Brilliant! Many thanks @fredrik.
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Hey, first post here. Pretty new to electronics but giving it a try. Gonna use the FC Power for sure on my first project but just out of curiosity, why canāt we use a regular āDCā wall wart? Is it a noise issue? Or would it damage anything?
Something like this:
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That wall wart will only produce a +12v and a ground/0v rail. Most synth modules require a -12v rail too.
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Makes sense. Thanks for the quick response 
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Hey, total novice here. Thinking of building the 1114 FILTER GRR from one of the most recent builder streams but have one or two qās if someone would be so kind to help me out.
- Firstly, power, I have an AC 100-240V to DC 9V 1.7A adapter, Iām assuming this isnt suitable given the +/- (AC-AC) 12V or so needed ?
-Secondly, with the correct power supply how do I connect to the back of the panel? The connection from the adapter to the 10pin connection on the back.
-Thirdly, this may be slightly silly, but the input signal to the actual panel, what are the limitation to what this can be? Can it be any audio signal/midi/ does it have to be a signal generator.
Appreciate any feedback on the above. Mucho gracias
No, the 9V adapter isnāt going to be useful.
You connect power using a 10 pin ribbon cable. Typically a power supply is connected to a power distribution bus board with multiple 10 or 16 pin headers, and a ribbon cable connects the bus board to the modules. Some power supply boards such as the Frequency Central ones will have one or more headers on them and you can connect directly to those.
Input signal is intended to be a synth level audio signal, but a line level audio signal will probably work okay. (Line level is typically smaller than synth level.) MIDI is something else entirely.
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Appreciate the quick response. My setup is minimal at the moment so I dont currently see the value in a distribution board with multiple connections and was looking for the smallest/cheapest method from adapter to 10pin (unless that is the cheapest method?). So I guess a ribbon w/connection to power supply is most suitable?
Apologies, slip of the the tongue I was using to mask my understanding or lack there of.
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If youāre just looking to power a single filter, the FC Power board plus a 12VAC wall wart will give you the Ā±12V you need, and has a footprint for a 16 pin header for a ribbon cable. And since for Kosmo modules like this you donāt need +5V, you can leave out the 5V regulator and associated components, and you can use a 10 pin header instead of 16. Then you just need the corresponding ribbon cable. Or you can just solder three wires from the power supply to the filter board and not bother with the ribbon cable.
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Legend, thanks for that!
Up to 3 modules (or even 6 with special cables) you canāt beat MiaWās PSU.
You still need a 12V AC/AC adapter. You just canāt live without one
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https://www.amazon.de/-/nl/dp/B006KG9EXW
I have two of these. Seem to do what they need to.
12v DC adapters are very common. 12VAC seem as rare as hens teeth here in the Netherlands.
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Iām contemplating issues with getting a power supply.
What I would get is for the supply between the wall outlet and the 3 pin terminal for the bus board. This supply I would need a transformer rated 117V.
I thought I had all I need with TwinTurboās power supply however I canāt find the transformer and I havenāt a case.
I just need a power supply but now that Iām saying it I need a case lol.
-Fumu / Esopus
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Getting a power supply is perplexing me and Iāll read over all advice from the topic to gain a head over the mess my head is in now. One intuition Iām having is Iāll be looking at a wall wart power supply when Iām through all the advice. Thereās one issue Iām not over is whether powering around 16 to 24 modules should be on one power supply or two. I could put one bus board or two in the modular case but it seems Iāll run out of room for modules on the bus board before I run out of modular case. Would it be efficient to run two bus boards off of one power supply or each bus board get its own power supply?
-Fumu / Esopus
if you can afford it , would be best to have 2 power supplies and 2 bus boards per case . better to under work the 2 than over work 1 . as we have seen , not having enough power will cause weird glitches with modules that are sometimes hard to trace back to being a power issue which can be very frustrating .
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So I went a little crazy with a plan I had to run some modules from a car battery and started looking into switch mode power supplies - getting Ā±12V from a car battery was the idea. Figured car audio amplifiers do something similar and started looking into that route.
I found this site: Switchmode Power Supply For Car Audio and started following along.
Ended up winding my own transformer and nonsense like that - super dodgy but a fun project:
SG3525 PWM controller driving IRF540 MOSFETs through a center tapped transformer, rectified and filtered into LM317/LM337 linear regulators.
After figuring that all that was too much faffing about I started looking into some modules, and I think one of the Doepfer mini power supplies used something similar. I found the RAC20-12DK and built a prototype. Please look away from the casual 240V all over the place - the plug has a sheath on it now and I put insulating tape on the underside of the vero-board while waiting for a proper PCB. When mounted in a case there will be a power switch on the live wire as well as an inline fuse. So far the module has been very well behaved and shuts down quickly when you inevitably short out the railsā¦
Cheers,
Jared
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Butā¦ wasnāt it to have 12V going in, not 240V ?
BTW, nice trick :
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Yeah - 12VDC for the original SMPS - but I also wanted something I could plug into the wall. Now Iāve got options!
The PVC pipe feet were a complete afterthought - now I make sure all my little boards have holes drilled in them for stand-offs before I startā¦
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Hi! I scrolled a bit over the post and I couldnāt find something about the matter, Iām sorry if this has been solved.
Iām using a build I found on the internet thatās quite similar to the Frequency Central power supply Sam builded on one of his videos. What got my atenttion is that he said that various power supplies could be conected to the same power plug.
Does it mean that I can split the output of my 12v AC wall wart to power various power supplies and theyāll still get 12v?
I also considered getting the RT65B which gets mentioned quite a lot in this post (mainly in case I canāt supply eficiently 3-4 power supplies with a 12v wall wart)
Thanks for your time and have a nice day!
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You can connect multiple āwall wartā (half way rectification) supplies to a single wall wart, provided that 1) the wart can provide enough amperes, and 2) you take care to connect the same AC line to the same input on all supplies, see:
(The typical āwall wartā supply uses one of the AC lines as ground/0 V, so if you mix this up youāll short things out if you connect ground to ground. If you mix supply boards, make sure youāve figured out which one is ground.)
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I know that there are cost issues . but a single 2 amp wall wart powering 10 maybe 12 analog modules is probably as far as you want to go [ digital boards with possessors even less ] because when you are under powering your modules they start doing flaky shit and may even sound different . or are you saying that you want to use 1 ac plug in wall to power 2 wall warts by splicing wires ? , thats fine but please be careful with the 120 / 240 we would like to see more posts from you .
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