Orac : open source instrument thing ;)

Ahh well that at least narrows down my options for now. I’ll probably go with Bela for this first project.

As far as the Marbles idea, the thing I had in mind would have t1 and x1 “hardwired” to 1 instance of rings strum and v/o inputs, and then a second instance of rings on t3, x3. So really just using it as a sequencer, not a modulation source for anything else. I do see that you have a few interesting sounding sequencers already up in running in Orac. I’ll check those out to see if any combination of them gets me close enough to what I’m envisioning.

Orac news

a little bit of news…


One of our fellow orac users, Ben Norland has kindly designed a logo for Orac, which I’ll be rolling out over next few days :raised_hands:


he has also designed a number of variations, which will be being used in other places… which Im also looking forward to using.


the guys at Patchstorage have given Orac its own ‘platform’ , which we will be migrating all things Orac over to … this will make it easier for users to find new modules etc.



Also, 2.0 is out of beta, and has been for a while.
(I don’t think that’s actually been mentioned here yet.)


Hey everyone! I have released a web client for the ORAC 2.0 - it runs on the Pi, so you can just open it up in your browser and you’re good to go. Installation instructions and more information is here on GitHub. I will appreciate any comments/suggestions/bug reports, hope this is useful!


this might also interest some :wink:


note: the orac support half way down the page…


What’s better than a virtual modular? a hybrid modular :slight_smile:

Ive been working on a new set of modules for Orac, called (un-imaginatively) cvtools
more details here:

basically what you’d expect, support for cv clock in/out, note in/out, modulation

its a lot of fun linking up the Organelle to the modular… lots of possibilities.

oh, this also works on the rPI too :slight_smile:


looking these over, it appears that the cv tools will work on any computer using vanilla and a dc coupled interface?

Well they are orac modules , so that’s how parameters are controlled - but for sure, orac is cross platform too :slight_smile:

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I’m also looking at building a custom ORAC “instrument” based on the rPi platform, but I’m a bit stumped on the right way to implement it.

I want to have keys, 5 encoders, potentially multiple displays and a bank of potentiometers (pre-mapped to the Px slots?) and I’ll use an Arduino or similar for most of the IO, with a serial to midi/OSC running on the rPi.

Is Midi or OSC or a combination the best option? Can you control ORAC menus via Midi? And the Aux button?

Should I modify the ORAC mother.pd (pi or organelle) or MEC? I’ve looked at MEC and it’s a bit daunting as to where to start?

Also, I created a quick script to update an oled i2c display via MEC display OSC and had issues with the menu overwriting the file list. It’s also a bit slow but that’s likely an implementation issue (update on every text message)

there are a few options :wink:

first, I recommend you get used to Orac using the the remote display options Ive provided for the rPI,
as its important before you do any kind of implementation that you understand Orac from a user perspective quite well…

once you have done that, you will understand MIDI is used for notes, and also midi learn of parameters - this is a ‘user level’ function, there are also some extras for mapping things like Aux key and expression input etc. (see router)

the principle idea being you can control Orac ‘headless’

then we move on to ‘providing a UI’ , this covers everything from controlling parameters, to selecting new modules, saving presets etc etc etc.

here there are currently 2 options…

a) quick n’ simple - OscDisplay
this is the interface the Lemur and PD client patch use, its very simple to use, since basically you can send and receive OSC messages to just control the ‘menu’ and parameters.
but its kind of like a ‘dumb’ client - the workflow is already dictated, you dont have to be concerned really with how Orac work, or providing a UI for browsing modules - its all done for you.

I’d recommend you start with this one, to just get you going…
(it’ll also means it feels very similar to organelle etc)

so the limitation of OscDisplay , is it makes lots of assumptions about how Orac is going to work, and how the workflow is… e.g. a central menu - this is what makes it so quick to build new clients,
you only need to deal with a few messages and bang you have all the functionality of Orac

b) full OSC control
Orac itself has a full OSC implementation to do pretty much everything, this is actually what MEC uses to talk to Orac and then is able to implement OscDisplay, and also a Push 2 interface.
this OSC interface makes very few assumptions on how you are using Orac, so you could do things like have multiple displays - or make use of dedicated buttons… have a display of arbitrary size.
(if you look at my Push2 demo, you will see that the UI on the Push2 looks nothing like the Organelle UI)

the downside is there are a lot of messages, and currently as Im the only one using it… its not documented that well… so you pretty much have to grok the code, or use something like oscdump to see what messages are flying.
also… your ‘app’ will need to be able to handle state e.g. meta data is sent about what parameters there are on a module, and what modules are available - you need to be able to keep that, for display purposes. (whereas OscDisplay is ‘stateless’ so much easier to use)

if you are going to use this OSC interface, you’ll also need to have a much better grasp of how Orac is used, and also a little more about how it works.

