My build progress

Cheers! Still got bugs, but just nice to see it flashing and possibly functioning. I still need to build a teensy4 wav trigger thing n see whats left to fix =)

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Super tidy! Nice work!

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As promised to @Jos and @THOGRE here’s the code my @HAGIWO inspired LFO/VCO is running. It’s not super clean (I’m not a huge fan of C++ and I just concentrated on making it work) but it should make sense.

Things to note:

  • I use PlatformIO instead of the Arduino IDE, so the code itself is in the /src directory
  • I rewrote the code for my own needs, so there’s a few libraries required - they’re listed in the platformio.ini file. U8g2 runs the OLED, SimpleKalmanFilter smooths the pot and Switch makes handling the push buttons a bit simpler. They should all be available in the Arduino IDE’s library browser. There’s also a library in the /lib directory (it’s not available in the PlatformIO library browser), which simplifies talking to the AD9833.
  • My hardware is a bit different - the CV input is on a separate pin and the summing is done in software, plus there’s the three buttons. (Also, I’m using an LM358 opamp because I have a load knocking around from years ago :grinning:)

I still need to add some finesse to how the knob is used with the CV input in 1V/Oct mode but that’s only really there for an added bonus, its day-to-day usage is just an LFO. Anyway - there you go, hopefully there’s something in there that can help


Today i put my triple LFO in the case

It’s my implementation of the simple LFO by Niklas Rönnberg

My verified stripboard layout here (under the Dialphone :wink: )


That is sick !!! LOVE IT !!

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@irregularshed: Great, thx!

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Nice LFO there.
I’m interested to know does the frequency change if you change the shape from saw to triangle? It looks like the wipers of the shape/freq pots area tied together - which if it works is a nice trick. I jumped through hoops to get saw/tri shaping while keeping the rate constant on my LFO, and didn’t think to do it this way.


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Dud , did you use 50k trim pots on your version of triple lfo , like the schematic ?

another pcb I had done just needed to make face plate and wire up .
BMC 031 Quad Trapezoidal LFO . kind of a different thing should be interesting .


I recommend LED resistors from 1kohm to 47kohm.
In my case, I used 33kohm because using high brightness LED.

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(if I understood your question correctly :slight_smile: )
the frequency (or Rate) of the LFO don’t change with shape pot use.

yes (maybe 47k because i don’t have 50K)

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thanks Dud , it looks like an interesting project , not like I don’t have a million others to finish .


a pair of Barton Musical Circuits wave shapers , BMC 033


Nice, I did one also on stripboard and it’s a really interesting module.


Here’s mine


Got Duber workin :slight_smile:
a dual resonant state variable filter.

Sweep tests

LabRolz Ping test.

ROOLZR click pop ping :smiley:
Circuit it is based on

^ an old ciat-lonbarde Duber - before he got famous :stuck_out_tongue:


Today, CV Joystick/Wheel in the case !

A mix with 2 schematics (joystick and wheel)

On one joystick i keep the spring inside to use more like a wheel.

All axes have Offset and Range pot
Wheel have a switch fore 1 oct or 5 oct (positive or negative)

it was long for me to calibrate it, but that’s it, really fun :slight_smile:

A video which after having listened to it again with a little atmosphere of K2000 :racing_car: :wink:

Schematics and my verified stripboard here


I’d be curious to know what your experiences are when applying it on different input wave shapes.

With a wet/dry pot, an AC and a DC out, here is mine: