Our Pseudo-moog

The monophonic version of our algorithm (CC24 = 9) brings out the full potential of our synth, and is much more involved than any of the previous algorithms, combining three oscillators with a pitch-tracking four pole resonant filter to make an efficient monophonic subtractive synth, with filter cutoff that can be altered smoothly in realtime. This algorithm is meant to loosely approximate the original minimoog synthesizer. The currently limited number of oscillator configurations (CC25) are based on diagrams in the original minimoog patch book. More variations may be added in future firmware updates.

Monosynth Controls

The monophonic synth CCs share some core things in common with the first two algorithms so that switching between algorithms on the fly remains fairly intuitive, though there are some important differences to keep in mind, as follows. The FM frequency knobs now control Filter Cutoff (CC20) and Filter Resonance (CC21). Note that if Filter Cutoff is set to zero, no sound will be heard. Envelope 2 controls remain the same, with Envelope 1 now applying to the Filter, but without the Depth parameter, since this is handled by Cutoff and Resonance. For a sustained sound, set the Decay parameter of Envelope 1 at or near to zero. Higher values will result in more quickly decaying increasingly percussive sounds. The Wave Parameter (CC26) controls the “Duty Cycle” (pulse width) of the waveform, or switches it to sawtooth with a value of 0. “Detune” alters the first two oscillators (for details, see under the heading Detune above). Since this is not a wavetable algorithm, the selection of waveforms used in algorithms 1 and 2 are not available. Instead, “Waveform Select” (CC25) becomes “OSC Config” and controls the behaviour of our three oscillators. Values 0 through 3 apply to the third oscillator only, changing its behaviour as follows: 0 = unison, 1 = down a 5th, 2 = down an octave, and 3 = down two octaves from the other two oscillators. Values 4 and 5 optionally turn off 1 or 2 of the oscillators for a leaner sound: 4 = third oscillator off, 5 = oscillators 2 and 3 both off. Arpeggiator, LFO rate, and portamento behave as expected; however, a significant difference to the other algorithms is that the LFO rate applies to not just one but two kinds of modulation, normal LFO and Pulse Width Modulation (PWM). The latter gives a sweeping or flanging effect, as it changes the duty cycle according to the LFO frequency. For the uninitiated, using PWM and Modulation together can be a bit tricky at first, with results that can be quite subtle. We recommend first setting the PWM control to zero, then adjusting the Modulation control. Conversely, to try out PWM, first set the Modulation control to zero. Once you get used to controlling each independently, mixing them will be easier.