Rod Smallwood, who has managed Iron Maiden since 1979, has been talking to Radio Futuro in Chile about what the band have just finished.
Europe's stadiums last year, the festivals this summer, then America, and now South America, with between thirty and sixty five thousand people a night. If you do not like playing to that, he says, you might as well give up.
The detail worth keeping is about where he stands. He normally watches from the mixing desk, but in a stadium the desk is boxed in with a roof and sides against the weather and he cannot see the crowd from it, so in South America he goes up into the stands or the boxes instead.
He watches the audience rather than the band, in other words, and he has a reason for it. The Chilean crowd has a rhythm and a flow he says he has not found anywhere else, and that is why En Vivo! was recorded there in 2012.
Forty seven years of this and the man is still choosing his seat by where the singing sounds best.