I've finally gotten all of the components off of the breadboard. I am now ready to stuff the whole circuit into an enclosure.

• The cable in the upper right is USB from the Arduino to a Macbook Air. The Macbook is providing power to the entire circuit and also running a node.js server. The cable in the upper left is audio output to a pair of basic computer speakers. The cable in the bottom left is going to the audio source (also happens to be the Macbook, but it can be anything). In my hand is the rotary encoder. Empty breadboard is there because it's stuck to my 'workbench.' Schematic and code to follow soon, I promise...