Building a custom Zynthian

This is the documentation of my first custom zynthian build. It is work in progress and will be expanded over time. I really got much help of others in the forum, this thread can also be seen as part of the documentation.

1 The plan

After initially only wanting to get into this project by connecting a bare PI to a HDMI display and an external USB audio interface I considered building a custom Zynthian with a nice case and at least four encoders and stereo input and output connectors. You can read below how that succeeded.

2 Parts used

Parts used in this build are the following (will be specified in steps):

• Raspberry PI5 with official active cooler
• HifiBerry DAC2 ADC Pro
• MCP23017 GPIO Extender
• 8 inch Waveshare HDMI Touch Display
• 4 rotary encoders
• ceramic capacitors of 10 and 47 nF
• ...

3 Planning

I'll act here like I had the final device already in mind when I started out. The truth is, that the design changed over the process of building oftentimes, but I don't want to bore anybody with that.

3.3 Cooling

The PI has the official active cooler mounted. In the beginning when only the PI was mounted on the display in fresh air, it got ridiculously low CPU temperature values. Things to consider:

• Many people here swear by passive cooling connected to a metal case, because cooling works good and it has no noise. I couldn't do that, because a wooden case can't distribute heat.
• The PI living in a case forces you to think about air ventilation within the case.
• A HAT mounted onto the PI will raise heat considerably, because the air from the cooler cannot move so well. I had to raise the audio hat with a 9mm 40 pin header to not conflict with the cooler anyway.

With all these things in mind: My Zynthian never exceeds 60°C CPU temperature.

7 Further plans

I already have some parts lying around if ever I find time to add these to the build and also find the courage to disassemble a working device. These include:

• More MCP23017 expanders for physical buttons
• 20 Capacitive buttons to mount under the thin wooden top to act like the 20 V5 buttons.
• A TOF sensor for altering parameters with magic air gestures
• Some plywood to build a more sturdy case
• Probably moving the audio HAT off the PI with a 40-pin GPIO extention cable for better air ventilation