The Harvestman - Hertz Donut MkII


The Hertz Donut is a dual digital oscillator. It consists of a main oscillator and a modulation oscillator. Due to internal connections FM and AM between the two oscillators is done very easily. Pushbuttons allow for different routing and tracking options and wave selection.
Besides linear FM there is also possibility of true thru-zero FM which will expand sonic capabilities even more!



The Hertz Donut MkII consists of two identical digital 16Bit oscillators, a digital waveshaper and an internal modulation matrix.
Both VCOs have an output with three alternate Wavefrms (sine, triangle, sawtooth) and a pulse output.

Additionally there is a 1V/octave input (0-8V), an exponential CV input (0-5V) and a Thru-Zero linear FM input (bipolar, 10Vpp). The latter two sockets share a common polarizer. besides this we find for each VCO a sync input and the range button, activating the LFO mode.

The upper VCO, the primary oscillator, is followed by a digital waveshaper called Discontinuity, offering three different shaper types. The discontinuity parameter is voltage controllable (0-5V).

Tracking parameter: the modulation oscillator can follow the primary oscillator's pitch and it's possible to add a frequency offset with both the potentiometer and a CV (0-5V). This is areally outstanding feature in combination with the Thru-Zero linear FM as the frequency ratio between both digital VCOs can remain constant this way.

Between both oscillators' outputs a socket is located, carrying a logic OR betweeen both oscillators. Pretty nice for weird noisy square sounds!

Modulation Bus determines how much the modulation oscillator affects certain parameters. Modulation destinations are primary oscillator's pitch (P. FREQ), the discontinuity parameter of the waveshaper, the tracking and the main oscillator's level (AMP); more than one destination can be activated simultaneously. The amount of modulation is set with the potentiometer and a CV.


per oscillator:
inputs 1V/octave, exponential CV, linear CV, sync
outputs: variable output (sine, triangle, sawtooth), square output

Discontinuity CV in, Tracking CV in, modulation Bus CV in, OR output


3U Eurorack module, 17HP wide, 30mm deep

0.166 kg
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