Back in May 2025 my wife and I had a really enjoyable first visit to This Museum is Not Obsolete. We met Midge , who was a super host. and I donated a Bruel & Kjaer accelerometer unit with transducer. I keep wondering what the genius in chief will do with it…..
At the end of the visit I bought a Fart Box PCB. Great souvenir! I normally build digital amateur TV equipment so I enjoyed the build of the synth. An optical centre punch helped with getting all those hole centres off the paper drilling template spot on. I use a pillar drill in my workshop. I think the FB works well but the real issue is I have no idea about electronic music!
Matthew North Music has the nearest thing to a helpful instruction video on the construction of the FB. He was using a midi controller to get it going. I was able to buy an Arteria Keystep for £40 locally. With the box Cv and gate outputs from the Keystep, it started making noises and sometime pleasant sounds too.
It doesn’t stop once it’s under way. Being a bear of small brain who has read the Keystep manual [which assumes familiarity with electronic music], I haven’t a clue how one is supposed to control the synth from the controller keyboard. Or was I supposed to drive it with e.g. a drum machine like a beatstep pro?
Please may I have some advice on what I am and am not doing? An instruction video on the project and getting it commissioned up and running would be a splendid thing on the Museum channel. It would support those who’ve bought a souvenir board like me but are not synthesisor trained.
This one is intended for a Christmas present for my son. He’s a pianist and bass player. I made him a cigar box guitar a couple of Christmases ago
You need to connect the gate out of the keystep to the gate in of the fartbox, set the envelope switch to “gate”, and then connect the pitch out of the keystep to the CV in of the fartbox to get it going. This way the sound will come up only when you press a key on the keystep and (after some calibration), the sounds will also track the pitch of the keyboard as well.
Yes to that, but do not expect any sort of calibrated key tracking. It’s pretty wildly inaccurate in my experience (And also isnt really what this synth wants to be anyway)
I do show that Pitch is connected to Oscillator 1 and gate is connected to gate. The trigger and gate switch gets switched to gate position and continuous sound emerges. Nothing I can devise makes the keyboard interrupt or play the synth. What else shall I try please?
This is not the synth that I would have bought a keyboard to control. It was absolutely a reasonable thing for you to assume given the CV/Gate inputs, but that’s just sort of not what this synth is really meant for. Notice it’s a “CV” input and not a “1v/Oct” input.
It’s inherently wild and uncontrollable … and in my opinion those characteristics should be embraced.
Is your “fart button” working?(didn’t think i’d be using that phrase today). The gates you send should accomplish the same thing that your button does … this too will require some tweaking.
I’ll typically hook my korg sq-1 up to it and send sequences of gates/voltages at it, but with no expectation that it will be in any real musical key. As far as calibration is concerned - I found the trimpots inside to be gentle “suggestions” at best
So my suggestion would be to use your keystep to generate sequences for it. This will get you some rhythmic loops to play with and tweak, but your dreams of composing a fartbox-version of Moonlight Sonata are probably dashed.
I don’t think that the problem he has is about tracking 1V/octave. It seems that the CV cannot track at all. The gate is not working either if he’s getting the same continuous tone. I would say that this needs proper troubleshooting.
there is a thread dedicated to fart box builds, it even has a annoteted PCB that groups components together according to their functionality on the board. maybe it helps debugging your instance
from my own XP fart boxes are hard to debug and tame. i rarely encounter a setting that is playable (~v/oct) and was surprised multiple times by what sounds are in there while fiddling with the knobs
My CV tracks … but even when it does I have to sort of get things into a sweet spot. Same with my gate. Until I adjust my knobs until the button does something … the gate certainly won’t either.
Ron and I were studying the schematic at amateur radio society this week. He’s a retired electronics engineer and was cursing the disjointed nature of the diagram. There’s a lot of fault finding to do and looking at signals on the scope
I shall learn to use the keystep with some audio workstation software as a first baby step.
I have a shorting link in parallel with the fart button. It’s set to continuous operation as a result at present. Rather like the Matthew North Music’s example. Matthew replied to my comments on his video that a Behringer Swing midi controller would do for connection to the FB.
How did you bypass the button? If you look at the schematic the gate input seems to go through an attack/release stage and then through the button itself. That’s why I suggested getting the button working first - as the gate seemingly just presses the button
