I found a decent enough 75x75 resized microphone silhouette after what Kirn said.
Here is the original:
and here it is once I resized it to 75x75:
It's kind of needs work around some of the edges, but I think it's as best as we might find in terms of a "chorus" badge if we want to make it feel as so. I don't know, I only know basic photo editing, but I think this is good enough.
You may have already tried it though with the search on microphones, but ever since Kirn mentioned silhouettes, I thought I'll just google that as well. There a number of possibilites to work on as well for this one.