Putting music signal into the Analog Input of an Arduino can be pretty boring. That is, unless you use a totally awesome chip like the MSGEQ7. This simple Spectrum Analyzer driven with an Arduino only takes a handful of parts. I used these incredibly awesome protoboards from Adafruit for the first time. The protoboard alone gives a fit and finish even before it starts!
Mixed Signal Integration has a cool little chip that has 7 built-in bandpass filters. Run an audio signal through it and you have an instant audio spectrum analyzer! This is a simple spectrum analyzer based on an Arduino. Each of the 5 LEDs represent a single section of the chip’s 7 sections of audio spectrum.