The x0xb0x 303 clone has become somewhat legendary — a legend that’s likely to grow now that you can’t get one. Photo (CC) bdu. I need to start labeling my gear.

The x0xb0x, the open-source Roland TB-303 clone by Limor “Lady Ada” Fried, has been officially discontinued edit: unofficially end-of-lifed? Made less than widely available? It’s actually unclear. That makes this already hard-to-find kit tougher still to get. Because it’s open-source hardware, you can source the components yourself and build it, but some of the parts are very hard to find — which may be why it was discontinued in the first place. has been difficult to get a hold of in full kit form.

Our friends over at the awesome trash_audio (music blog with home studio voyeurism added in) pick up the story:

x0xb0x: Kits Discontinued

So, what’s next? It seems to me that, should the open source hardware argument really hold for music gear, the x0xb0x needs some successors — the more, the merrier. First off, perhaps it’s time to re-conceive the x0xb0x in a version that uses more easily-sourced parts. (Call it the Socks Box, dropping the l33t spelling as a metaphor for more accessibility?) And I’m eager to see the Next Great Open Instrument. Nominees?

Update: Okay, as my corrections above concede, it seems that the x0xb0x is not fully discontinued, just hard to get and between production runs. (I thought about applying a question mark to the original story, and now regret not doing that.) But maybe it’s time to declare what’s been obvious to many for a long time: the backlog for the x0xb0x is so huge, and there are so few signs of any increase in production rate, that they’ve effectively become impossible to get.

And that raises another question to me: is it possible for open-source music hardware to reach bigger quantities? Could they keep their cool factor even if everyone had one? (The answer, I suspect, is a huge yes, because greater availability almost encourages users to make their gear their own. Witness the hugely-successful Arduino, arguably music hardware itself.)

If you do get one shipped to you, though, do let us know.

Official word from Lady Ada in comments:

peter, the x0xb0x is not discontinued. the waiting list is long enough that i suggest ‘self sourcing’. i am still making kits but it is slow going.

  • something using the sid chip??

  • Video Music

    I for one would be very happy see an open source Jupiter 8 😛

    Or open source control vinyl systems. 0P3N 5CR47CH 80X anyone?

  • an open source sampler and sequencer made of regular laptop parts, thats what we need!

  • @cooptrol: I'd say what's happening with Linux and Ardour might qualify. 🙂

    Vinyl control… well, not exactly as such, though there is open source software capable of reading vinyl control.

    I think a key element is easy hackability. If it's going to be open source, you want it to be able to support people actually messing with it. Even the x0xb0x was a little complicated for this.

  • relaxing

    Not discontinued! And if you feel up to sourcing some parts on your own, you can build it yourself any time!

    From the analogue heaven list:

    To: analogueheaven

    From: limor


    Subject: Re: [AH] x0xboxen

    Date: Fri, 30 May 2008 12:20:44 -0400

    to clarify: there will be more x0xb0x kits made -but- there is no way that everyone on the list will get one and its also not clear what that timing will be.

    thus it is recommended that people who -really want one- should build their own.


  • ERS

    Been on that list for over a year now!


    "Free as in "Free your mind and your ass will follow"

    The x0xb0x will never become 'discontinued,' because it will be fully documented and released into the public domain (under an appropriate open-source license). The PCB files (schematic, board, BOM and gerbers), firmware, software and panel DXFs will be available for download. Even after we sell all the kits, you will still be able to build your own x0xb0x.

    We do this because we love you."


  • Oldtimer

    ERS: Been on that list for 12 years now!

  • peter, the x0xb0x is not discontinued. the waiting list is long enough that i suggest 'self sourcing'. i am still making kits but it is slow going. please update the post so that people do not get confused and google doesnt get a chance to scrape this. thanks!

  • yay thanks peter 🙂

  • ERS

    haha oldtimer, not the analogue heaven list, but the x0x waiting list 😉

  • poorsod

    Hey people. I have been set the task of DIY building a simple analogue synthesizer (from instructions) in the time frame of a few weeks. I figure this post would be a good place to ask if anyone knows of any decent, straightforward kits that I can source and build relatively quickly?

    I would call myself 'beginner-to-intermediate' level. I have a very good idea of how analogue synthesis works (including an understanding of a lot of the circuitry), as well as a relatively good grounding in electronics (I have designed and built a number of simple circuits on my own… thermostat-controlled fans and the like).

    I have not done anything as complex as build a working synthesizer yet, but now is as good a time to start as any, surely?

    So yeah – any recommendations for open-source synthesizer kits, that can be put together from scratch quickly and easily?

  • nkem

    ebay. x0xb0xs show up all the time.

  • I'm glad I bought my xoxbox kit last year… Now I suppose I should put it together.

  • I’ve been looking into getting the bits together to build one of these suckers, its not easy. I wish I got a kit when I had the change.

  • This is a nice post about variety of Socks and its a very needed information.

    Thanks for such an important post.


  • Joe

    I got my kit from

    They have a good supply of them and send them out really quick.

    I have built one of them and ordered a second.