Synthrotek ROBOTO - Eurorack Modular Build

Synthrotek Roboto DIY Kit
Roboto Eurorack DIY Kit by Synthrotek

As 2019 came winding down, the gang out at Synthrotek sent us over the Roboto Eurorack DIY kit and low and behold, we were onto another build. The Synthrotek Roboto was originally released in 2017, but has quickly become a staple in a lot of musicians racks due to its versatility and uniqueness. 

From the first module in our rack, we have always had our eyes on the Synthrotek Roboto. We were excited to finally take this one and see what it could do. Roboto is known as a vocoder, pitch shifter, speak-n-spell effect processor, vibrato provider, an 8-bit modulator or plain and simple…  a bit crusher.

Now, let’s get on with the build.

Time Lapse and Build Notes

Play Video

The DIY kit comprises of a panel and 2 PCBs. One PCB is the control board and the other is the logic board. These two boards will be connected via standoffs and a vertical spacer. Synthrotek does a great job with their assembly instructions (provided via their website) and BOM, so it is easy to jump right into the build. Start out by populating the diodes, standoffs and IC sockets.

Resistors in this kit are vertical resistors and you can solder from the top down to make it easier to flip the board when reaching the components from the bottom. There is one resistor on the control board that mounts next to the LEDs, so take note of this one labeled R1 via the BOM. 

After getting the build completed, we decided to jump right into patching the Roboto Eurorack DIY Kit. We were impressed by the tone and were able to adjust the incoming signal with the IN LVL pot. The other pots are for the rate/clock speed, pitch and lastly MIX. The MIX pot controls whether the output is that of the input signal or the processed signal. 

Roboto flyer
The sound of science!

Controls and Specifications


  • Can be in either Robot mode or Pitch mode, but not both. Handy LEDs tell you which mode you’re in. The ROBOT button toggles between the two.Vibrato toggles on and off. Works in either Robot mode or Pitch mode.
  • Robot and Vibrato CV inputs activate those modes (and deactivates in the case of vibrato) upon receiving a gate pulse. Gate pulses in these inputs are just like pushing their corresponding buttons. Expected transition is from 0V to +5V (and back to 0V), but it will handle any voltage within the power supply range without damaging the module. Transition between what is considered “off” and “on” is at approximately 2.3V.
  • Rate pot/input control the clock speed in the chip. A CV input of 0-5V will mimic the range of the pot, but voltages outside of this range will push the rate setting further.
  • The CV input is mixed with the voltage coming from the pot.
  • The pitch pot is used to pitch the audio up or down when in pitch mode. It has 7 zones/pitches; 12:00 is normal pitch, and there are 3 steps up and 3 steps down from there.
  • 0-5V fed into the Pitch jack mimic the full travel of the pot (0V is lowest, 5V is highest, normal is ~2.5V). Voltages outside this range are tolerated but won’t provide any added functionality.
  • The pitch pot is disabled when a plug is inserted into the CV jack.
    Roboto is fun at parties.
  • IN LVL adjusts the level of the incoming signal.


  • CCW=input signal only
  • CW=processed signal only
  • Robot LED indicator

Power Draw:

  • +12v @ 65mA
  • -12v @ 15mA
  • +5v @ 0mA


  • Depth: 34.5mm (1.36in)
  • Width: 6HP
  • Height: 3U

Purchasing Information

Panel and PCB Combo

  • Black Panel with Cylon decal
  • Dual green PCBs
  • List Price: $35.00 USD
  • Click on the image to be redirected to the Synthrotek Store Page

Roboto Eurorack DIY kit

  • Includes all components, PCB and Panel for assembly
  • List Price: $99.99 USD
  • Click on image to be redirected to the Synthrotek Store Page

Assembled ROBOTO Module

  • Fully assembled and calibrated 
  • List Price: $149.99 USD
  • Click on image to be redirected to the Synthrotek Store Page

Synthrotek Roboto Eurorack Module ... Patching

During our first patching experiment, we were able to patch the Roboto with the LimaFlo MotoMouth, alongside the EVENT and Tone Modules from Rat King Modular. We decided not to provide an audio demo of the module because there are quite a few out there. Our time-lapse video above serves as the only build video we have found on the internet, so it was important that we shared our experience with this fun little module. 

If you have questions about the build process or suggestions/feedback about this article, feel free to let us know by contacting us.  We look forward to hearing from you!

Until the next build … 

~ f i N

The Long view of Roboto