Update: You can control and watch christmas lights yourself using Midi at http://heckenlights.org. Heckenlights are my publicly controllable christmas lights.

My basic idea was: Let start with something simple but expecting a great result. So I got and connected an ethernet-based relay (Did not have such a long USB cable) to a bunch of christmas lights and my Raspberry Pi. In the next step I created a controller programm and some midi files for having content. This together enabled me to control christmas lights synced to some christmas music. The control program maps the note on/off events to relay on/off events using the relay's output channels. Below you can see how it's connected.

See how it looks when all the components are connected and working

Carol of the Bells

Jingle Bells

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