Benjolin | The Big Knob Spider DIY electronics | SYNTH

For a perfectly unpredictable noise synth, the Benjolin is actually not hard to make. The PCB design for DIY etching and bill of materials was kindly provided by Peter Edwards Casper Electronics. With the last update of his page the schematics, PCB design, parts layout and bill of materials migrated to Electro-Music Forum. Peter has the official approval for sharing this beautiful piece by Benjolin’s creator Rob Hordijk. We etched the board at Ljudmila and it was a lot messier than the instructions for etching PCB in-house.

Here is the intermediate result. I needed some time to figure out the best casing for the instrument. I do not really like crude aesthetics and square minded assembling of electronics in ugly boxes. At first, it seemed to me there is so much more to be expressed in the interfaces that we produce. I strongly believe the interfaces (like the way modular synths are assembled) are not the most logical way to build them but just a cultural consensus. To change the hegemonic male-dominated culture, one needs to think about different interfaces… braking a wire or a knob in the meantime…

Here is a picture of the first attempt. My wish was to combine beauty, cultural disobedience and big knobs in the same casing. Mental note: potentiometers on Benjolin are highly sensitive so it makes sense to use really huge knobs.

Benjolin #1
Benjolin #2

There were a few mind boggling twists in the making, like getting a “not too expensive” Yamaha YM2164 chip. Getting an original would cost around 25€, so getting a clone at Small Bear was much more tempting and it works just fine. Another saga that took me some time to figure out was the power supply… this was my first instrument that required a +/-15V power supply that is generally used for modular synths. Down below is my brick which powers two benjolins and Wolfgang Spahn’s [dernulleffekt] PB808 Kick Drum paper-pcb.

PCB etching
808 Kick Drum paper-bit

Plans for new casing with double benjolin and modular extensions inspired by Hallik Engineering Ambika case-design.