do you need to put your extra code in MEC? no not really, but if you know C++ it might be easier… as you could potentially reuse some of the existing code there - e.g. you might find some of the ‘state’ handling useful.

as with all programming, lots of different ways to do it, depends on your skills, and time available and how ‘integrated you want it’ on which way is best for you.

a couple of small notes:

  • I’m going to be adding supports for Fates shortly, so the implementation of that may give you some ideas.
  • I plan to reorganise the MEC device code (OscDisplay/Push2/Organelle) a little bit in the future, to make them a little more consistent, and allow them to either live in MEC or PD directly (in KontrolRack)
  • I don’t have much time for support of this till about Mid Sept due to other projects
  • I know I should write up the OSC messages, and I plan too - but its not happening for a while, due to my other commitments.

Thanks for yet another very detailed reply. I have been tied up with work the last few days, so hopefully I have a chance to sit down and investigate Orac and MEC some more later this week.
I should get my rPi sound HAT in the next day or two (a respeaker pi hat) looks like a promising “budget” option thats not the internal sound and it is also a similar chipset to the one used for fates.

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To answer pfigs question in the fates thread, is a RPi 3 b+ Sufficient to run Orac or do you need a piSound pihat?

You can run Orac just fine on the RPi alone, but the onboard headphone out is 48khz 11bits (at max alsa volume) which is “passable” at best.

So any usb or audio piHat will be a benefit and piSound while it’s twice the price of the RPi, it is a good choice feature wise. I can’t recommend this option due to these shortcomings.

Personally, I’ve opted for a budget respeaker 2.0 piHat, it has on board mics, but sadly the line in is not connected. And there is also no midi.

In short, most piHats and any RPi supported USB audio devices should work fine with Orac and be far superior to the default headphone connector.

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Is there a place to see what kinds of patches or example projects people have built with Orac? I would like to use it to create a synth style computer (preferably on a FATES board eventually) to built a sound making synthesis machine that is malleable and plays well with others.

Is there somewhere I could see/hear some stuff folks have put together?

Maybe this thread on Critter & Guitari’s forum:

Or even just browsing through patchstorage.com, many patches from the organelle have been ported for use with orac.

Orac is a framework to use multiple pd patches in tandem as if each pd patch is a module in eurorack or an effect pedal in a guitar setup.

Loopop’s youtube review may also shed more light


Thank you VERY much! This paints a much more clear picture for me. These tools are incredibly flexible, but their greatest strength of flexibility becomes the biggest hurdle to on-boarding. This really helps tho!


Great! Glad to help.

It can be overwhelming and exciting to discover all this amazing new music tech and community full of lovely, amazing, inspiring people here; just don’t forget to stop and smell the roses of the gear and tools you already have in front of you.

Or am I just projecting?


I know exactly what you mean. I actually only had a computer, maschine and a grid for 10 years. Have upgraded to an OP-Z and home made norns and realize that my limited pallet prevented me from ever really pursuing this hobby. I can see why buying gear can feel both liberating and eventually paralyzing. I think Orac will be a fantastic noise maker for me, something I can use with the OPZ and Norns/grid. But damn if I’m not already thinking “what about an OP1? Or a Digitone? Or a modular???” Haha

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this is very much my personal experience too…I find it very easy to get distracted by exploring all the wonderful options we have today. not only do we have so many great individual pieces of kit, but having more than one instrument means we have a bewildering array of combinations.

its definitely something I’m trying to be more aware of, as in some ways this was a trap i fell into with software - so many VSTs being released/updated/extended on a daily basis - i found i only ever scrapped the surface of a ‘choice few’

thats not to say its bad to explore new options - it’s something I really enjoy doing (and enjoyment is my main goal!) - but something i personally i try to keep an eye on… that im not just continually chasing the next thing :wink:

yeah, im with @JaggedNZ on this … the internal soundcard is ‘problematic’, so its best to use something else… be it a ‘hat’ or a usb soundcard, your choice.
the PiSound is a good, since its well supported(*), has midi din and is ‘reasonably’ priced, but there are lots of other options - that depending on your needs may suit you better.

orac doesn’t care, all its needs is a properly configured soundcard on the rPI.

(*) many people turning to rPI , are not ‘into’ linux, and this can be a bit daunting at times - so having something working out of the box , with someone you can turn to if you have issues is important - and blokas (pisound) are excellent for this … imo, i think a few extra $ for that is worth it
e.g.bare in mind, they are also behind patchstorage.com and the patchboxOS.

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So has anybody else twigged that Orac was the name of the sentient ship-computer in Blakes Seven?

@TheTechnobear are you a B7 fan?

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Indeed, loved it as a kid :slight_smile:

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