CV + Organelle. Is this possible?

#1

I don’t own an organelle. I’m very interested in owning one - but I’ve got a critical question. I apologize if this is already discussed somewhere. It seems like an obvious question - and yet for all my searching I can’t find a clear answer: Does the organelle’s “foot pedal” input take control voltage? And I suppose - as a shot-in-the-dark followup: Can the organelles audio input take sub-audio-rate/dc-offset control voltage signals?

I’ve read the manual - which has a “note” says this:
“If an expression pedal is connected, your patch should receive a continuous
range of values. In our experience, various expression pedal models and
settings tend to deliver different ranges of values. This can be addressed at
the patch level.”

…which I guess suggests that variable values can be received at the pedal input port. It’s pretty vague though. And throughout the documentation the input is referred to as the “foot pedal input”. Which seems like a weird way to refer to a multi-purpose CV-able input. Also - it is possible that an expression pedal could deliver a range of values not by modulating a voltage - but through providing resistance. So the ability to take an expression pedal does not necessarily mean CV will work. This makes me think maybe it doesn’t take CV? But it can take an expression pedal and deliver a fluidly variable value to patches? Most simple guitar pedals that take expression inputs can handle CV at those inputs (at euroracks +/- 10 volts, but usually at 0-3v or 0-5v). Does the organelle do this?

Secondly - as I mentioned above - I suppose it’s also possible that there is no filtering of DC offset coming in at the audio inputs - which would mean that one (or both) “audio” input channels could be used as CV inputs. The same applies to the outputs. Is DC offset filtered out of them? Can I generate - say - a sub-audio-rate LFO and send it out one of the organelles outputs?

Overall I’m a bit stunned this information isn’t more readily available - given the electronic music culture the organelle was born into is so infatuated with the modular paradigm - and given that the awesomely flexible/DIY nature of the organelle would pair so marvelously well with the ability to integrate it with other gear.

So what’s the story - am I missing something? I FEEL LIKE I’M TAKING CRAZY PILLS!!

#2

The short answer is there is no CV input / output on the Organelle.

All of the audio ports are AC coupled, so they won’t pass DC. This is usual for audio in / out.

The pedal input is an analog input, but it has a pull up resistor (10k) internally so that it will work with a foot switch. Some expression pedals work like this (such as the Line 6 one), others not so well. The jack was always for a foot switch, then we decided to wire it to an analog input so it would work with some expression pedals as kind of a bonus.

It would be cool for Organelle to have CV built in, but for now CV can be achieved with a wide array of MIDI to CV modules:

https://www.modulargrid.net/e/tags/view/10

#3

Is there a list of expression pedals that are suitable for the Organelle?

#4

I remember people saying they had success using a Korg SQ-1 to sequence the organelle while syncing to CV.

#5

I have a Roland DP-2, works great. Pretty sure any standard momentary switch with a 1/4 jack should work.

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As far as CV, that’s another story. Likely you’ll need to get creative with an external interface for that. Something like the OP-Lab for the OP-1.

#6

The Korg SQ-1 doesn’t work 100% with the Organelle:

#7

You might also use SBG from ALM busy circuits it has a CV to Expression section. I’ll try this asap. :slight_smile:

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Midi Out other than USB (SOLVED)
#8

I tested it with the SBG from ALM with the supplied cable (floating ring) as well as with a mono (Jack - mini Jack) cable. Both din’t work. Does anyone knows the wiring of Organelles Pedal input? maybe @thetechnobear?

[edit] it‘s working when you use [r exp] instead of [r fs]

#9

when i checked with a voltmeter yesterday - i thought I found = ~3v, ring = signal (return), sleeve = ground…
which seems to be the opposite of what the SBG pedal says is the ‘normal’, and this from strymon, both say its usually signal on the tip, ref voltage on ring.

but it would account for why its not working for you…
I’m not sure i want to try though, as dont want to blow up an organelle…

@oweno / @chrisk can you confirm - is organelle using tip as ref voltage, ring as signal return and ground as sleeve?
if so, a 3v pulse returned on the ring should be safe - no?

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#10

The pedal input wiring is tip -> signal, no ring, sleeve -> gnd. The signal is pulled high (3.3v) with 10k resistor so it works easily with a simple spst footswitch, but not so good as general purpose analog input.

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#11

This means the ALM cable should work (Tip->Voltage / Sleeve -> Ground). Can it be that intervals of 3V gates is not enough? Does it needs to be 3.3V? Or is i a question of the right pedal settings in the OS3.1? @oweno / @thetechnobear

[edit] an spst pedal works the same right? its just switching the signal voltage (3.3v) on/off ?

#12

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Ok i measured the out going voltage from my SBG - max is 2,5V at the 3V out.

#13

Okey, its working!! I needed to use [r exp] . Now i receive a signal flow depending on what i hook up to the SBG. I created a test patch to see if i can read out BPMs from a LFO.

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WORKS!

[edit]
this means there is a way to pass CV to the Organelle :tada:

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#14

Cool what did you change from your first experiments? Using fs vs exp?
Did a normal mono patch cable work or did you use the floating ring?

#15

Yep i just exchanged [r fs] with [r exp]. And i just tested the floating ring cable, thought it might be safer :wink:

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#16

Not quite what the original post was asking in regards to the foot pedal input - but check out what just popped up on ModularGrid…

Very very interested in this, as it should effectively give CV control of 8 Organelle parameters?

#17

OP’s post was about organelle being able to process cv signals directly, but that module looks great

#18

That goes over midi. With S.B.G. you are able to patch CV direct into the pedal input. Which was asked in this thread. :nerd_face:

#19

I put together a small ready-made patch, that you can use to complete your own patch!

cv2pd

It converts a CV-clock to [bang] and measures the time between them in milliseconds. I noticed some latency and fluctuations (~ 70ms). Please note that this patch is not a finished sequencer or such, it should serve as an aid to bring cv in to your organelle project. Also it is made for the S.B.G. module. There might be other eurorack modules which might fit. Important is that a such delivers 3V not more!

cv2pd.pd (2.2 KB)

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#20

Delay and fluctuations are expected, because [r exp] receives a control-rate signal. Control rate depends on block size. The longer the block, the bigger the perceived latency and jitter.
So while this is working, you can’t expect this to be reliable rhythm-wise.