I don't know if this would work in the British folk clubs, but—

I knew a fellow back in the 1960s, an unemployed actor, who used to frequent the coffeehouse where I was the "house singer." Alex was a bit of an egomaniac, and he used to give my a great deal of unwanted advice on my performances, particularly what he thought I was doing wrong. Among other things, it was my duty as a performer to keep his interest engaged. It didn't seem to matter to him that the rest of the audience was thoroughly engaged;   I had to keep his interest. The main problem with that was that Alex was primarily interested in himself.

One evening when I was in the middle of a set, which was generally going well, I could hear Alex's stage voice booming out of the back of the place as he talked loudly to a couple of people he had brought with him. People turned and glared at him, some shushing him, but he continued to run his loud mouth—of course thoroughly embarrassing his table companions. By doing this, his message to me was that I had failed to engage his interest.

After he had talked loudly through the better part of two songs, when I finished my current song (getting a particularly enthusiastic ovation from the rest of the audience, letting me know that, whoever the bullhorn in the back corner was, they were with me), I was totally fed up and decided to take direct action.

Although the place didn't really need a PA system, there was one there, and it was turned on, giving just a slight boost to my voice and guitar. Normally I sang about two feet back from the mic. After the applause died away, I leaned in very close to the mic and said, loudly,

"ALEX!"

My voice, coming out of several speakers around the place, sounded like the Voice of God. Surprised at my suddenly very loud voice coming at him from all directions, Alex's head jerked up and he looked at me. Having got his attention, I delivered my message.

"ALEX, SHUT THE HELL UP!!!"

The rest of the audience burst into applause!

Alex got up and left. I haven't seen him since.

I'm not exactly heartbroken about that, though.

Don Firth