A Build with Variations variation: HiFiBerry Amp+


A variation on a variation!

I have a Hifiberry Amp+ in the hifi berry generic case and have decided to see if I can implement a fair bit of zynthian on it using bits that I have lying around…

Here is the topless hifiberry peaking out from under the desk . . .

Here is the top of the case with the four encoders mounted on stripboard

The cuts have been made in the stripboard and links has been added to take the centre track (0V) at the extreme ends to connect 0V to one of the SW encoder pins.

Here is the ribbon cable made up from an old disk drive cable

and here is it all kind of soldered together so I can test the directional sense of the encoders

and here is the whole thing with the obligatory pair of calipers for scale

Next issue testing the encoders,

I have used Vagnscott’s GPIO pin rewire because I have switched the framebuffer to hdmi output and do not have a 2 to 1 board.

Obviously this is just a desk rig at the moment but I will try to document the procedure from here to help as it progresses. No de-bounce capacitors & I would probably prefer to add the 2 10k resistors per de-bounce circuit to give a bit of protection to the rasp pi’s I/O pins.

p.s. I believe there are encoder test routines somewhere in the code base but I’m assuming I need to pull down more of the Git repository to get them . . .

One knob (LS) switches between engine & admin,
Nothing else is doing anything.


Maybe you should paste a screenshot of the wiring page in the webconf. Maybe we can compare one of your pictures with it.
For me it seems, that LS is the Back button right now


Don’t see anything when I point the browser at the ip address of the zynthian ( in my case)

webconf server not running ?

I’ve git cloned zynthian-webconf and run the shell script . . .
I get a login
but it 500’s on logging in which is presumably versioning …

I’m more of a mercurial user than Git.
I’ve downloaded the zynthian image which is dated December.

IT appears I have to pull the individual git directories in with git clone and presumably destroy my existing directories to build it all or is there some more effective way of getting to the current development branch?


Hi @wyleu!

From gorgona SD image, you should update using the “zynthian_update.sh” script twice.



Do you mean update_zynthian.sh … ? Cos that’s what I’ve just started . . . :scream:

Successfully !!! :grin:

I had reversed my i/0 connector :fearful:

So I’ll rebuild a new connector with a tasty bit of old disk drive ribbon cable . . .

The Two left hand knobs behave nicely, both rotate in the correct orientation so that’s that issue answered in the case of my particular rotary encoders, the right hand pair less so.
I suspect I need de-bounce capacitors . . . .

Nopr seems I don’t need de-bounce . . . hairline short on ls/sel board between OV line & sel switch . So Sel permanently pushed :slight_smile:

All rebuilt with much neater wiring loom…

Flip round the select encoder wires to get it the ‘right’ way for control surfaces ( it actually felt more intuitive the other way for menu’s on the left side of the screen initially…)

and it all works . . .

So, in conclusion.

He have a zynthian built into a standard hifiberry box with a hifiberry Amp+
It has no 5 pin DIN MIDI in but there isn’t really room for the socket.

Who needs a mixer?

I might have juggled the encoder wiring around to keep all the wiring on the same side as the encoders and avoid the wire 31 leap across but that would need some more mapping.

Now to start using the beast . . .


+if hw_version==“PROTOTYPE-VS1”:

  • zyncoder_pin_a=[25,26,4,0]
  • zyncoder_pin_b=[27,21,3,7]
  • zynswitch_pin=[23,11,2,22]
  • select_ctrl=3


I’ve made some holes in the case so you don’t need to open it up to connect and disconnect the speaker leads.

You can see why it would be nice if HiFiBerry silk screened the hole locations onto the box . . .

Might not be a good idea for a steel case of some sort because of the risk of shorting the speakers to ground, if raspberry pi steel cases are earthed … ?

Actually how is the zynthian case earthed…?

And are we absolutely sure Left is left & Right is right …? :astonished:


Hi @wyleu!

Zynthian alucase is connected to Jack and MIDI connector’s “ground”.



& left & right … ?


Jack connectors and RCA connectors (L & R) are the same. All the grounds are connected to the alu case :wink: