Problem
It is not easy to run audio visualizations for music playing from websites. Sites such as Pandora.com, YouTube.com and Vimeo.com do not have built in visualizers for music.
Are you not sure what a visualizer does or is? Check out this link to Barry Martin's Hopalong Orbits Visualizer it is actually interactive with your mouse or with touch if you are on mobile.
Are you not sure what a visualizer does or is? Check out this link to Barry Martin's Hopalong Orbits Visualizer it is actually interactive with your mouse or with touch if you are on mobile.
Workaround
If you are like me you open one window with a random visualizer such as by searching YouTube for a video that is recorded this way. Checkout this link to see what I mean by these videos. I always start the video and mute it. Then I open another window with music playing. The major and obvious downside here is that the visualizations do not match up with the music playing.
Close but no cigar
There are a couple of close options I have found but they do not do exactly what I am asking for here. One I found was APEXvj which allows you to search for songs or to use your microphone as a source for the audio input. As far as I can tell though it does not let you pull music directly from a webpage or another tab.
Solution
I think someone needs to write a Chrome Extension that you can add-on to Chrome. It will then listen to audio feeds from open windows and with one click allow you to start a visualizer of that audio source.