Unbalanced audio on wallboxes - here is a cute little method of ensuring you have an equivalent unbalanced feed in a suite (for the inevitable VHS or DVD recorder) - Tony Dwarika figured out originally.

The rep coils (between the XLR panel mounts and the phonos) are from RS - part number 210-6419 and are mounted on double-sided pads. The coil has a high i/p impedance (typ. 10k) and so doesn't load the balanced signal but it ensures that the Avid (or whatever) is also available as an unbalanced feed - very neat when fitted in a Kelsey wallbox.