Here is a kit that lets you visualize your music and put on a light show. The Musixel Kit can be attached to your audio devices to convert the frequencies into colors. It has LEDs with 9 different color modes. The Musixel mixes colors when it detects multiple frequencies.
The kit is pre-soldered and easy to set up. It comes with a 16 LED strip with wires, audio cables, audio splitter, and other parts you need to get started. You can find out more here.