Benjolin

Screen Shot 2021-01-25 at 8.43.26 AM

Benjolin Module

This is a module based on Rob Hordijk’s Benjolin. It features two oscillators a “rungler” circuit and a multi-output resonant state variable filter. The rungler circuit is an 8 step shift register that takes its data from oscillator A and its clock from oscillator B. This is fed into a DAC and the DAC’s output is fed back via the Rungler knobs to the two oscillators and the filter. The modulation knobs provide cross modulation between the two oscillators and modulation for the filter from oscillator B. The Loop input switches the shift register to recirculate mode and the loop control provides an offset. A more complete description can be found here: Epoch Modular | Analogue Haven

Note that feedback delay nodes are used in the feedback loops to minimize CPU load. More accurate results can be obtained by replacing them with unit delays


I/O

Input Signal Range Notes
Loop modulation 0-1 When the loop toggle is on if the sum of the loop knob and the mod input is greater than 0.7 the shift register will loop.

Output Signal Range Notes
Pul A 0-1 Pulse output for oscillator A
Tri A 0-1 Triangle output for oscillator A
Pul B 0-1 Pulse output for oscillator B
Tri B 0-1 Triangle output for oscillator B
PWM 0-1 Pulse width modulation output for oscillator A
Rung 0-1 Rungler output
XOR 0-1 Exclusive OR (XOR) between oscillator B and the rungler
HP 0-1 Highpass filter output
BP 0-1 Bandpass filter output
LP 0-1 Lowpass filter output

Controls

see description

Displays

none


Version History

Revision File Date Notes
3.2 Benjolin V3.2.audulus (269.9 KB) 01/25/2021 reduced SVF max frequency to prevent crash

Demos

Revision File Date Notes
2 Likes

This Is awesome :+1: thanks for sharing!
(And thank you @robertsyrett for bringing this up. Is this something that was already shared in the old forum?)

Oh one thing:
Benjolin V3.1 (white wires of doom).audulus (126.3 KB)
I managed to break it :smiley:
(let this patch run around six seconds and you’ll get white wires)

1 Like

Ohhh the 3.1 version, time to upgrade!

The SVF design I used tends to be a bit unstable at high frequencies. I though I had it adjusted so it wouldn’t run away but I guess not. The 3.2 version reduces the max frequency somewhat to prevent the white wires (I hope). Real hardware just goes into saturation but that’s difficult to model.

3 Likes