So recently I've been pondering about how to separate out the layers of a song to control different led's,kinda like a VUmeter.I wanted to separate out the Lead bass,rhythm bass and the melody.So I've designed a circuit which does this,It's only in it's primitive design stages,and I have not tested it out yet,but in theory it all works,the circuit would also allow you to connect a subwoofer as well.I wanted to make this possible without a PIC.
EDIT: I forgot to turn off transparency,so right click it and select "view image" and you'll be able to see it.
Here it is: