The first thing anybody notices in a church is the reverb, and the first thing an engineer notices is that it is not the same in any two places in the room.

Where the microphones go

Too close and you lose the building, which is the reason you came. Too far and the attack of every note arrives softened, which in fast music is fatal.

A church does not have an acoustic. It has several, and they are three metres apart.

I start eight metres back and two and a half metres up, and I move from there. Half the time the answer is to go higher rather than closer.

What goes wrong

• Heating that nobody can turn off, humming at fifty cycles.
• Chairs, which move and creak, and matter more than anything electrical.
• The hour, because bells and traffic keep their own timetable.

Why it is worth it

Because the room does work that no amount of processing will do afterwards, and because the musicians play differently in a space that answers them.