Musical painting

Hi folks-

At the moment I am producing visuals for a band tour and I want to be able to paint/draw a picture using the sounds that the band makes. A bit like an etch-a-sketch but powered by the bass, mids and high tones. Any help would be greatly appreciated.

Cheers

retro machine with the points added by sound?
I think thats where I would start, where you end up is something else!

check out the FFT node to analyse audio.
Study & understand Tonfilms Beat detection module and the grrrid girlpower demo.