Eurorack Reference / modules /verbos/harmonic-oscillator audit site v0.1 — milestone 3
verbos/harmonic-oscillator

Harmonic Oscillator

Verbos Electronics

Discrete all-analog triangle core VCO with outputs for saw, square, triangle and each of the first 8 harmonics, plus a voltage controlled mixer for mixing the harmonics to create evolving timbres.555

Capabilities 4

Additive Synthesisadditive-synthesis
Sum-of-sines additive voice — the 8 sine harmonic outputs plus the per-harmonic VCAs and the harmonic mixer realize additive synthesis directly in the analog domain.555
Harmonic Oscillatorharmonic-oscillator
Outputs the first 8 harmonics of the fundamental as individual sine waves, plus standard triangle / sawtooth / square taps. Each harmonic amplitude is independently CV-controllable; the on-board voltage-controlled mixer combines them via scan / tilt / mix CVs into a single mixed output.555
Voltage Controlled Mixervoltage-controlled-mixer
On-board VC mixer combines the 8 harmonic VCAs into a single mixed output, with scan (which harmonic is loudest), tilt (spectral skew), and mix (overall blend) all CV-controllable.555
Voltage-Controlled Oscillatorvco
Discrete all-analog triangle core VCO ranging 3 Hz to 20 kHz with 1V/oct, linear FM, and exponential FM inputs.555

Jacks 26 — 14 in / 12 out

NameSignalVoltageDescription
Inputs (14)
1V/OctcvCalibrated 1V/octave pitch CV input.555
1st CVcvCV input controlling the level of the 1st harmonic in the mixed output.555
2nd CVcvCV input controlling the level of the 2nd harmonic in the mixed output.555
3rd CVcvCV input controlling the level of the 3rd harmonic in the mixed output.555
4th CVcvCV input controlling the level of the 4th harmonic in the mixed output.555
5th CVcvCV input controlling the level of the 5th harmonic in the mixed output.555
6th CVcvCV input controlling the level of the 6th harmonic in the mixed output.555
7th CVcvCV input controlling the level of the 7th harmonic in the mixed output.555
8th CVcvCV input controlling the level of the 8th harmonic in the mixed output.555
Mix CVcvCV input for voltage-controlled overall blend/mix of the harmonic mixer output.555
Scan CVcvCV input for voltage-controlled scanning of the harmonic center/width position.555
Tilt CVcvCV input for voltage-controlled tilt (spectral balance) of the harmonic mixer.555
c.v. inputcvExponential FM CV input; routed through a reversing attenuator before exponential pitch modulation.555
f.m. inputcvLinear FM input; routed through an attenuator before reaching the frequency modulation path.555
Outputs (12)
1staudioSine wave output for the 1st harmonic (fundamental).555
2ndaudioSine wave output for the 2nd harmonic.555
3rdaudioSine wave output for the 3rd harmonic.555
4thaudioSine wave output for the 4th harmonic.555
5thaudioSine wave output for the 5th harmonic.555
6thaudioSine wave output for the 6th harmonic.555
7thaudioSine wave output for the 7th harmonic.555
8thaudioSine wave output for the 8th harmonic.555
MixedaudioVoltage-controlled mixed output of all 8 harmonics combined via the harmonic mixer.555
SawaudioFundamental sawtooth wave output from the oscillator core.555
SquareaudioFundamental square wave output from the oscillator core.555
TriangleaudioFundamental triangle wave output from the oscillator core.555

Parameters 14

NameTypeRangeBehavior
1st harmonic levelfader555
2nd harmonic levelfader555
3rd harmonic levelfader555
4th harmonic levelfader555
5th harmonic levelfader555
6th harmonic levelfader555
7th harmonic levelfader555
8th harmonic levelfader555
c.v. attenuatormenu_settingReversing attenuator (attenuverter) on the exponential FM CV input; routes the signal to exponential pitch modulation with polarity control.555
centermenu_settingSets the center position of the harmonic scan window, sweeping which harmonics are active like a bandpass filter.555
f.m. attenuatormenu_settingAttenuates the linear FM input signal on its way to linear frequency modulation of the oscillator.555
Frequencymenu_setting3Hz – 20000HzSets the oscillator frequency from 3 Hz to 20 kHz.555
tiltmenu_settingSpectral tilt control: turned up favors higher harmonics and reduces lower ones; turned down favors lower harmonics and reduces higher ones; centered has no effect on the harmonic mix.555
Zones
Low harmonics favored
High harmonics favored
  • Low harmonics favored -100–0%Turned down favors lower harmonics and reduces higher ones.555
  • High harmonics favored 0–100%Turned up favors higher harmonics and reduces lower ones.555
widthmenu_settingControls the width of the harmonic band selected by the center control, sweeping harmonics across like a bandpass filter.555

Firmware history 0 versions

No firmware history recorded.

References 2

  1. [555]
    Verbos Harmonic Oscillator Tech Cardmanual
    verified 2026-05-19
  2. [556]
    Verbos Harmonic Oscillator product pageproduct_page
    verified 2026-05-19