“Ultimate Voice Changer” Arduino Shield

Do you want to sound like a Dalek or a Cyberman for Halloween? Do you want to buy the perfect Doctor Who Christmas Gift for the geek in your life? If so, this is the Arduino project for you! This is a voice changer shield compatible with the Arduino Uno that can be used for a variety of voice changer effects from pitch shifting to ring modulation. It consists of a 12-bit ADC and a 12-bit DAC plus a low pass filter. By using the external ADC and DAC, the Arduino is left with much more processing power for manipulating the audio signal and allowing for effects to be adjusted in real-time without having to restart the sketch.

The voice changer is fully open source. The source code, schematics, and board layout are all available here. I also sell kits in my Tindie store. Click here for assembly instructions.


All 8 analog channels are broken out. This means you can sample multiple audio sources and/or multiple potentiometers or other analog inputs for manipulating sounds. The board doesn’t contain a pre-amp for audio signals so you will need a mic with a pre-amp built in. I recommend using an electret mic breakout from SparkFun (product link) or Adafruit (product link). These are the mics that I am using in all of my video demos.

You will also need a speaker with built-in amplifier. There are many “portable MP3 speakers” available. You will need one with line-in input (bluetooth won’t work).

There is an on-board LED that can be manipulated along with the sound. There are also pads for connecting a screw terminal to connect to external LEDs. This could be used to drive Dalek dome lights or the mouth in a Cyberman helmet, just as examples.

Here’s a video showing this in action with the classic ring modulator sound effect.


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15 thoughts on ““Ultimate Voice Changer” Arduino Shield

  1. andygrove Post author

    Well, the boards arrived yesterday and they actually worked! I have updated the page with a video showing the new board in action. I’ve also set up a store on Tindie for anyone wanting to order a kit.

  2. Guy Jackson

    Say, Andy…did you already do your Halloween board run? I would be interested in buying a couple…


    1. andygrove Post author

      Hi Scott,

      The best way to do this is to get an audio connector and solder a couple wires to it, and connect those wires to the amplifier.


      1. Scott allen

        Hi again, everything appears to be hooked up properly and the sketch was successful, the Mic shows to be working, the speakers and amp work, but I’m getting no output from the wave shield, any thoughts?

        1. andygrove Post author

          Sorry to hear you are having issues still. I’ve sent you an email just now. I’ll help you get this working.

  3. Christopher Hunter

    Can you provide guidance on the pot terminals? For some reason I’m failing at getting the adjustment feature working.

  4. Chris Jorgensen

    Hey Andy, the voice changer works great, but the electret mic with the kit is somewhat difficult to use because I have to hold it in place. Do you have any recommendations for headset microphones or how to hook one up to the shield?

    1. andygrove Post author

      Hooking up a headset microphone is tricky because you would need a pre-amp. I experimented with this for a while and failed to come up with a good solution. Another option is making some kind of holder for the electret mic (this could be something simple like a cardboard box or something more sophisticated with 3D printing). Holding the mic or wires can definitely cause some interference.

      I just happen to sell a custom case on Tindie that might help.


      This requires a little hot glue to hold the mic in place but works really well. I’ve used this at a number of events with good results.


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