Modding in colours or colormusic in your computer.

  The scheme of colormusic.
  The colormusic scheme is very easy. I thought it up in an hour and in a second hour I finished it on a bread board.
I set the level of input signal by variable resistor. I took the signal from speakers. Not to make a fault of sound card amplifier output, desolder only one lead! It’s important. The switch turns on the diodes without sound.
  Maybe somebody will do better or do it without this feature. The make is easy and if you have details you could do it for two hours. I indicated transistor pinout scheme for beginners.
 

  Normally soldered scheme should work at once. The only thing you need to do is to capture R* resistance. On the scheme I indicated nominal for turning on one diode. Four lights would shine very dim with such resistor. On my computer four lights shone bright with 820 ohm resistor. I recommend you to make experiments before filling in the diodes with resin.