Finished Pieces

Mini-Modular Noise Synth

    The mini modular synth is a series of 4 circuit boards that offer a range of signal generators and processors.
    The boards are designed to allow arduino style control “shields” to be connected via a row of input and output headers on either side. These control boards will hold miniature potentiometers and a bread board style patch bay. The emphasis of this design is on compact scale, sound experimentation and circuit development. It is not a traditionally “musical” synthesizer and is much better suited for making abstract sound patterns than it is funky bass lines (although it can do funky if you get creative). I am able to make the circuits small and cheap by opting out of including features like 1 volt/oct tracking and exponential signal conversions. Those features are replaced with tons of voltage control and lots of ins and outs for cross modulating craziness.

    tested the VCF,VCA,VCO board and the S&H, RING MOD, RUNGLE board. It all works!
    Now to test the touch controller. fingers crossed

    I have assembled and tested the QUAD VCO. So far so good!

    The boards are in and building has begun.

    1. QUAD VCO (wide range VCOs from LFO to audio)
    2. VCO/VCA/VCF (single voice module)
    3. S&H/RING/RUNGLE(modulation and complex sequencer)
    4. TOUCH CONTROL,PROGRAMMER (touch controlled voltage and preset bank)

    stacking control boards
    Layout is standardized to allow easy connection with stacking interface and control boards, or jumpers can be run to panel mounted hardware on a custom interface.
    The stacking control board will enable the builder to connect all external hardware simply by plugging the control board on top of the module.
    I will design these once the PCBs have been tested. All pots and switches will be mounted on the board and I intend to use Arduino style headers and bread board jumpers for all modular signal patching which will make this a powerful and very compact system.

    *For all intents and purposes these designs can be considered UNTESTED and will most likely be modified. I will remove this note once they are tested and confirmed fully working.*

    QUAD VCO V1.1

    VCO/VCA/VCF V1.1




    Sorry, no sound files for this piece.

    25 Responses to “Mini-Modular Noise Synth”

    • 1

      noober said:
      May 26th, 2012 at 7:54am #

      yummy! very curious about the touch control thingie… will it be something à la SKB/Buchla?

    • 2

      casper said:
      May 26th, 2012 at 2:23pm #

      Yes the touch controller is very buchla based. It’s pretty experimental though so I’m not certain it will work. I’ve built both sections separately but not together. And the board layout is kind of bonkers. It’s very tightly packed which I’m worried could cause problems. We’ll see.

    • 3

      Steve Modularland said:
      May 26th, 2012 at 8:31pm #


    • 4

      amsonx said:
      May 27th, 2012 at 2:03am #

      amazing news ! I’m very curious too about the touch thing , look forward for this

    • 5

      casper said:
      May 27th, 2012 at 7:12am #

      No sir, these modules are NOT 1V/oct but they’re close to it. I think the VCOs are more like 1v/11 notes.
      Its something I’ve thought about a lot. These circuits are somewhere in between the new style of modular noise “lunetta” synths and traditional modulars. I’ve sacrificed many standardization and response characteristics in favor of compactness, low cost and quantity of modules per board. For instance I never could have fit 4 VCOs on one small board like that if I included 1v/oct and other features found in traditional musical VCOs. That said if the demand is there (which i suspect it is) i will probably design a precision VCO board for this series that holds 1 or 2 high quality VCOs.

    • 6

      casper said:
      May 27th, 2012 at 7:14am #

      I’m curious about the touch thing too! I hope it works.

    • 7

      Champagne Sequins said:
      June 5th, 2012 at 6:42pm #

      sounds radular.

    • 8

      Clarke Robinson said:
      June 6th, 2012 at 7:02pm #

      Looking forward to seeing/hearing more of this. Have you considered making the modules +/-12v? These could become *very* popular if they were compatible with Eurorack.

    • 9

      casper said:
      June 6th, 2012 at 8:00pm #

      I’m pretty sure they should all work fine on +/- 12. The only issue I know of is that the CD4021 CMOS chip has a max operating voltage rating of 18VDC. This could be easily addressed by adding 9 volt regulators to this board in the proto area and everything else could run off 12V. I’ll have to check and confirm though.
      I’m getting the PCBs in the mail tomorrow (!) and will be posting pics, vids, etc hopefully reporting on my success.

