MixeryPi C

A hardware Mixer based on the Raspberry Pi to control the Behringer X-Air 18

Features

• Control your Behringer X-Air 18 Wire hardware buttons and rotary encoders
• 8 buttons to choose channel
• button to switch layers so you can choose from channel 1-8 or 9-16
• button to mute all channels
• rotary encoder to choose output (Main, 6 AUX-Busses) Push button to toggle fine-mode (control even more precisely)
• rotary encoder to increase/lower a channel's volume. Push button to mute channel
• WiFi and/or ethernet connection possible
• 2x16 LCD

Required components

• Raspberry Pi (I used a 3 B+ )
• 2x16 LCD (HD44780)
• 10 pushbuttons
• 2x rotary encoder (KY-040)
• Resistors:
  • 10x 2k Ohm
  • 4x 5k Ohm
  • 1x 10k Ohm potentiometer
• 4x 100nF capacitors
• Micro USB and ethernet mountable extension cables
• Some kind of housing
• Flat cable
• Screws and spacers
• 2x potentiometer knobs

Tools

• Pliers
• Soldering iron
• Drill
• box cutter
• file

Installation

• Install Raspbian
• Maybe you have to install WiringPi
• Download all files from this Repository
• Connect to your X-Air 18 via WiFi (or to an external router that your X-Air is connected to)
• Enable SSH on the Pi for future updates and maintenance (HowTo)
• cd to the path where you saved this repository
• cd into the directory "build". If it does not exist yet, type mkdir build and press enter.
• type cmake .. && make in the console and press enter
• ignore the warning
• to autostart the program:
  • cd to /etc/ and open rc.local : sudo nano rc.local
  • add the path to the programm, for example: home/pi/MixeryPi/build/MixeryPi &
  • don't forget the &-symbol. Click here for further information.
• Wire up the hardware as shown in this and in this table:

GPIO-Pin	Connected to
4	LCD RS
17	LCD E
18	LCD DATA4
22	LCD DATA5
23	LCD DATA6
24	LCD DATA7
26	Button Channel 1
21	Button Channel 2
20	Button Channel 3
16	Button Channel 4
12	Button Channel 5
7	Button Channel 6
8	Button Channel 7
25	Button Channel 8
19	Button Toggle Layer
13	Button Mute All Channels
9	Button Toggle Fine mode
6	Button Toggle Mute Channel
5	Volume knob CLK
11	Volume knob DT
10	Choose output knob CLK
27	Choose output knob DT

You can choose different GPIO-pins, but make sure to change them in the define-section in the main.c-file.

Future updates

There is a lot of refactoring needed. I also want to add some more features step by step and maybe some day I can control each and every parameter with this gadget.

Next I want to add:

• controlling the FX-Channels
• controlling each parameter of the EQ for each channel. Maybe I'll get rid of the fine-mode in the future and make that button some kind of Shift-button which triggers different modes when pressed together with others buttons.