Zynthian Box with Audio-input (Audioinjector soundcard)

we need numbers that compare AudioInjector with AudioInjector Zero.
Those issues were the reason, I bought the Zero.

Just literally finished putting an audio injector zero into a berry case . .

The zero gives you a lot more flexibility, if you use the supplied connector mountings.

Ain’t soldering the edge connector a right old pain?

There are several different design of 2*20 pin long pinned headers and a few of them have quite high bodies which forces the audio injector board higher.
I’d almost prefer audio injector to supply a pre-soldered header but I can understand their point.

The mounting of their pre-supplied RCA connectors requires a screw of indeterminate size. I ended up drilling out the ptfe to suit what I had.

I ended up cutting off the ends of the connector boards that would contain the volume control so they take up less panel space, but I’m sure the Pot is a must have to some. Either way just cutting the board allows pot less operation with no problems.

Of course if Hifiberry produced an in/out card or better still an in/amp+ then I’d skitter back.

That’s customer loyalty for you.

BTW something that bothers me ALOT with the audioibjector is sound quality. I can hear every screen refresh in the sound. I think that decent electric shielding is really critical for Zynthian to become a good audio tool.

It depends a lot of your setup. A good grounding with a metalic case can help: display, encoders, Jack connectors, etc.

In the past i had this problem with several Zynthians, with Hifiberry and also AudioInjector soundcards. I don’t think the sound card is the problem.

My recent builds works perfectly quiet, without noises when the GUI refreshes. I’m not sure of “why”, but i suspect that is a combination of factors:

  • First, adding the 10nF debouncing capacitors to the controllers PCBs reduced the number of commutations of several GPIO ports when rotating the encoders. You have these :wink:

  • The new All-In-One circuit reduces the number of GPIO ports changing its state. All the encoder & switches information flows by the I2C bus. I think this may reduce the noise close to the soundcard. You also have this :wink:

  • I suspect that the OZZMaker PiScreen is better shielded in the PCB bottom, reducing the noise inside the case. This is specially related with GUI refresh. Are you using the clonic PiTFT 2’8" or a generic HDMI display?

  • Of course, the aluminum case, bond to connectors “rings” and display PCB holes. Curiously, i didn’t perceive any difference when the metallic separators used to attach the “main computing block” (RBPi + Soundcard) where replaced with plastic ones, isolating these mounting holes. Your ASB/PLA case doesn’t help with this, although you could add some “extra grounding”. I’m not an expert, so perhaps somebody more experienced could give you some tips.


I can hear any CPU process happening. Mouse movement, stuff like that. It seems like shielding between the Pi and the sound card is where the sound comes from.

  • I also made a cable that connect to electrical ground the USB ground+case. that also helped with buzzing.
  • thinking on how to improve:
    • the aluminum case might help, I have no way to test that here. I wonder if I should replicate the build you have there. I need to figure out how to make the aluminum case with the audioinjector, and I think a better screen

    • I am pretty sure the sound quality on the audioinjector needs improvement, it might be also the signal in needs some clearing somehow.

Definetely the AudioInjector sound is not the best :wink:

PiSound? The go for 99EUR which seems like a lot for an experiment, or in general really.
Can’t seem to find a solution here.

Has anyone tried using screened cables from the audio injector board?If I find some time I’ll try getting some audacity recordings of the beehiving I get on audio injectors and see if I can quantify it.

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Hi I’m new here, half way through a Zynthian build.

Sure you are not getting “FE” (Active Sense) looping?,
much Roland gear uses Active Sensing to let the controller know it is still midi connected if the Buss is quiet.

No, it was a bug that is fixed by now

We had problems with AS but now it should be working OK. AFAIK, the only MIDI commands that should create problems are “big” SysEx sequences.

Anyway, a bug could be hidden, but i would need a way to reproduce the error…


I don’t know if this is the best thread to ask but, Is it usually cheaper to 3D Print a case (like with Shapeways) than to get a lasercut version made? I found the lasercut file for the AudioInjector version but I guess I’d have to modify the cutout for a 3.5" screen? Also add MIDI-Thru. There is no finished design for this in 3D Print or Lasercut, right? Best bet is to learn Blender basics?

My AudioInjector boards just arrived and I want to build a second Zynthian with a 3.5" screen and a MIDI Thru. Modifying the laser files to accommodate is now on my short list. I’m still kind of busy, but I will be posting my updated case onto github soon (I hope). I’ll also try to post some photos of the case when it’s done.


Well, here’s my first prototype laser-cut AudioInjector Zynthian box. I rotated the Pi and card 90° to allow direct access to all the I/Os. Unfortunately, the All-in-One board is just a bit too long to fit nicely in the standard sized case with a rotated brain. I’ve got a few ideas though, like mounting it at 45° and also cutting it into 2 pieces. Perhaps I’ll give both a go. Notice the 3 holes for MIDI IN, THRU and OUT. I’ll also add some holes for the LEDs. Love to have your comments and suggestions.


:grinning::grinning::grinning: I don’t have any suggestions right now but this is very exciting! I love how compact it’s looking! Maybe the all-in-one could be mounted higher with custom wiring and wood as standoffs? Then I imagine it would be half hovering over the audioInjector, and I also don’t know it that’s good for heat etc? I have no experience with any Zynthian case in person. Ok I guess had I some ideas :slight_smile: Oh! One thing I can’t see is if there’s access on the bottom to change out the SD card. I realized I couldn’t get to it when I was just trying to mount mine to a board, so I had to raise the RPi up about an inch with some plastic so I could barely access the card.

I’m always dreaming up weird case designs in my head, like a very short in height rack-style Zynthian with the 4 encoders and screen facing 90 degrees forwards. (like that amazing metal one someone made but a lot smaller and thinner.)

Or spreading everything out horizontally, also very short height, with extra encoders. It would take up more desk space though.

Do You Mean …Success Cases - #62 by Schpion


Not easy to beat!! @Schpion put the level really high!! :star_struck:

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I can’t seem to in-bed an image from that thread here. . … .

Easy, my friend. From your browser’s left-click menu, copy “Image’s URL” and after paste like that:




Besides that, @rockwater meant the recent metal rack, but as U1.