This is a guide on how to create your own 'Pot Stand'. A pot stand is an electronic instrument that consists of 5 potentiometers connected up to an Arduino to send MIDI signals to any compatible DAW (Digital Audio Work Station). This instrument can be used as a MIDI controller for recording purposes or as a live performance aid.
Step 1: Step 1: Getting Materials
The first thing you need to do is get the materials needed to create the Pot Stand. The majority of the materials needed can be purchased at Jaycar Electronics, however a few select things will need to be purchased separately or you might have them lying around.
Things needed from Jaycar:
- Breadboard - http://bit.ly/1HL3skX
- Instrument Case - http://bit.ly/1BqDSzg
- Potentiometers - http://bit.ly/1Fi2A6C
Other things needed:
- MaKey MaKey - http://bitly.com/1FcfLVJ
- Phillips Head Screwdriver
- Electric Drill and a Drill Bit suitable for metal
There is also a couple of pieces of software that are needed for this build to function. These are:
- Arduino IDE - http://bit.ly/1oaBeGO
- Hairless MIDI - http://bit.ly/1DMxd8d
- Ableton Live (or your DAW of choice) - http://bit.ly/ShxLhd
DISCLAIMER - You do not need to purchase or use Ableton for this build to work. I will be showing you how to make it work with Ableton, however if you have the knowledge needed you should be able to translate the instructions to make it work in your DAW of choice. This tutorial is also for Macs only. It can work on Windows, however you will have to figure out how to make it work yourself.
Step 2: Step 2: Preparing the Inside of the Case
The first thing that needs to be done is measure the breadboard against the sides of the case. Once marked on the breadboard slide off the side rail, it only takes up room and gets in the way. After sliding off the rail, use your hacksaw to cut the breadboard to the size of the case, so it will fit neatly against the front of the case.
The next thing that needs to be done is attach the potentiometers to the breadboard. You can use up to 5 potentiometers (pots) in this build, for all 5 to fit they must be arranged in the format shown in the picture. To achieve the same look as my build, you must attach the jumper leads underneath the pots. The pots have 3 prongs that attach to the breadboard. The potentiometers are variable resistors that alternate the amount of voltage they allow through the turning of the knob attached to it. The way to use this to send a MIDI signal to a DAW is by measuring the difference between the starting voltage (5 Volts) and the resisted end voltage. This is done through attaching leads to the pots in different areas. The left (Input) prong is where you attach the starting voltage lead. The middle (Output) prong is where you attach the Analogue pin to read the end voltage. The right (Ground) prong is where you ground the pot. Repeat this process for the other 5 pots and then your wiring on the breadboard is almost over.
The only other thing that needs to be done to the breadboard is attach the 5 Volts from the Makey-Makey to one of the rails, attach the Ground to the other rail and attach the Analogue jumper leads into the A0-A5 (or however many you need) holes.
Step 3: Step 3: Preparing the Case
The second part to this build involves preparing the case for the potentiometers to fit through and the power cord.
The best way to measure the size and location of the holes needed is to place your breadboard with the pots attached to it inside the case up against the side you wish the holes to be on. Then with a permanent marker mark on the inside of the case where the pots turning knob touches it. After all pots locations have been marked transfer the markings to the outside of the case as you cannot drill the holes from the inside out. There is some room for mistakes in doing this so don't worry too much if the holes are off center a little, the finishing knobs you attach should cover the holes at the end of the build. Check all pots fit through their corresponding drilled holes and the turning if the pots wont be obstructed by the hole. If not, revise the width/shape of said holes.
Another hole must be drilled at the back side if the case near the screw-hole to allow the USB cable for the MaKey-MaKey to be plugged in with the case completely sealed.
Step 4: Step 4: Software Setup
Now that all the hardware is setup, its time to set up the software part of this build and see if the hardware is functioning as planned.
- There is an important file structure that the Arduino IDE needs to be able to read your library and sketches. I have uploaded this file structure and the sketches needed into a .zip folder. So all you need to do is decompress the folder and put it on a USB (It is not necessary to place it on a USB, but it makes the process easier). https://db.tt/vwRs6q0T
- Once this has been done open up your Arduino IDE and go into the application preferences (Menu Bar | Arduino | Preferences) and set the sketchbook location to wherever you placed the file downloaded (USB).
- Restart the Arduino IDE.
- Plugin your MaKey-MaKey with the USB cord provided. (Ignore any pop-up messages that appear)
- Navigate to the Tools | Board menu option and select the MaKey-MaKey option.
- Navigate to the Tools | Serial Port menu option and there should be an option called something similar to "/dev/tty/usbmodem411". There will be a "/dev/cu/usbmodem411" option as well, do not choose this option.
- In your Finder, navigate to where your sketchbook is being kept and double click on the "MakeyMakeyPlusMIDISketch" sketch. It will open up in the Arduino IDE.
- You can now press the upload button (arrow button in top left hand corner) to upload the sketch to your MaKey-MaKey.
- At the bottom of the screen when it is done you should see feedback of "Done Uploading" if the upload was a a success.
At this stage your MaKey-MaKey has been reconfigured to accept MIDI control change signals from your pots! Now you need to tell your Mac where to send that signal.
Open the "Audio MIDI Setup" Utility on your Mac. Double click on the "IAC Driver Bus" option and enable it by ticking the click box. What you need to do now is open up Hairless MIDI to see if you have wired up your pots correctly. Set the left drop down menu to either "MaKey-MaKey" or "USB IO Board" or something of the like. The top right drop down menu must be set to "IAC Driver Bus" or something of the like.
Within Ableton, goto the Preferences menu and go into the MIDI | Sync tab and enable the "Track" and "Remote" options.
Now you should be able to use your Pot Stand to send MIDI signals to Ableton!
Step 5: Step 5: Finishing the Inside of the Case
Now to finish the inside of the case.
At this stage your breadboard should already have already been fitted with your pots and the wiring required for it to function should all be hooked up and working.
The easiest way to secure your breadboard into the case is by using double sided tape. However make sure that the pots are working through Hairless MIDI before you secure the breadboard in otherwise you cannot fix that issue. Once the breadboard is secure you can secure your MaKey-MaKey to the case using copper tape, or even just a little bit of blue-tack.
Connect the MaKey-MaKey's USB cord to it through the outer hole you drilled for it earlier and secure the top of the case using the screws on the side.
NOTE - The copper tape you see on the top of my case is purely for aesthetics only. It has nothing to do with the build itself.
Step 6: Step 6: Attaching the Knobs
Now comes the final part of this build, attaching the Knobs.
Before you start, triple check that all parts of this build have been completed and are working according to plan as after the knobs are attached it is incredibly difficult to fix wiring issues.
To secure the knobs to the pot knobs I used two part epoxy applied to both the inside of the knob and the pot knob. If you hold the knob in place until the epoxy dries enough to support its own weight it will give you a more accurate seal.
Step 7: Finished! and Information
This completes this instructable on how to make a Pot Stand!
Some information to leave you with:
- To make MIDI work with Ableton, after completing the Pot Stand. In the top right hand of Ableton you will see a little box with the word MIDI in it. Clicking on the puts you in mapping mode, where you can tell Ableton what you want to control what feature. If you click on what you want one of your pots to control and then turn the pot (providing the MaKey-MaKey is connected and Hairless MIDI is open and working) it will map your pot to control that feature.
- If you ever want to reuse your MaKey-MaKey for other projects I have included the default sketch for it. You can find it in the same directory as the MIDI sketch.
- The overall cost for this project is somewhere in the ball park of $150.
Hope you enjoy your new Pot Stand!