I have searched for this and found some solutions for Analyser bars here:
This tutorial is old and you need to remove webkit prefixes to get it work.
I could make it work with local mp3 files. But for Icecast streams it's not working because
source = context.createMediaElementSource(audio);
should be changed to something
source = context.createMediaStreamSource(stream);
but how to vreate stream object from icecast url like this:
Thanks in advance