Creating a Custom Fader Box
UCSB MAT 5940, Sensors and Interfaces for Media Art (Winter, 2010)

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My primary method of setting the loudness of individual notes in my music is based on taking a set of reference points of size 2n+1, where n is a positive integer; generally, I find 17 reference points suffices in most works. I used to use a WxWidgets interface in C++ and number spinners to set these reference points; while using these tools, it became clear that it would be much more convenient to use something much more traditional - a fader box. The trouble was, that few fader boxes had 17 faders - if they did it might have been 16 plus 1 master fader. I thought this might be distracting while composing, and so I undertook the construction of my own custom fader box. The parts I used were:

- 1 custom aluminum panel from Front Panel Express (actually includes 20 faders: SPAN, CNTR and MISC were included as well)
- 1 Arduino board (Diecimila,
- 1 MUX Shield (multiplexer with 48 analog i/o,
- 1 aluminum housing (Mouser Electronics Stock Number: 563-AC-433)
- 4 5/16 inch screws with bolts
- strips of terminal pins (for connection to MUX shield, soldered to ribbon cable)
- ribbon cable 26 gauge stranded (.67 meters, containing at least 22 wires)
- black and red solid wire (24 gauge)
- 20 10k Ohm faders (data sheet)
- 20 fader knobs (data sheet)
- 40 nylon screw spacers (McMaster-Carr Part Number: 94639A207)
- 40 machine screws (McMaster-Carr Part Number: 95836A211)
- 60 .187 inch 16-14 female disconnect terminals (

The picture above shows the assembly of the faders on the panel. The spacers were used between the back of the panel and the faders.

Here is another picture of the wiring.

Solder this better than I did.

If you ever plan on taking the Arduino out again, do not glue it in as I did, mount it properly with screws.

USB provides power for this fader box. Total cost was around $270. This is the code I used to send serial data from the arduino: fader_box_mux.pde.