Littlebits are so darned expensive. The idea is cool. They look and feel good. They are fun to play with, but not at all sure about the value for money side. The W11 / W12 transmitter & receiver modules do not pass through audio, but they do allow buttons and sliders to operate remotely located output bits. One transmitter and one receiver will allow 3 functions to operate over a range of 100' or so. A single transmitter can control multiple receivers, but all receiver channels follow the one transmitter. You can't use multiple transmitters in the same location.This is revised in the W21/W22 (I think) modules being released around Dec 2015 and included in the Gizmos and Gadgets kit, where you can select one of 5 channels, allowing multiple transmitters to be used.Interestingly, the radio module on the W11/12 bits has a mode that allows very flexible pairing between multiple radio modules. this requires running the radio module in mode 3 rather than the mode 2 that littlebits opted for. Not an easy hack sue to the surface mounted radio module.