript of the narration:

✸ Patch 5 VCA

✸ Connect sawtooth wave output to VCF input. 

✸ Send Low Pass output to VCA audio input 1.

✸ Open signal in and gain on the VCA, Cut Off on the VCF and Tune on the VCO. 

✸ Find the timbre that you like.

✸ Set VCO 1 to LFO mode and connect it to the Envelope Generator gate input. 

✸ Output of the envelope connect to VCA external control voltage input.

✸ Send the control voltage signal in. 

✸ Adjust Cut Off, Attack, Decay, Sustain, Release, Time Range, and LFO rate until you hear "beat-like" sound.

✸ Adjust the timbre of the sound with VCF to hear available range of frequencies. 

✸ Change the tone to your liking.

✸ This method is required to create periodicity in the constant unchanging tone. 

Patch 6 VCA

⚛ The following is a transcript of the narration:

✸ Patch 6 VCA

✸ Connect sawtooth wave output to VCF input. 

✸ Send Low Pass output to VCA audio input 1.

✸ Find the timbre that you like.

✸ Set VCO 1 to LFO mode and connect it to the Envelope Generator gate input. 

✸ Output of the Envelope send to CV input of the VCA.

✸ Adjust the Envelope and LFO parameters until you hear the Envelope shaping the waveform. 

✸ Here we are using VCA to apply the shape of the Envelope to the loudness of the audio signal.

Bonus Patch

✸ Bonus Patch 

✸ While saw tooth waveform is sent to VCF -> VCA chain, use the splitter to multiply LFO output.

✸ Feed both VCA CV input and Envelope Gate with LFO. 

✸ Connect output of EG to Cut Off CV input of the VCF.

✸ Play with LFO rate and Envelope to create "Skrillex-type" of sound.