A feedback loop is something beautiful and dangerous. It is a delicate ecosystem that is always on the verge of collapse. Once we can keep it balanced, it becomes an excellent tool for making music.

Fumana is a non-resonant filterbank. However, we can create a feedback loop with a couple of extra modules and make it resonate: this gives us not one but 16 feedback points! We used the 321 as a sub-mixer and used its phase inversion switches to change the feedback color to taste.

The rest is all up to the control voltage. In this patch, we controlled FUMANA in many ways: through spectral transferring, through its macro controls, through its sliders. This is how we created a powerful (and dangerous!) feedback.


  • 1 FUMANA
  • 1 BRENSO
  • 1 321
  • 1 SAPÈL
  • 2 CGM Channel
  • 1 CGM Group
  • Reverb (Optional)


  1. Patch BRENSO’s Final output to an input of the 321.
  2. (Optional) Patch SAPÈL’s Fluctuating output to BRENSO’s Timbre Modulation Input and set the knob to taste.
  3. Patch FUMANA’s ODD and EVEN outputs to two separate channels (C) and pan them to taste.
  4. Patch their output to the other two 321 inputs.
  5. Patch the Sum output of the 321 to FUMANA’s Main input.
    (The 321 now handles the feedback loop.)
  6. Combine the FUMANA’s faders, the CGM knobs and the 321 knobs to achieve the desired feedback.
    (You can also use the phase switch on the 321 to change its tone.)
  7. Patch SAPÈL’s Random clock output to FUMANA’s Mod In to excite the bands.
  8. Patch SAPÈL’s S&H output to FUMANA’s Position CV input.
  9. Patch SAPÈL’s Clock output to one of FALISTRI’s trig/gate inputs to fire an envelope.
  10. Patch the envelope’s unipolar output to FUMANA’s Tilt CV input and andjust its level to taste.
  11. (Optional) add some reverb.