Zlob Modular

Notes: The Foldiplier is a 4hp odd/even harmonics generator with 2 different oscillating feedback paths. The folding core of the design originates from the odd harmonics (middle)section of the Serge Wave Multiplier. But the Foldiplier adds voltage control over the symmetry and offset as well as a switch for feedback, jumper selectable between, a transistor based oscillating fuzz inspired by the Hemmo Bazz Fuss with a lot more low harmonic content and a passive oscillating half wave rectification circuit with more high harmonic content. When these feedback oscillations mix with an incoming waveform some unpredictable and unique nonlinear timbres can be achieved. The module can also be used as a no-input experimental oscillator with the feedback switch engaged. All diodes in the module are silicon.

The Fold knob controls the amount of times the waveform is folded in on its self (indicated by the red led window below the knob). The C.V. knob below is an attenuator for incoming control voltage corresponding to the Fold jack(indicated by the red led window above the jack, it only responds to positive voltage). So, the Fold knob acts like an initial amount of folding depending on its position. For example, with the Fold knob fully clockwise you can get even more folds with a control voltage in at the Fold jack. The Offset knob controls how much positive DC voltage(0 to 5v, clockwise) or negative(0 to -5v counter clockwise) DC voltage(indicated by the led window above the Offset jack, red for positive, yellow for negative) injected into the waveform via the Symmetry knob. With the Offset knob position at noon(0v) there will little effect from the Symmetry knob. The Offset jack is expecting +5v to -5v with knob position at noon to scan through the positive and negative voltage. The Symmetry knob controls the amount of negative or positive offset voltage(dependent on the Offset knob) mixed with the waveform(indicated by the yellow led window above the Symmetry jack). If positive voltage is mixed with incoming waveform more folds will occur on the positive troughs of the waveform, likewise, when negative voltage is introduced more folds happen on the negative troughs. This part of the circuit can also be broken down by thinking of the Offset as a voltage controlled crossfader swinging between positive and negative voltages into a VCA controlled by the Symmetry knob and jack. When a voltage is present at the Symmetry jack the Symmetry knob becomes an attenuator. The Symmetry jack only responds to positive voltage.

Width: 4hp
Panel Material: Double Sided PCB panel with Classic and Soulless
Reverse Power Protected
Current Consumption: +12v: 40mA, -12v: 35mA
Depth: 47mm or 1.75"
All through-hole build
Ships with M3 black nylon screws
Expandable: No

Notes: The SVF is a 4hp 2 pole 12dB State Variable Filter Eurorack Module available as a Eurorack DIY Kit, PCB and Panel, or Built Module.

It provides Low Pass, Band Pass, and High Pass outs inspired by WASP and Thomas Henry filter topologies. The filter has 2 audio inputs, but channel 2 is jumper selectable between standard audio in or Ping-able operation. The 2019 revision also adds improved cutoff and resonance response and attenuversion through the ACV IN using the above pot. CV IN provides another unattenuated voltage input to modulate the frequency.

At the CV in, +10v will open the filter completely if the cutoff pot is CCW(counter clockwise). With the cutoff knob at noon the filter can be opened with +5v or closed with -5v. CV input at the ACV in is dependent on the CV attenuverter knob.

There are also several jumper selectable modes for max resonance, self oscillation or no oscillation based on the setting of the resonance pot. According to the jumper configuration, the filter is capable of clinical and clean, to juicy and drippy, to low pass gate sounding plonks, to screaming chaotic resonance. When set to self oscillation mode, the filter can produce a sine like wave with no input and a trapezoid like wave in the max resonance jumper setting. In max resonance mode, the filter output can exceed 10Vpp. On the newest version, there is a trimmer on the top pcb to set the lowest cutoff frequency.

The new black and white pcb/panel is reversible meaning, one side is classic (first picture) and the other side is soulless (second picture).