DANGER: monome modules can blow up your eurorack power supply!

  • but don't panic!

    ..the limitations of your power supply are very important to be aware of though. monome grids use a lot of +5v current (up to 600mA) and until recently power supply designers were not considering this sort of 5v demand.

    recently we've heard from a few people that blew their +5v rails or whole power supplies with monome modules. every instance was caused by using an underspec'd power supply. if your supply powers +5v from the +12v rail, blowing the +5v rail might toast the whole supply. solutions like the MI volts, MakeNoise +5v adaptor, and Erthenvar Free Lunch are all capable solutions, but you need to confirm your +/-12v rails are not overtaxed as a result - they will add 300-600mA draw to the 12v rail with a grid attached.


    for best practice we strongly recommend our 'ext5v' adaptor. it isolates your grid from the case for lowest noise & current draw. you'll still need a +5v rail in your case. we're selling it direct now at a reduced price ($22) because we'd prefer everyone to avoid this issue altogether. your retailers should have updated their pricing, so let them know if they haven't. we're creating a 4HP panel-mounted version if you want to avoid the dongle, which will ship in january. the ext5v adaptor is in stock now.


    we also recently released a limited batch of 16x8 grid kits. these provide a complete solution for use with our modules at a reduced price from our walnut grids. a great way to get started with monome modules, available from the link above.

  • this post will be updated to reflect proven (and disproven) case power supplies.

    known compatible power supplies (for use without ext5v):
    - 4MS Row Power 40
    - Make Noise Powered Bus Board (Upgraded Version with 1.5A +5V)
    - Synthrotek 5A Supply (with +5V adaptor)

    these power supplies are known to require the ext5v as they don't deliver enough/any +5v current. some of these supplies might work at first, but consistantly over-taxing them can lead to failure over a longer period:
    - 4MS Row Power 30
    - Pittsburgh cases
    - Make Noise Powered Bus Board / Mini PBB
    - TipTop uZeus

  • I think you guys should be putting this info in the box along with the modules.

  • we do list all of the current requirements on the included documentation, but it seems the more info you include the less people read / appreciate. we've been asking our retailers to ask questions about customer's power supplies but most orders are online so there's little opportunity beyond clearly stating the requirements on the product pages.

    it would be preferable for people to know about the need for ext5v at purchase, rather than have the module turn up only to be told they have to order another box - i guess that's what this post is about. trying to improve the situation!

  • potential solution could be adding a jumper that would need to be set in order to enable USB power on a module. more people asking "why my grid doesn't work with the module!" vs less people blowing their power supplies.

    would also be a nice safety feature if I use the ext5v but want to make sure I don't forget and accidentally connect the grid directly.

  • the actual solution is to include the Extv5 adapter with the modules. it really should be chaps.

    you've as much as said that in your first post.

  • maybe you need a warning label like on the deopfer power supplies warning of death?

  • Not sure I agree. If you buy two modules you don't need two extV5. I think the guys have done the right thing by reminding everyone of the power requirements, the potential for damage if the power supply specs are exceeded, and generously lowered the price of the extV5 (all said as someone who didn't engage his brain sufficiently when reading the manual and is currently await a repaired MN busboard; particularly embarrassing as I already own an extV5.).

  • I think this should be in big letters on the order page or something.. or a link to here..
    (or at least make it a sticky)

  • everyone just needs to be aware of the eurorack power needs. i have some other modules that don't properly work when any more then 50% of the PSU is being used and they don't mention that at all. the information is all there, just remember this isn't totally a "plug and play" format.

  • thanks for posting this spreadsheet!

    eurorack requires you to know something about electricity-- at least that there's a max current number, and you have to add up the consumption amount for your modules. modulargrid.net will do this for you if you can't be bothered.

    we state 600ma requirement. that's the warning. we also include a full paragraph explaining the power situation. we're doing everything already. people just need to be aware that these things matter, so the stuff we've written actually gets read. which is why we posted this DANGER DANGER.

    more the point of this is that we wanted to educate people that just because something seems like it's working, there's a chance you're break your power supply over time, as heat eventually kills a chip somewhere in your case.

