Interesting to see a band of their scale still shitting around between songs, during soundcheck, you know, the stuff that sound guys usually hate...
Oh, fun fact that no one in the comments seems to have picked up;
at 13m39s Kirk starts this riff of a Jaguar song; "Dutch Connection" (of course given that they were playing this show in the Netherlands).
Classic NWoBHM that's not that well known to some.