One handy box that forms a crucial (if unglamorous) part of io 0.0.1 beta++ contains the audio preamp (basically, a couple of filters, signal amplifiers and a balanced line driver) and power supply/distribution components (9V, ±12V). I don’t have a name for this box yet, but here are the layouts for the front and rear panels.

Front panel (click to see SVG image)

Rear panel (click to see SVG image)

The enclosure I am using is the Hammond RMCS9018 half-width, 1U rackmount enclosure [see PDF drawing].