  • i am totally in support of people learning more about electricity.

  • i disagree with having the ext5v as a separate item though. it's like selling a laptop without a power supply.

  • @oootini what if some buys multiple modules? or has a row power 40?

  • 1 most euro power supplies cannot support the grids.
    2 grids add noise to those that do.
    3 most people should use the ext5v to get the best out of these modules.

    buying two modules doesn't come into it IMO.

  • "buying two modules doesn't come into it"

    how? if somebody buys a WW and MP that is definitely a factor

    correct me if I'm wrong but this is like asking every american electronics manufacturer to include 220v adapters in their packaging

  • @galapagoose -- would you be able to share some additional information about the pending panel-mounted version? Specifically:

    - Would it require any case power?
    - I assume it would have a front mounted power adaptor input and 2 USB inputs (one to patch a USB A-A cable into the white whale, and a second to connect a USB A-B cable into a monome). Is this the idea?

  • lol @raja
    the same principle applies

    it would be silly to buy a european/african/asian appliance or electronic device and expect them to be responsible for each units compatability (when used in US)

  • i dont really care much cause i dont have either module

    maybe actual users of the MP and WW agree that the ext5v should be included

  • yo our adapter works 220v

  • You should all definitely do electricity 101 too.

    This basically.


  • "tehn
    yo our adapter works 220v

    *the poser puts foot in mouth* :D

  • this is a great thread!

    in my opinion:
    adapter should be included.

  • known compatible power supplies (for use without ext5v):
    make noise board (upgraded version with 1.5A +5)
    runs WW+MP simultaneously, each with their own 128 in my (fairly typical) 6u@104hp, without ext5v. no observed problem. typical noise observed.

  • thanks goiks. updated above and added the synthrotek 5A supply as well.

  • I disagree the power adapter should be included with the modules. It's not free, so it would add to the cost to the module. I bought a WW and MP, why would I want two adapters, and why would I want to pay the price twice?

  • @rajatheresidentposer I love your posts and sense of humor but I've had a different experience with tehn and monome. My power supply went bad after a week and before I could barely report the issue, I had a new one shipped to my door step. And numerous simple questions answered in a positive supportive way. I'm sure you aren't totally down on monome so this is just a reminder that wonderful things are still happening:)

  • ( @abits.. no no, i didn't mean it that way. was speaking more of general 'businessy' stufff. but words fail, and i've grown abit 'busyness' meself >8D i've had troubles with 3 different monomes, but monome.org fixed all right away :) ...never meant no seriousness)

  • This could be a community supported thing. The files are up On OSHpark, anyone ordering has three as that's the minimum so start sharing and caring...

    I totally did not Heed/read the warnings...I soon after took out my 256 which needed sending back to the mothership as it was more than re flashing could fix. My Makenoise powered bus board was trashed as well, so rather than risk it, I scraped off the regulators and turned it into a passive board to join my tiptop passive and have a pair of linear old skool toroidal 12v/-12v PSUs from ericasynths and a pair of mutable instruments volts units that deliver 5v @1.5A across the two independent bus boards.

    It sucks, it's costs, you are without a Monome, Tehn could probably be doing other stuff and I have two ext5vs ready in case the current delivery is not enough.

    Still, Monome 128 grid kit here soon so the 256 stays on the lappy and the 128 stays on the eurorack...

  • @rajatheresidentposer no worries! Words fail me (or rather, I fail them) all the time. Just making sure we are all still smiling because so much of the world can't. :) be well!

  • I can envisage knocking out a nice little eurorack hub so you can hotswap say four USB ports -- the monome stays plugged in and juiced and then goes out to your WW and/or whatever wonderful ness will be next, think of it as a buffered (in more than one sense if the word) mult for maybe supporting a few grids and perhaps arcs and patch from the mult and not the source. nws::2b also, that looks interesting as does the third monome.

    arc support would be lovely. But I guess it's the smallest bird in the nest...

