The AC-DC Power Supply thread

Equipment
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I started typing wildly about my single biggest technical problem with Eurorack in this thread about cases, and it’s about power supplies to cases. Copying and pasting my deleted missive from that thread:

The biggest headache of all is having all these separate AC/DC bricks, cords, etc. I would LOVE LOVE LOVE it if [Intellijel, @kisielk] built a modified 1U or 3U power entry module that would allow daisy chaining from one power supply, somewhat like 4MS does.

I know the lack of standardization in Eurorack once again rears its head with power supply solutions, but for those of us with a handful or more of 3U-ish cases rather than one big wall/desk unit, the power supply stuff with the AC cord octopus monster and stuff everywhere is ridiculous. Single biggest problem with Eurorack in my opinion.

All manufacturers should use exactly the same DC input plugs, provide a pair of plugs for chaining, and arm end-users with the knowledge they need to not overload a circuit. I understand liability is probably an issue here, but anyone smart enought to understand sound synthesis theory is smart enough to add up milliamps and make sure their system’s current draw doesn’t exceed supply.

@tehn, I sort of alluded to this before, but if it’s not too late, I would urge you to consider building such a solution in to your forthcoming -isms cases, as I’m pretty sure I’ll have at least two of them; I can even envision three. I’m pretty sure I’m not the only one who would appreciate being able to run a couple or more cases off one tidy power supply rather than two.

This, or as I know I said a while ago, someone pleae come out with the equivalent of a VoodLabs guitar effects pedal power supply type thing for Euro cases. One AC cord, one ample power supply (can be bigger than a typical brick), and a half dozen or so DC leads that will plug in to standardized inputs, no matter whether it’s Intellijel, Doepfer, MN, Monome, TipTop, 4MS, etc.

I like smaller, discrete instruments, not the giant wall-o-knobs. But this power supply issue is just a killer. Such a drag.

Thanks for listening!

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It would be nice to use the same power jacks, but it’s not always possible. For example we use Meanwell power supplies for our power boards. Their 65W and lower bricks use 2.1mm barrel jacks, but the 90W use 2.5mm. They have larger power supplies too, which use different connectors still.

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i’m all for love love love and lack of headaches, but before you “should” on everyone, please consider:

quality barrel jacks are rated at 5A@12VDC. most AC/DC adapters with barrel connectors are wired with too long of a length of small gauge wire for much amperage (this is why i use the mini-DIN connectors, and they also lock). unless someone wants to commit to the significant volume that would allow for efficient manufacture of the components required, if adopted at any real scale the outcome of the “should” above would most likely not sit on a solid engineering foundation at even the most basic level.

someone legally manufacturing and distributing the equivalent of the “guitar effects pedal power supply type thing” mentioned seems unlikely. having it underwritten is not cheap. it took strymon a long time to develop theirs, and the market/ROI for it is considerably larger.

i’m at least partially with you in spirit though, and i’d really like to be wrong about any of the above. but, practical limitations appear to make it what it is. maybe a bigger manufacturer like tiptop could/would do something about it, everyone else seems to be more happy making more modules that are more immediately appealing. when i started with eurorack (get off my lawn), you had to carry around a heavy and hot transformer, we’re fortunate at this point to just have to plug in a few adapters. to meet typical power needs, my largest 750hp cabinets now take just two adapters, with wiring and connectors sized appropriately. that seems practical enough to me.

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you’re not the first to suggest this. we’re taking it seriously-- particularly because the per-case amperage wouldn’t need to be too high. but we’ll see-- making jumper barrel-to-barrel cables could be very annoying unfortunately.

re: making a universal standard-- not sure anything will get agreed upon for eurorack beyond what’s already there.

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Where’s the dancing wookie emoji when you need it?

Oh yeah, I can imagine! I wonder though if you could just snag a bunch from 4ms?

http://www.4mspedals.com/barrelcable.php

I’m doubtful too. That said limited partnerships would go a long way. For example, if your cases where power-jumper compatible with 4ms row-power that’d open things up a lot!

(Ok, now back to my armchair! :blush: )

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http://www.mojotone.com/Accessories_x/Pedalboards-Pedal-Parts_x/DC-Jumper-Cable-for-Pedal-Power-Supplies-2-1mm-54-1-female-to-6-male

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Ok, FIRST OFF: I nominate this bump for necro-bump of the year, if not the decade. Discourse is asking me if I want to proceed (and yes, I do).

Secondly: Why do I want to proceed? Because I want the universe to grant me the equivalent of a Strymon Ojai with 5-6 12v center positive plugs, because every single piece of banana gear that I own operates on this same standard, and the wall warts are driving me crazy.

Surely there’s a solution out there. Someone enlighten me and save me from power strip hell.

Edit: there is. Eventide PowerMax Pedal Power Supply for Pedalboards – Eventide Store (thank you @srogers91 )

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ART ISO-8U looks like it fits the bill. With some fun guitar pedal centric tricks (dying battery simulator :sunglasses:)

Polarity issues can be remedied with reverse cables that I’m sure are out in the world.

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Technically, any power adapter can be made into a daisy chain since you can buy a daisy chain attachment cable.

The only major concerns to keep in mind with a daisy chain is voltage (in your case find a 5V wall wart), enough current for all of the devices, and that analog gain/distortion devices can be really sensitive to the noise that comes from digital devices and can output weird high pitch noises because of it.

I used to use a one-spot daisy chain for guitar pedals, but a couple times I heard a weird crackling/sparking sound coming from it out of nowhere and swore off them permanently (I have a feeling it was from one of the plugs on the chain that wasn’t connected to anything, but I have no idea I just got cagey and moved on to a more robust isolated power supply). So it’s worth keeping in mind that there’s potential for failure with any system.

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