Chirper to eurorack

[bmot]

(Edited for clarity)

I’ve asked this question before, but before I started eurorack. Apologies, and thanks for your patience with me.

It’s about grounding the chirper. I know that it needs a common ground, with 0v connected to any other desktop instruments I connect to it for control/modulation. What about with eurorack? Would I need a common ground for all modules separately, or are they all grounded „together“ if they’re in the same rack with the same power supply? I’m imagining this, but not confident so need someone to confirm.

Simple usage scenario: say I want to use an envelope from Stages with the Chirper, and also connect to Maths for modulation. I’m hoping I just need 0v to one of these, as I think eurorack has just 1 common ground, right? If so, does that work simply via any output from the eurorack modules, creating the ground? Then let’s say my desktop sequencer, which is not in the rack, is sending triggers to the maths. Do I need common ground from Chirper to the sequencer too?

Final scenario, I want to connect Chirper separately to the sequencer, say for typical pitch cv and gate. Plus I want to modulate Chirper with maths and/or another module, one of which is also connected to the DFAM. Do I need to establish common ground with both the sequencer and the modular - and what about the DFAM? If I do need to create common ground between 2+ devices, what’s the best way to do this? So far I’ve only been connecting it to my sequencer, not to 2 devices at once, so it’s been simple.

[BananaPlug]

The Chirper has one 1/4" output jack. If you plug that into a jack on a module in your eurorack that will provide the ground connection between the Chirper and your eurorack. The one exception I can think of is that a passive panel (e.g. a panel of 1/4 to mini adapters) isn't connected to your power supply so that won't make the connection.

[BugBrand]

As mentioned on my Interfacing with Bananas page

especially at the bottom...

..the interface cable approach generally works very well but is not electrically ideal. Really you want all equipment 0Vs to be joined with as low a resistance as possible, but using a connection via a jack socket is never going to be the best way to achieve this.

The banana 0V socket provide a convenient & reasonably low resistance connection point – this can be joined to other banana systems for example, which should usually feature a 0V socket on the case.

In my own setups I have all reds & blues mounted in Frames, each of which has their 0V sockets connected with banana cables allowing free patching within the system. External sequencers etc. are then connected with the interface cable approach mentioned above.

Within the modular, it all shares the same 0V so best is to instal a solid connection point to the distro (ideally where power joins it) - as suggested, a banana socket is a good approach. Then put a cable to join Chirper to the modular.
For some small external box then use a 2-wire interface cable first to again establish a common 0V link - it is, frankly, fine in such situations.
I say 'reasonably low' resistance via banana sockets because Graham Hinton has suggested superior but bulkier dinse connectors - something I've not yet found to be necessary in my own use.

[bmot]

Oh ok, that sounds easier than I'd feared, thank you both. So if i got this right i can just plug the audio output from Chirper into an input somewhere in the modular and that'll be a good enough reference point for any other connections to and from the modular. Then I can just patch cv and gate from/to the Chirper and external sequencer. Nice!

Edit: but Tom suggests installing a banana socket in the case, not sure I could do that safely. If the audio out method is fine I'll just do that.

[BugBrand]

Oh ok, that sounds easier than I'd feared, thank you both. So if i got this right i can just plug the audio output from Chirper into an input somewhere in the modular and that'll be a good enough reference point for any other connections to and from the modular. Then I can just patch cv and gate from/to the Chirper and external sequencer. Nice!

Edit: but Tom suggests installing a banana socket in the case, not sure I could do that safely. If the audio out method is fine I'll just do that.

No, as I say, that is a less than ideal / shonky way

Either install a banana on the back of the case or make a blank panel (eg mod a multiple or such) - then connect this to the input of the distro 0V within the case.

[bmot]

Sorry to keep banging on about this, but I just remembered the Low Gain format jumblers, which look really useful for what I’d need. Specifically, I could connect my sequencer, eurorack and a few desktop synths simultaneously. Ok, so I agree it’s more than i need for just one small banana instrument, but I am concerned about doing diy with electrics and just want something simple for multiple options. I was looking at this one

https://schneidersladen.de/de/low-gain ... cs-utl-1-2

Would that be safe, and work for this?

[lud]

That would work, what format jumblers are designed for - and would give you a good reason to buy more banana gear!

[bmot]

That would work, what format jumblers are designed for - and would give you a good reason to buy more banana gear!

Haha, exactly my thoughts too. Thanks everyone for the explanations and answers.

[northerntao]

There are cheaper ways to do it, but I have one of these in my big Eurorack case. I have a stand-alone jumbler for other stuff, and a few of Tom’s 3.5mm to banana cables, which work in a pinch.

https://www.perfectcircuit.com/meng-qi-brass.html

[bmot]

That’s pretty nice. I was lucky enough to find a low gain box for a good price here in BST, and being a small stand alone box I’ll be able to use it with several non modular things as well as eurorack. Problem solved