Hackers React to Korg Monotron Synth Schematic

Here’s a nice little counterpoint to recent events.

Yesterday, I posted on the blog about Korg releasing the schematic for their Monotron Synthesizer to the public. For those who don’t know, the Monotron is a small, inexpensive ($60) analog synth. It doesn’t have a “proper” keyboard, but rather uses a ribbon controller with a keyboard layout printed on top. It’s pure analog, with 1x VCO, VCF and LFO circuits. Users have found it to have it’s own unique sound, and to be very responsive to circuit bending.

Now, lest you think that this schematic was just a leak, I’d like to point out that it’s clearly labeled “FOR PUBLIC RELEASE”. This, coupled with the fact that the Monotron’s PCB has labels for various CV points, makes it pretty clear that Korg intended to enable, if not directly encourage, users to modify their Monotrons.

As news of the schematic has spread through the DIY synth community, I’ve enjoyed reading the responses of users. I think you will too.

From @bencc: “Awesome – more companies should do this.”

From @ezod: “If @KorgUSA weren’t already my favorite synth manufacturer, they are now!”

From @larrylegend: “The Monotron was already a super cool move by Korg. And now they just released the schematic to the public. I love it!”

From Luka at MuffWiggler: “i like it how korg are publishing the schematics and somewhat endorsing the modding of this machine.”

From jellyjim at SoundOnSound: “That’s a pretty unusual thing for a large corporation to do … interesting. Of the big three manufacturers (Korg, Roland and Yamaha) I think Korg are making all the most interesting moves just now.”

From Tadas at RetroThing: “That does it! I’m buying one. Love companies being positive about hacking their own products.” (emphasis mine)

And from James Grahame at RetroThing: “Korg’s move is in stark contrast to Microsoft’s dire warning that they’ll work with law enforcement officials to prevent people from tampering with their new Kinect controller.”

Thank you, James, for making the point so well. While Korg has garnered appreciation, good karma and, most likely, increased sales numbers from their efforts to open up their hardware, Microsoft has… well, y’know…

What do you think?

In the Forums: [OT] monotron hacking (p.s. nice work, phono!)

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  1. Time for Adafruit to get cracking with a midi kit for these 😉

  2. @Paul: A MIDI hack would be easily accomplished with either a Teensy or an Arduino UNO. Given that the “pitch” control is nothing more than a control voltage, you could simply strap an integrator onto a PWM output to produce the varying CV signal.

  3. @paul
    Yeah I was just thinking the same.
    Microchip released a nice midi demo in their usb stack right after I made my midi mixer and hacked together one. Ive worked with theirs on numerous music producing software and it is a great place to start. The low pin count USB development kit (comes with a pickit2) is a great place to start , with a PIC18f14k50, board , debug module, extra unpopulated board, its every thing you will need.

  4. You know, back when electronics were constructed from unreliable components like TUBES, it was pretty common to crack open a chassis and find a schematic glued to the inside cover. Or you could buy a service manual for a nominal price. After all, electronics were actually expensive enough to FIX if they broke…

  5. This is fantastic. I was already happy to see some of the stuff so plainly labeled on the circuit boards, but to release the schematics to the public just drives home the point that this little thing was made to be modded.

    I’ve got plans to do terrible things to my Monotron, and in that spirit, inspired by the release of the schematics, I’m going to see if I can assemble a gallery of DIY Monotron stuff in one central location, having just picked up the domain modotron.com — I put something similar together about 10 years ago for the Boss DR-110 at bit.ly/dr110 but I’m hoping that this turns out much better.

    Let the hacking commence! 🙂

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