Vostok Instruments - Sigma

Sigma is a four-channel gate processor for turning a small amount of timing information into a much larger rhythmic network. Feed it clocks, triggers or gates, adjust the length of each signal, and Sigma starts producing new related patterns from them. With four inputs and up to 23 simultaneous outputs, a fairly simple sequence can quickly spread across drums, envelopes, switches or modulation elsewhere in the system.

The nice thing is that all of this happens through very basic modular interactions: turn the four length controls, patch a different logic output, and the rhythm changes underneath your hands. Because the logic section is constantly comparing the processed signals against one another, altering the length of just one gate can change several derived patterns at once. You can keep the results close to the original pulse stream or pull out denser, sparser and more syncopated variations without having to rewrite the source sequence itself.

Sigma combines digital gate-length processing with an analog logic section, but the point is less the hybrid architecture itself than what it lets you do with very little fuss. One clock or trigger pattern can become the timing backbone for a much larger patch, while the relationship between those events stays easy to follow and easy to disturb. For rhythm-heavy systems, it gives you a very direct way to make existing sequences work harder without adding another sequencer or another layer of programming.

Features:

• Four-channel gate and trigger processor
• Generates up to 23 simultaneous gate outputs from four inputs
• Independent gate-length processing for each channel
• Gate-length range from 1 ms to 10 seconds
• Infinite gate-length mode
• CV control over gate length on all four channels
• Main processed output for each channel
• Dedicated NOT output for each channel
• NOT outputs can also function as gate delays
• Analog logic section for channel pairs 1–2, 2–3 and 3–4
• AND, NAND, OR, NOR and XOR outputs for each channel pair
• Hybrid architecture with digital gate-length processing and analog logic
• 5 V gate outputs