RäusperESP32

Ultraschall/Reaper Mute/Push-to-talk via ESP32 + Button (using Bluetooth Midi)

Why?

For podcasting I use the combination of Reaper and Ultraschall for recording and cutting audio.

While recording, you sometimes have the need to mute yourself (to cough, to drink, etc.). Other people actually prefer to use push-to-talk to be muted by default.

Ultraschall supports this workflow already with a cough-track that does that for you.

Now we only need a fancy button to use for muting.

What?

Required tools & materials

• ESP32 microcontroller
• Whatever you want to use as "mute-button": Foot pedal, switch, button, ...
• Micro-USB cable (for flashing)
• Power
  • Any kind of USB Power (for running);
  • Alternatively: An ESP32 that runs on batteries.
• For assembly: Soldering iron (only two cables have to be soldered)

Hardware Assembly:

• Connect your switch to GND and pin 18

Using a different pin: If you use a different PIN you have to change it PIN in the sourcecode. Check if your ESP32 provides a pull-up resistor for that PIN. Also: Check if the PIN is not used by anything else of the ESP32 and get the ID of that Pin.

Software

1. Download/clone the software from https://github.com/derphilipp/RaeusperESP32/
2. Open the project (recommendation: Visual Studio Code)
3. Change all configuration items you want to in ./src/main.cpp:
   • Do you want push-to-talk instead of mute? Change PUSH_TO_TALK to true
   • Do you want a different bluetooth name? Change DEVICE_NAME
   • Do you want to mute/push-to-talk a different track than 1? Change CHANNEL_NR
   • Do you use a different PIN? Change BUTTON_PIN
4. Connect the ESP32 to your computer using the Micro-USB cable
5. Build & Flash the device using platformio

Usage

• Connect ESP32 to any power source (via MicroUSB cable, or your battery)
• Use bluetooth to connect your new mute-button

Usage macOS

• Open "Audio Midi Setup"
• Window -> Show MIDI Studio
• Click the Bluetooth Symbol

* A list of Bluetooth MIDI devices shows up. Select your device an click "Connect"

Don't forget to enable the MIDI Devices in Reaper and allow CC signals to be received. Enjoy!