Red Roland SH-101 with Mods

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"THE MODS INCLUDE:
VCF FM controls – Essentially VCF FM allows you to modulate the filter cutoff at audio frequencies to create all kinds of clanging cross modulation and bizarre alien splatters and sweeps. This effect works best with the resonance turned up into self oscillation but also produces good effects with lower resonance settings. The VCF FM waveform control allows you to select one of six sources for the FM modulation source. The options are square (PWM still has an effect), sawtooth, sub-1, sub-2, sub-2 pulse and noise. You can also use the external audio input as a source.
The VCF FM amount knob controls how much the filter cutoff is modulated by the source signal and the switch turns the effect on and off. The VCF FM is probably the most dramatic mod of the lot and while it can be somewhat unpredictable you can create sounds ranging from savagely aggressive grinding to unearthly ring modulation drones that wouldn’t sound out of place on the Forbidden Planet soundtrack.
PWM waveform source – Normally with the PWM set to LFO modulation you only have the option of using the triangle waveform as a modulation source. This rotary switch allows you to set the PWM modulation source to other waveforms independently of the main LFO setting. The options are Triangle, Square, Random, Noise, Sub-1 and Sub-2. The Sub waveforms are actually sourced from the VCO. Changing the setting of the sub octave switch will alter the sound with these sources.

VCF CV input – This jack socket on the top left of the case will accept an external voltage to control the filter cutoff. The suggested input is 0-5V but it can probably take a couple more volts if your Midi-CV converter can deliver them.
Audio Input – This is the jack to the right of the VCF CV input. It will accept an external audio input from any source and can be routed through the filter or used as another VCF FM source.

Audio input FM / VCF switch – This switch sets the destination of the audio input. With it set to VCF the audio input is treated as another oscillator and is run through the VCF and VCA in the same way. You will only hear the external audio if you press a key on the keyboard. Set to FM the audio input modulates the filter cutoff in the same way as the VCF FM sources except the external input can run at the same time as another FM source.
Audio Input Level – This knob controls the level of the audio input.

Filter Overdrive – This knob drives the VCO or external audio source into the filter stage causing the VCF to overdrive and distort. (The words Aggressive & Phat come to mind)

LFO rate extension switch – This is the three way switch located under the LFO rate slider. The right hand setting delivers the normal range of LFO speeds. The centre setting allows much slower speeds ranging right down to 25 second sweeps at the lowest setting. The left hand switch position allows outrageously fast LFO speed, well up into audio frequencies peaking at around 550Hz. Some evil effects can be gained by cranking up the filter mod or VCO mod sliders and switching the LFO to its highest speed.

LFO trigger input – This allows you to inject a normal +5v trigger signal to this socket which will restart to LFO waveform from its zero crossing point in a positive direction. The LFO will still run at the speed set by the slider but every time a trigger is received the waveform will restart. This runs independently of the clock and CV / Gate inputs allowing you to run a sequence via CV / Gate or the sequencer clocked externally and sync the start of the LFO sweep to a certain point instead of letting it run randomly. You can also restart the LFO anywhere you want in a sequence for special effects. One bonus feature of this mod is that it will also accept an external audio signal and retrigger the LFO at audio frequencies. Crank up the resonance, turn up the VCF mod slider, play a drum loop into the LFO trigger input and you can create sounds that will quite literally scare the shit out of you.

In addition to the mods offered on the circuitbenders website & listed above this 101 has an additional Seven x 1/8 jack sockets for extra modular connectivity and madness for....
VCF OUT
SQUARE WAVE OUT
SAW WAVE OUT
NOISE OUT
And 3 X SUB SWITCH OUT ( one socket for each sub octave )"