Befaco I2

The Befaco I2 facilities the interaction between modular systems and external instruments. It contains an envelope follower circuit that affords precise control over signal amplitude. Additionally, the module produces a control signal that mirrors the amplitude of the input signal. Together, these features optimize the interaction between a modular synthesizer system and an array of peripheral instruments.

Since the module features both a 6.5mm jack and mini/banana jack, users can patch a variety of external signals into it. Each input is governed by a gain control, which dictates the overall amplitude of each envelope produced. There’s also a band-pass filter with dedicated cutoff, frequency, and bandwidth controls, which can be manipulated using the Freq and Width pots. After passing through the filter, the signal is pushed down to synth-level volume before it is routed to the module’s Audio Output.

As the signal is filtered, it feeds the module’s Response stage, which controls the envelope follower’s response velocity. A corresponding High/Medium/Low switch ensures that the envelope is always precisely matched to the processed signal. The extracted envelope is then routed to the Follo Out, where it can be routed to other areas of one’s modular synthesizer system.

I2 Features
  • External audio input interface
  • Preamp for gain staging external audio
  • Bandpass Filter for tone shaping
  • Envelope Follower for modulation controls dependent on input volume
  • Envelope Regenerator with attack and decay slew levels
  • Trigger Extractor provides a gate when the volume passes a decided threshold

Product Specs

Brand New (New)
I2 Instrument Interface

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Perfect Circuit
Joined Jul 2015
Burbank, CA, United States


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Perfect Circuit

Burbank, CA, United States
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Befaco I2 Instrument Interface
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