How can I find out which tab sound is coming from?

There is an extension for Google Chrome that does this. It's called MuteTab.

Helps narrow down which tab that sound is coming from, browser-wide granular mute controls, automatically mute background tabs

I normally have numerous windows and tabs open and looking for a tab by the sound icon is a time consuming case of 'where is waldo'.

It's not a perfect solution but using the built in 'Task Manager' and sorting by 'Idle wakeups' column helps me find the culprit much quicker.