DIY Midi Floorboard

  • Ok everyone, i'm not sure i'm in the right subforum, but i'd like to share a currently evolving idea i have.


    So, first things first: I need a midi board for my kemper. I have a Pod HD for that, but thats to big. The Behringer is to big too. Everything else is in my personal opinion way overpriced for what it does. I'm sure not paying 600€ to switch some profiles.
    After browsing for options, i thought that that should be doable as a diy project. After some research i came up with two options: Doepfer makes a Midi board, thats midi in/out/through plus connections for i think 4 buttons and 4 potis. The other option is arduino. There is a native arduino library for midi commands. Since arduino is cheap, readily available and the only downside (the need for programming it yourself) is irrelevant as i'm a software developer i will give that a go.


    Alright. The arduino uno has 6 analog inputs and 14 digital ones. Since i want to keep it expendable, i'd like max 15 Buttons and two expression pedals. I'f you want a display and an LED for every button you're quickly runnig out of ports. There is a bigger arduino, but i want to fit it into some kind of smallish enclosure.
    As a workaround, every button gets a different resistor. They are than hooked up i series to a single analog port. The Arduino will "measure" the resistance and by that determin the button pressed. That way you may have nearly unlimited buttons on one port. With 15 Buttons and a bit of math you are even able to sense every two button combination.


    To keep this project flexible, extendable and portable, i'm not throwing 15 buttons into a big box. The Idea is a "central unit". This houses the arduino, 4x20 display, ports for midi and expression and 4 buttons for the for rigs per performance. Additional buttons are than put into extenders. Pretty much a box with 5 buttons each. They are connected with standard mono patch cables (ground and one data for all buttons). These are infinitly stackable (nearly), and switchable in order. So they can be arranged on the pedalboard as desired. This leaves room for other formats and positions in the future (a single button mini box for Tap Tempo e.g.). The extenders are cheap to make (a box, switch, resistor and two mono jacks).
    Best thing is, the arduino is powered over 9 volts or USB. So you can use either your pedalboard PSU or a seperate batterybank/wallwart.


    The Base unit comes to around 80€. Thats mainly because of a high quality aluminium case for 30€. Thats not to far of commercial 4 button midi boxes, but with extening further, the cost gets significantly lower.


    I've attached a little "concept drawing" of my current idea. Let me hear what you think about this and how you would improve on my design. I might be missing something, since i'm not using the kemper for that long.

  • The performance works with 5 rigs.
    Even if you play with only 4 profils, if one day you play with an other band, with différents sounds, you could have some difficult :
    The 1-5 rig (pc#) ll be the 2-1 in your floorboard, the 2-5 'll be the 3-2 in your floorboard....


    The second unit (for the fx) isn't necessary : use a rig without fx and an other (next) with the fx.


    Use differents floors for each unit (it s easier for your foot)


    It you ll be interesting to add a fx loop for an external fx


    What are the "bst" and "( )"?
    How to active the external pedal?


    I search too a good midi controler and what you say is verry interesting.

  • My future project will be nearly similar. I choosed the arduino nano with using of shift registers to manage more buttons.
    I purchased a POD HD 400 cheap and will integrate my Arduino solution in it. With a switch from an old printer switch
    i can switch between HD 400 and Kemper-Arduino. So if the Kemper will get out of order i can do an emergeny switch
    to the POD and can play futher on.
    I just started the project and must pause now because i have no time. But when it will be ready somewhere in future
    i have a robust switcher for the Kemper and a reserve modeller just in case.

  • Is it still relevant?


    - have a look at the "teensy" and teensyduino. (Very small but VERY powerful Arduino with TONS of in- and outputs).


    - I did a DIY- Midi-Controller with an Arduino Mega. Works perfect and is much fun to develop! But I´m tending to use the Remote lately... :)


    Martin