Ok. I getting the point now.
Just to ilustrate, let me show you some screenshot of my simulator program:
Lets get a music of example : Black Eyed Peas - The Time [The Dirty Bit] (Main)
If you get this music, and play it from 40 seconds to 80 seconds, you will ear some mid and high notes from 40secs to 60secs and from 60 to 80 secs, there bass notes.....
So I took this music and put into my simulator program, the Proteus from Labcenter Electronics and configured the audio input like this:
https://img.photobucket.com/albums/v222/ahhh/Eletronica/audio_in.png
I put the audio into my simple RC circuit:
https://img.photobucket.com/albums/v222/ahhh/circuit_LP.png
and got this:
https://img.photobucket.com/albums/v222/ahhh/Eletronica/out-1.jpg
The green one is the audio in and the red one is the out after the filter.
Look and you wil se that from 40 to 60 sec most of the audio is cut beacuse I have a lower-pass filter. From 60 to 80 most of the song pass beacause there is a lot of bass on that part.
The filter works, if on my original ciruit, above, I put the out signal into a trasistor base and on the collector I put a simple LED with a current limiting resistor, the led blinks only with the bass notes.
So I thought that if I put this "pulsing" signal from the collector into a 4017 this would be a clock.... but like I said, do not work very well....
PS: Sorry my english mistakes, not my mother language.
bye