  • another known compatible power supply (for use without ext5v):
    intellijel's new board offers 1.5A +5

    i've run two 128s/monome modules simultaneously on this one too. will post again with more experience when i have it.

    disclosure: i sell these. i don't mention this out of self interest, just figured i should probably say so.

  • ah, they're ready? i've been talking to danjel about these. fantastic.

  • yes! been using one for a few months, but just received the first shipment yesterday.

  • Next up the Monome Ammeter Module to test your 5V supply!

  • hey it shouldn't matter which usb you plug which into on that ext5v should it? I assume that the square usb from the ext5v can go to the rectangular usb module ins and the rectangular usb from the ext5v can go the the mini usb on the grid, so that common usb cables could be used?

    Having trouble getting any response from the grid (which powers up when plugged into ext5v and functions fine otherwise with computer) when plugging into earthsea / white whale, and the latter don't seem to be working right either - ex., when I connect white whale to the grid via ext5v, the outs 1-4 blink for a second like they're starting a sequence then just stay on.

    Seems like the symptoms would point toward power being pumped down the usb I'm sending to the rack instead of to the grid but I just can't fathom why the ext5v would have the usb configurations the opposite of how it seems to make sense to use them. Thought I'd read everything I needed to get these going, and even feel like I read something here about someone mentioning how odd or cute some usb adapter looked, but can't seem to find it now. Had hoped they were talking about the 1' cord from the power socket to the transformer for the ext5v.

    Anyway, any advice would be a great help - thanks!

  • I'm not an ext5v user, but just an idea: do you have 5v on the bus? the module itself also needs 5v from the rail.

  • the modules are both plugged into the rail, red to red. if there was anything already on the white whale it should be triggering without any need to connect a grid, right? will have to look into it more tomorrow

  • the clock out I guess.

  • do you have 5v on the bus? it needs 5v. the ext5v only powers the grid, not the module.

  • you will see clock blinking when it's running, without a grid.

  • also, you need 'standard' usb cables.

    A (rectangle) to B (square) from module to ext5v
    A (rectangle) to B / mini-B from ext5v to grid

  • "do you have 5v on the bus" sorry this is my first eurorack venture - did not realize a separate power supply was need to get to 5v (guess I thought for some reason the modules regulated their own voltage - which really makes me feel dumb, since I remembered reading this thread and should have known better), I had modules plugged into 12v rail, hopefully they're ok, didn't look like they became non-functional so I'm not too worried.

    thanks all for the help - can anyone recommend a good/cheap 5v power supply? :^/

  • get a mutable instruments volts (or similar.) they're just a little dongle that fits into one of the power jacks. you'll be running in no time.

  • found a flight of harmony adapter down at robotspeak, but it only converts for one module - that is I think, it has a male and female socket which we figured meant it only converted for the module whose path you add it too. (I had the thought that if I sent a ribbon from the adapter output back to the rail I could get 5v to the whole bus, but not sure about that idea. maybe if I cut everything except 5v and ground out of that ribbon). he only had one adapter, so the w.w. and earthsea are taking turns for now. he mentioned the volts also, looks like that's the best way to add 5v to the entire rail without an additional power supply. my question then is this - how do you add up your currents? where does the 5v current supplied by the volts draw from, I guess is what I'm asking - 12v+? Clearly I'll still be using the ext5v but just for my own knowledge as I'm learning all this I'm curious. Is the current for the 5v generally assumed to be so low that it's negligible vs. the 12+/-v (making the ext5v all the more necessary)?

    turns out the lower-end pittsburgh cases don't supply 5v but all their other cases do, for anyone else out there looking at the 10.1+ beware. at least I feel less stupid for assuming that 5v would be included for any power supply built into a case that could house 5v components - it seems like a pretty logical assumption to me, especially since the bus is built to carry 5v, and it is built into 80% of power supplies, and the 10.1+ is a new product - the people who should feel stupid are the ones who didn't include 5v in the case power supply. stupid heads.

    anyway, thanks again for the assistance. everything seems to be working - and I still have something to look forward to, when I can power both units at once!