Ingredients: 2 VCO/LFOs, Mult, Mixer with polarity control, 700 Dual Router
Notes:
Patching:
VCO/LFO 1 Sine or Triangle to Mult 1
Mult 1 to 830 Mixer IN2 (or Oakley Multi-Mix) and 700 IOA
VCO/LFO 2 Sine or Triangle to Mult 2
Mult 2 to 830 Mixer IN3 (or Oakley Multi-Mix) and 700 IOB
830 Mixer OUT1 to 700 CV IN
700 IOX out to filter or rest of circuit path
Controls:
VCO/LFO frequency to taste
830 Mixer IN2 to full positive gain
830 Mixer IN3 to full negative gain
700 Router Mode equals "VOLTAGE"
700 Router Switch knob to zero
The 700 IOX output is the maximum of VCO/LFO 1 and the minimum of VCO/LFO 2,
switching where the waveforms have a common crossing point.
Mixing VCO/LFO 1 & 2 at opposite polarities gives zero at the point where
the two waveforms are identical voltage levels. Using the mixed result as
the control voltage source to trigger the 700 router creates transitions
that are nearly at the zero crossing of the two waveforms, irregardless of
the frequencies of the two waveforms. Tweaking the mix and control so that
no glitching occurs seems impossible, possibly due to delays in the control
path. However, a little filtering takes any short term glitches away.
Mixing two VCOs creates interesting cross modulation inharmonics. Mixing
two LFOs creates a modulation source that jumps between two modes.
Control/Mix levels on the mixer and the 700 Switch knob give more drastic
cross modulated results.
Using two sources such as VCOs through two different resonant filters may
provide more interesting results.
John Loffink
The Microtonal Synthesis Web Site
http://www.microtonal-synthesis.comThe Wavemakers Synthesizer Web Site
http://www.wavemakers-synth.com