Switch on back of SMX3

Hey, I think I saw this answered somewhere but can’t find it now. There’s a toggle switch on the back of SMX3. What is its purpose? Factory testing? Does it matter how it is set for normal operation?


it’s to select between the 12v barrel connector and the euro power

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Thanks. The FKG3 doesn’t seem to have one.

It’s disappearance is more the result of an evolution of iterative development of the power module from one design to the next (PSU → PSU+Sync) and minimizing/standardizing form factors in the process.


My switch was on barrel power when I received it, and thought mine was defective for a day or so when I installed it and it wouldn’t power up via the modular. It was easy to figure out eventually, but would be nice if the rear power switches positions were documented somewhere. :wink:




Yeah it is odd because there’s no labeling on the switch. Thanks!

Oh nice! Would be nicer if there was a short manual in the box, or if this info was on the product page, I hadn’t thought to check forum for that info. But this is great thanks!

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The switch either points towards the DC barrel connecter or the eurorack power bus connector.

FYI: if you’re using the LZX 12v barrel power with your MemPal, it needs to also be connected to its ribbon power. Documentation on the barrel power module and each module it supports (plus switches, whether they also need ribbon power, etc.) needs to be documented and provided to customer. Please!

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Powering Memory Palace via 2.1mm DC Barrel

Memory Palace requires connection to the power bus (as it has a small negative voltage pull), but using the DC barrel will take care of the module’s +12V needs.



This MemPal 12V barrel implementation is also documented in the User Reference Card supplied with the module/ available for download at:

User Reference Card

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