    • 10

      casper said:
      June 6th, 2012 at 8:02pm #

      Thanks! I’ll be assembling tomorrow and posting pics and vids in a few days

    • 11

      Charlie said:
      June 19th, 2012 at 7:05am #

      wow! have just come across your projects and am hugely impressed. been looking for a first project to get me started in the world of diy and thought your drone lab might be it but now i’ve seen this and my interest is piqued…

      will you be releasing this as a kit when it is finished?

    • 12

      Clarke said:
      June 22nd, 2012 at 11:52am #

      What size are the PCBs? What do you use (or suggest) for contacts on the touch controller?

      Seems to me it makes more sense to offer PCBs first, let the DIY community beat on them for a while before you release full kits or built systems. But you have more experience at this than me… 🙂

    • 13

      casper said:
      June 23rd, 2012 at 11:55pm #

      Hey Clarke,
      I think that is what I will end up doing. I will do at least one more big revision order then probably just sell the board for a while. Its a really easy build and all the I/Os are available as a header strip so it’s very easy to bread board. You don’t have to build out a whole interface in order to play around. anyway, I hope top have the revised design ready soon.

    • 14

      Clarke said:
      June 24th, 2012 at 2:06am #

      Sounds great! If you’re doing a big revision, can you make sure the PCBs are no longer than 4″ in the long dimension? That will make them easy to fit behind a Eurorack panel. I’m in for (at least) a Touch Controller and a Rungler!

    • 15

      Krz said:
      June 24th, 2012 at 5:17am #

      Any chance of battery powered-ness for portability’s sake?

    • 16

      casper said:
      June 24th, 2012 at 4:27pm #

      Sure. It will most likely be available as a PCB that you will build yourself in which case you can power it however you like. The whole thing will run fine off of 2 9 volt batteries.

    • 17

      Matt said:
      June 27th, 2012 at 12:30pm #

      This is so awesome, it’s exactly what I’ve been looking for. Do you have any idea when kits or boards (or whatever else) will be available? I was thinking of putting together a eurorack modular for awhile now, but I may hold out for this instead.

    • 18

      Matt said:
      July 7th, 2012 at 1:51pm #

      Eh, was that a reply to me? I totally get what it is. I actually prefer the direction you are going 100%, I don’t care at all about 1v/oct, I just want to patch cables and make weird noises, compactness and flexibility are what I want too, that’s why I would prefer this to building a typical modular.

      I was just curious about the timetable for the PCB’s being available for sale, because I was considering getting PCB’s made myself.

    • 19

      casper said:
      July 7th, 2012 at 2:02pm #

      Hey Matt. No that comment was not for you 🙂
      I was replying to an older email. For some reason I thought it said who i was responding to when I hit “respond”…. but it doesn’t.
      I’m not sure when it will be available for sale. The boards all work but some need quite a bit of work. Needless to say I have to redo a bunch of the layout and order new boards. I’ve also done a whole lot of system wide modifications like consolidating values across all the boards for a lower overall parts variety. Like you don’t want 51ks on one board 50ks on another. A bunch of other stuff too. I would love to wrap it up soon. we’ll see. If you are feeling VERY adventurous, email me off list and I may sell you one of the highly flawed beta boards, but I really cant get too into explanations and debugging and all that so you’ll be on your own.

    • 20

      oli said:
      August 17th, 2012 at 4:06pm #


      do you have an idea when it’s available

      and the price for the 4 pcb with shipping ?

      i wait really this project ,best continuation

    • 21

      Filippo said:
      August 18th, 2012 at 12:35pm #

      nothing new about this project? I want to build one so bad 😉

    • 22

      Oden said:
      January 28th, 2013 at 11:09am #


      When will this beauty be ready for the market?
      I love it already 🙂


    • 23

      casper said:
      February 23rd, 2013 at 3:50pm #

      @Oden: I dont think I’ll be producing this for sale any time soon. sorry.

    • 24

      nick c said:
      April 20th, 2013 at 9:03pm #

      That’s a real shame. After all the fun I’ve had with my Drone Lab 2, I was really looking forward to getting my hands on one of these =(

    • 25

      Jason said:
      October 21st, 2013 at 5:26pm #

      Hello, any chance of posting the cad files for a diy etching project? I would love to try some of these modules.

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