The Hertz Donut mkIII is a powerful digital complex oscillator with detuned unison, a 3x4 modulation matrix and even an external input. The primary oscillator creates a basic waveform by controlling three parameters in addition to frequency: Phase Distortion, Umbrage, Resonance. In addition, two modulation oscillators (operators) can be used to modulate these parameters to produce a wide variety of sounds. You can also memorize the settings of modulation combinations as presets, and morph between presets or save them. It can produce bassline, stone, glass, steel-like sounds, and industrial mechanical sounds.
Other features include:
Synthesis that fully utilizes FM and Phase Distortion
8V / Oct input to withstand 1 octave changes
Uses Thru Zero FM, which extends the definition of FM by inverting the waveform at frequency <0.With external FM input
Modulation matrix settings using sliders
Parameter selection using buttons
Easy-to-understand 128x32 OLED display can display modulation information and menu settings in addition to scale and frequency
Two internal sine wave operators that can be used for modulation can quantize or lock the frequency ratio to the frequency of the primary oscillator
96kHz sample rate
How to Use
Primary Oscillator Section
The Primary Oscillator section controls the basic settings of the main output oscillator waveform. Use the coarse frequency knob and fine frequency knob to set the base frequency. In addition to frequency, you can set three parameters through the Fold knob: Phase Distortion, Umbrage, Resonance. After selecting a parameter from the Fold Select button, set it with the Fold knob. If you select another parameter, the value of the previously controlled parameter will be locked, but can be controlled using CV. Which of the three parameters is controlled by Fold CV can be set from CV Destination in the oscillator menu.
You can access the oscillator setup menu by holding down the encoder and pressing the Fold Select button.
Octave: Shifts the oscillator frequency by ± 2 octaves, in 1 octave increments
Unison: Set the presence or absence of unison and detune (You can also adjust the detune by holding down the encoder and pressing the OP B button)
CV Dest: Select the Fold parameter controlled by Fold CV from Phase Distortion, Umbrage, Resonance.
Modulation Operator Section
The Hertz Donut Mk3 is equipped with two oscillators (operators) whose main purpose is modulation, and each operator can apply modulation to four parameters without patching and save the settings as presets. The amount of modulation for each parameter is set in the Modulation Mixer section below. In addition to the Course Tune / Fine Tune knobs, the A and B operator sections are equipped with 2V / Oct input, FM input with attenuverter, and menu buttons used for operator settings and Modulation Matrix settings.
The operator's menu can be accessed by holding the encoder and pressing the operator button. From the menu, the operator's frequency mode can be selected from the following.
Quantize: Select whether to quantize the frequency of the operator with the frequency of the Primary Oscillator. When quantized, dissonance is unlikely to occur with various types of modulation, and you can apply modulation while maintaining the pitch. When quantized, the operator's Course Tune knob controls the frequency ratio of the Operator and Primary Oscillator. The Fine Tune knob allows the frequency to be continuously shifted from that frequency, allowing the operator's frequency to be slightly offset from the integer ratio.
Follow: Although it does not quantize, the operator's Coarse Tune knob does not control the absolute frequency, but rather the frequency ratio between the operator and the primary oscillator. Since it follows the frequency change of the primary oscillator, it has the effect of keeping the tone constant even if the frequency changes.
Free: The frequency of the operator is a mode that is independently determined regardless of the primary oscillator.
AB Link: The mode in which the frequency of operator B follows the frequency of operator A
External Input Operator B does not have a 1V / Oct input, it has an External Signal Input instead. The signal input here is treated as one of the modulation sources in the Modulation Mixer section described later like the operator, and can be used as an internal modulation source for each parameter, and the modulation amount can be saved in the preset.
You can also press the Ext IN button while holding down the encoderGlobal options menuOpens, and you can reverse Coarse / Fine knob assignments, set preset CV, and set AUX Output.
Modulation Mixer Section
In the Modulation Mixer section, you can set the amount of modulation applied to four parameters from the three sources of Operator A / B and External In signals. First, decide the modulation source you want to set, press the corresponding button, and use the sliders to adjust the amount of modulation to the four modulation destinations. The large "MOD" knob becomes the master control for all modulation amounts, so turn the knob all the way to the right before setting. If you then select a different modulation source, the modulation amount of the previous modulation source will be locked.
The modulation destination is basically as it is on the panel. For Operator A, "Operator Frequency" is the modulation amount from Operator A to the frequency of Operator B. Operator frequency modulation tends to produce chaotic results, so a small amount of modulation may be better controlled. When the EXT IN modulation amount is set, "Operator Frequency" is the OP A modulation amount, "Phase Distortion" is the OP B modulation amount, and internal modulation cannot be performed from EXT IN to Phase Distortion.