Success Cases


It’s really a nice Zynthian “Case” :wink: Congratulations!!


KUDOS!! You beat me to it! Beautifully executed design! I’ve been working on this exact thing for the last week. Mines a-lot different however.


@hit3c, I’m looking forward to see the results :wink:


Three zynthian minors arguing over an HDMI connector . . .

One hifi berry Amp one Audio Injector & and an Audio Injector zero . . .


What a happy zamily!! :wink:

split this topic #95

A post was merged into an existing topic: Distributing MIDI over IP with zynthian


whaouhhh ! Congratulations


Hi guys!

I made my Zynthian in a 19 "rack cabinet.

The idea is to use mainly with guitar, so I chose to use the audio injector.

I did some extra circuits too:

  • A simple preamp for each channel, with a peak indicator light

  • A controller made with arduino, with 12 potentiometers

  • For the encoders I made a simplified version of the plada with the MPC23017, the connection of the wires is done with soldering in the pins GPIO

I have not yet made the PCB for the MIDI connectors because I don’t need it now :yum:

Here some pictures:



Power Supply


Arduino Controller

MCP23017 Pcb

Regards, Rod


That’s absolute fantastic @rod_amaral!!!

Do you have more information about the used pre-amps (e.g. where to buy or the circuit diagram)?

Regards, Holger


Woaooooo Rod!! Your Zynthian is a f***g killer-monster!! Congratulations!!

I suposse you will be using a lot the MIDI learning subsystem with your extra “Arduino MIDI Controller”. Keep me informed of the problems you find, please …



Wow! IMHO this is the best case so far!. :slight_smile:


Thank’s Guys!


It is a simple preamplifier, using an TL072 and a BC548 forthe peak indicator.

I put a trimpot in the circuit to control the total gain of the circuit, but i believe that it is still possible to improve this schematic.

I made the drawings using Eagle (Autodesk), you can find the files here.

I’m also using a separate power supply for the audio pcbs. In the first tests, when i used the same source as raspberry, had a lot of noise in the audio signal.

I’m still planning to mount two buffers for the outputs. One with P10 plugs output, with gnd line isolation and another balanced with audio transformers and a ground / lift switch.


About using the MODUI with the MIDI controller, i only noticed a small problem when I use the select button to browse the existing plugins in the MODUI pedalboard. Plugins are switched on when the selection button is used to navigate.

Regards, Rod


Interesting . . . .

I wonder if two of the DC Converters in this Power Supply for Zynthian would provide the same degree of cross-talk isolation?

How did you divert the power into the Audio Injector?


What about a wiki entry with links to the components?


hi @wyleu

The raspberry and Audioinjector are being powered by the same supply.

The second power supply is now being used only for the preamplifiers. In the future it will also be used for output buffers.


Presumably one could cut the track from pin 1 (5V) on the 40 way and feed the on-board AMS1117 from your separate supply or a DC to DC converter as per the Power Supply.

Anyone Put a scope across the +5V on a Pi/Audio Injector?
Kind of . . . .


Hi, please tell me, where did you get the front panel from? I am not able to find normal price for cutting a rectangle for the screen… :frowning:


Hi @martin_SK

that panel was made with laser cutting.


Hi Guys!

Some sound samples:


thanks, and is it alumium or steel?