Depending on where you live, you’ve likely seen a house with crazy flashing Christmas lights that change color and dance to music. Almost every neighborhood or town has “that one house” that goes all out for the holidays each year. In my neighborhood, that house is mine. If you’ve ever wondered how those displays work and what you need to make your own, this will be a short overview of all the components and how everything works together. There are three key things that make up a Christmas light show: the lights, the control circuitry, and the sequencing. The lights are arranged together to form different props like leaping arches, snowflakes, stars, megatrees, and more. You couple those lights with controllers and power supplies to make them work as expected. There is specialized computer software that tells the controllers when to turn on and off the lights according to the music being played. These components are at the heart of every light show and I’ll go into detail about each one. While you won’t be able to go to Walmart and pick this stuff up, there are many companies and a large, helpful community eager to help. About 5000 individual ...