£199.00 (£165.83 ex VAT)

Complex Random Voltage Generator. An 8HP redesign of the Erica Synths Swamp module – which was originally inspired by the famous Wiard Wogglebug module.

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The After Later Audio Bog is an 8HP redesign of the Erica Synths Swamp module – which was originally inspired by the famous Wiard Wogglebug module. The ALA Bog has moved the “Smooth” range switch to the front panel and added an input for the S&H circuit (commonly called the “Heart” input).

The original Wogglebug was a random voltage generator, originally designed by Grant Richter of Wiard Synthesizers. It is a development of the “smooth” and “stepped” fluctuating random voltage sources pioneered by Don Buchla within the Model 265 “Source of Uncertainty.”

On BOG, the Smooth and Bog outputs have their own independent Range controls. The Cluster control affects both of these outputs simultaneously – along with the Stepped CV output – controlling how much random changes occurs. These controls are all somewhat “interactive”, and the BOG signal is affected by the Bog Range, Smooth Range AND Cluster control. All Wogglebugs (and their derivatives) have been designed to be “steered” in a general direction, rather than controlled in a laboratory-level fashion. Some changes may not be apparent immediately, due to the interaction between the various controls.

The Time knob controls the frequency of the random changes on the Smooth output. The Rate control sets the internal clock speed, which is the overall “master” tempo for the BOG. You can also sync to an external clock if desired. You can also modulate the speed of the internal clock via the Rate CV input.

If you output the Stepped CV into gate inputs of other modules you can usually generate a pseudo-random gate, as most gate inputs detect voltages above a certain threshold….so some steps will trigger the connected module, whilst others will fall below the threshold and be ignored. This can be a great way to generate random timing events that are related to the carnage taking place within the BOG!

The BOG also features three random audio-rate signals – Tone, Bog and Ring. The waveform can be switched between Square & Saw on both the Tone and Bog outputs. The Ring output is the result of the Tone & Bog signals being Ringmodulated. You can also choose to input an external signal into the Ring Modulator (instead of the internal Tone waveform). These audio outputs can work really well (especially the Ring output) when fed into Lowpass Gates and used as the basis for percussive sounds. Using the Clock output will synchronise the BOG’s voltage/pitch changes to your external gate sequencers, should you want to use complex/ erratic rhythms generated by other modules.

Experimentation is the key!

BOG Features:

  • Newly added S&H/Heart input
  • Smooth range switch now on the front panel
  • Three random audio frequency outputs
  • External audio input routed to ring modulator
  • Three random CV outputs
  • Clock input and output to sync the module to your modular system
  • CV control over internal clock for even more extreme randomness
  • Skiff-friendly design and only 8HP

The Erica Synths Swamp Manual is a great resource for getting started with BOG!

Based on open source design by Erica Synths under Creative Commons (CC-BY-SA) license.

Width: 8hp 
Max Depth: 24mm 
Power: 60mA @ +12V / 39mA @ -12V

This Erica Synths SWAMP video gives you a good overview of BOG’s features
(note: the “Swamp” signal is called “Bog” on BOG)