Here's a few from a rather dimly-lit concert a while back, when I was still using my K-5. My dad was the first owner of this lens; it came with his M-X back in the day. These were all taken with the aperture wide open.
Reason why I brought the M and not the F version of this lens (which I use more often) is that I prefer the focusing ring of the M for manual focusing; especially useful when doing video (below). I rarely do this type of photography anymore, so the lens doesn't get much use, but still, it's a nice piece of kit.