Depending how amplified he is you'll probably want the UGLY turned up a bit more than you do for amplified rock music, BUT
The main thing to consider, though, is that (again depending how amplified it is) crowd noise such as applause may actually be louder than the music. Therefore, it is best to be conservative with your levels - if the music is peaking at -12dB or so, that probably gives you enough headroom to deal with loud clapping between songs. In post, you will need to hard limit, compress or otherwise reduce the clapping between songs, which can be a major PITA, but is kind of unavoidable in the situation you're describing.