The ±12V ones Antoine was talking about are dual DC supplies, see e.g. the “2 output” category here (that page doesn’t seem to have any AC bench supplies, so not sure I agree that’s a standard feature, but maybe we’re talking about different things).
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No, I am not, you can get both AC/DC in one power supply. OR JUST AC!
That is because you look at DC power supplies, when it is AC that is needed, that is not the same thing, and would not give the same results. As search world like AC Power supply would wield a lot of relevant results.
I am talking one of those, but this unit are European/International market, not American.
https://www.sagitta.se/artikel.php?id=454#.XnfMchDQhPY
They are usually not cheap, and they are extremely heavy.
I found a quite cheap one, for American market, that is assempled and tested:
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I made a ‘ghetto’ power supply…
from bits I had laying around. Using it to charge a lithium pack here. Put the DC - DC module on the fan grill for extra cooling. Just drilled and mounted the breakout board directly on top of the box. Put a couple of strips of velcro loop under to stop it scratching what I put it on. (I know it’s not AC, but I’m working on that).
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On the AC side, a variac and incandescent light bulbs switched in to limit current. Lower power bulbs for less current, higher powered bulbs for more. It’s a solution that would look pretty cool and steam punk!
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Has anyone used or investigated or used the meanwell rs-32-12? Seems to be beefy enough to use beyond the bench and it suuuuper cheap available at mouser.
Cheaper than the meanwell rt-50b which has both 12v and 5v rails. From what I’ve read the 5v rail if not loaded creates noise.
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RS-35-12 is a single rail supply, so won’t exactly help if you need dual rail ±12 V.
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Unless, of course, you get two.
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Kind of ruins the “cheaper than a supply that costs 60% more” angle, though 
(but ok, you get more 12 V amps).
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Gratitude for responses. Buying two is still pretty dang cheap and doesn’t have the unnecessary 5v rail. Open to other suggestions?
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I took a gamble on the Nozoïd design too, since those modules are super cheap.
An Aliexpress seller seemed to have one with all the proper characteristics, but it turns out they sent me a revised revision: JM21RP LM2596S, HW-411, despite advertising older specs.
Sadly, I’m not getting it to work. When wiring two supplies as indicated, my bench PSU goes into CC mode and drops the voltage, which seems to indicate it’s shorting.
I saw online a different way to wire them up to get negative voltage:
I have not tested it, but even if it worked, I would not trust the resulting contraption too much.
“Super cheap” is more a warning sign than a virtue especially when it comes to power supplies. Trying to cheap out on power is almost always a mistake.
@ehisforadam reported three Nozoïd supply modules blowing up before he gave up on them, link above and this:
Apparently no synth modules (or users) damaged in these disasters, fortunately, but I still would not let one of these things anywhere near my synth.
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Since this topic’s come up again, I’ll mention I bought this about a year ago:
These seem to be available new for $170 to $200 or so. I bought mine used from here:
They’re not showing a price, instead a “request quote” button, but when I bought mine it was $60. A steal. It was in excellent condition, just a bit of minor cosmetic discoloration, working perfectly. Two variable voltage 3 A supplies (can be set up as ±12 V — tie one side’s negative post to ground for +12 V and the other side’s positive post to ground for -12 V) and a fixed 5 V supply, variable current limit.
Same vendor has a lot of other DC supplies, used and new; looks like you have to request quote on any of the used ones.
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Oh wow, $60 for a HY300F-3 is awesome 
I use two of these Korad KA3005P – which is (P)rogrammable via USB/RS232: Korad KA3005P Labornetzteil, 109,00 € - Welectron The KA3005D is non-programmable and around 20 Euro cheaper. I paid 90 Euro a couple of years ago for the P-model, but now they got a bit more expensive (around 100-120 Euro), but it’s a really decent PSU with very good performance for the price. Here is an old review from Dave/EEVblog:
I really like the display which has basically zero latency (in contrast to some cheap PSUs with LCDs). The PSU can be calibrated for both the voltage and current limiter and the memory feature is also very handy.
There is also a combined one (KA3305P) for 230 Euro, which contains basically two of these linear PSUs and a third one with fixed voltages (3.3V and 5V): Korad KA3305P+ Labornetzteil (Sicherheitsbuchsen), 269,00 € - We but I prefer two distinct devices in case I need to put one somewhere else 
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I realize I posted about those deprecated Nozoïd design in the wrong thread, haha, since they were mentioned in multiple ones and this was the most recent mention.
But yeah, I also tried another similar module I forgot I had, the correct board without the HW-411 REV, but a JM08RP LM2596S-ADJ. That one too doesn’t work, just draws as much current as it can. Those modules are definitely too much trouble even for a small test rig. You need the exact specific version from vendors who frequently switch components.
Speaking of bench power supplies, when I bought mine, I found it much more affordable to simply buy two single-channel supplies instead of a dual-channel one, when I researched the question back then, I didn’t find any reason not to go this route.
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I requested a quote from them for the supply + shipping to my UK address.
You really have got a bargain on your hands.
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Here’s another approach that I hadn’t considered, admittedly quite DIY - but I think I have an old ATX PSU hanging about not doing anything:
https://hackaday.io/project/184598/instructions
Edit: https://www.electronics-tutorials.ws/blog/convert-atx-psu-to-bench-supply.html has some more details
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Kind of an old thread, but I’m getting into building modules and I wanted a power supply before building anything.
Found these two adapters that output 12v DC 2A each one, and I was wondering if it would be of any use for a DIY PSU.
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An erroneous posting…