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Building a Zynthian

I stumbled upon the Zynthian open source synthesizer platform project some months ago and found myself visiting the site even more often than hacker news. Eventually, I ended up buying a Zynthian build kit and did not suffer buyer's remorse since I was looking for a new hobby project anyways which would not be at least entirely coding.

Zynthian is in a nutshell, an open source synthesizer platform. It comes bundled with a set of open source Linux synths, effects, and other audio software. The kit I ordered contains a Raspberry Pi, an RPI sound-card, touchscreen, some audio ports, and encoders. All this is connected via a purpose-built printed circuit board.

I was a bit rusty on my soldering skills so while waiting for the parts to arrive, I practiced a bit on some old hardware salvaged from my parent's farm. I just merely desoldered and soldered components as a way to practice

The actual building was relatively easy, mostly because of the fantastic instructions provided by the Zynthian wiki. I took my time and tried to build it as well as I could.

One of the encoders assembled

The finished PCB which connects everything
The first power on was an exciting moment. As nothing works with the first try, I did not attach all the parts to the enclosure. And as predicted, the first boot was a failure, the touchscreen was not working quite right.


Something wrong with the screen
The first suspect was insufficient or too low a quality power supply. So I tried with the official RPI supply, but it did not help. Then I loaned a Raspberry Pi from work, but still, the screen was all weird. I temporarily used my PC display to verify that everything else was working and indeed the device was perfectly usable. Next up on the list of possibly faulty components was the ribbon cable connecting the display. I replaced that with plain jumper wires but no luck. I concluded that the screen would have to be broken.

I posted about this issue on the Zynthian forums, and within a few hours, a new display was on its way!

While waiting for the screen, I started digging into the software side of things. The Zynthian software is as mentioned open source along with the hardware specifications and proved quite useful when learning how to use the thing. For example, the UI is written in python, and I could read there how the encoders, for example, control the UI navigation. The updating is also pretty nice, there is a script which downloads the latest master from GitHub, compiles and voila, a new version is up and running. Using an own fork of the official software is possible by simply altering the update script repo paths.

I have a couple of ideas on how to make the software work a bit better with the touchscreen, let's see if my thoughts will actualize at some point.

Zynthian setup with a midi keyboard and a PO sequencer




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