Orac 2.0 for the Raspberry PI


not currently…

basically this requires me to modulate the DC on a AC signal, but whilst I’ve sound descriptions of the hardware required - I’ve not seen specifics of how to modulate the AC modulation - and I don’t have the hardware to test it out.

if someone can tell me the specifics (e.g. frequency of AC carrier wave)



The circuit is a Envelope detector…

The AM signal is processed and transformed to a rudimental DC (positive) signal.
You might need a oscilloscope to check if this trick is working.

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Hi everyone, does anybody knows how to

  1. Send midithru message on midiout
  2. Add line in sound to the orac mix.


go to the router (module s1)

  1. midi ‘thru’ (fo/r midi notes)
    on a particular chain, check that midi in is ON, and the midi in and out channel is set to non-zero
    if the chain just has ‘empty’ modules then midi notes will flow thru, if you have a synth in the chain, then you will need to set note-thru =on , on the synth module in the router (e.g. a1)
    it wont sent thru other midi cc etc… if you want to do that id suggest setting this up with alsa as it be more efficient… (why go alsa -> pd (orac) -> alsa)

  2. audio in
    in the router go to the relevant chain, and turn up the input gain
    then audio will flow thru the chain.
    (there is an audio thru, again for synths modules that usually wont pass the audio thru)



I want to send clock (start, etc)from a midi out controler to a drumbox via midi out of the pisound and play the sound of the drumbox mixed with the orac without lost the three midi chanel. The drum box as another midi chanel, is that possible with your tips?



audio, sure do as i said for 2.

midi, i would send directly via alsa… as it makes no sense (=introduces latency) to do the
routing in pd/orac

look at the aconnect command…

btw: if your using PatchboxOS, then i thought this would happen automatically,
as amidiauto by default connects everything to everything else?!



The audio in work fine thanks. But i tryed every configuration possible (master midi in, slave midi out. Master usb. Master and slave usb…) and the clock doesnt pass thru. I use pisound with patchbox os btw :wink:



Can you tell me more about the aconnect please?



It connects by default only MIDI software with hardware MIDI ports. In case you want hardware to be connected to hardware, you’ll have to set up the rule in /etc/amidiauto.conf.

See this thread: Midi connection manager, it should contain everything you need to know.

Keep in mind that when activating ORAC, the config from /usr/local/patchbox-modules/orac/amidiauto.conf gets copied to /etc/amidiauto.conf.



ok thank you! i jump to the thead because it’sstill not totally clear to me!



Ok I’ve got cvtools installed and working with pisound. Still kinda scratching my head on how routing would be done for the left and right inputs. As one for note, one for mod. I’ll keep twiddling.



What are you trying to do precisely?

Note: The pisound hat is not dc coupled so won’t work for cv
I’m using an ES8 but any dc coulpled audio interface should work.



I swear I read it was, must be the Mandela Effect. It does seem to be working. I’m not sure how well for pitch since I have been trying out with an SQ1 by itself.



Outputs are dc coupled, input ac



The Pisound’s input is AC coupled, the output is DC coupled. However, keep in mind that audio outputs usually don’t provide the entire CV voltage range, Pisound should have 0~2.5V output range, so you’d have to additionally scale it up to 0-5V or whatever range your system uses.



Hi, i am a Beginner with Orac on RP3+ from Berlin,
so i have no Ideas anymore.
Installed Patchbox, Updates, Orac Modules on the RaspberryPi with PiSound
Can hear the Drumloop and Midi Keyb.
But in the Main.PD nothing choose the modules like in Mark‘s Videos. Only the Drumloop is playing.
I dont no whats is my mistake.
I saw all the Intruction Videos from Mark
Can anybody help?



Running Orac 2.0 in console mode - how can I find/get pd’s console log output?

Answering my own question from a tip elsewhere: journalctl -u orac

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new Orac wiki for documentation
Orac Wiki

its a little bare bones at the moment but hopefully we can flesh it out.

note: this is a community effort, so please feel free to edit/update it.



Hi @thetechnobear
I have one simple question, I couldnt get it through the Manual:
Can I use ORAC as a Audio FX Module, for example when I just want to
apply some Delay/Reverb on my Guitar which I chain through pisound?


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Yes, is the simple answer :wink:

To get audio input , turn up audio input gain on one (or more for parallel effects) of the chains in the router module.