Q: I'd love to hear the actual recording of how it sounded
A: Check this video
Q: But what about sync issues?
A: The drummers were REALLY solid, which helped A LOT. Also, we had a couple of big lights clicking along with the metronome.
Q: Are there really 1000 rock musicians in this part of italy who all like Foo Fighters enough to learn the song, move other plans for the day and travel along with their equipment to this place to do this?
A: Not from that single part of Italy! There used to be a page with names of all the participants and their hometown, I can't find it anymore. Anyways, I was there, I can tell you people came from all over Italy. I guess we're passionate people and we like ambitious and original projects! Also, I'm sure the organizers did a great job advertising, I actually found out about it through one of those random Facebook ads, which is nuts in itself, who would have thought?!
Q: What about the group on the stage in the middle - were they hooked up directly? Were they special in some way?
A: The group in the middle were so called 'Gurus', professional musicians hired by the organizer to serve as 'reference' for each type of musician. They recorded demos and put out advices on the website for us participants.
Q: Honest question though, wouldn't the speed of sound cause a bit of an issue?
A: Well, all I can say is that it worked well. I guess the fact we had LED lights clicking like metronomes + really solid and tight drummers (which for example, us guitarists could still hear properly even though amps were fairly loud) + a great conductor sealed the deal.
Q: They must have done a fair amount of post production to get this video.
A: We also recorded multiple takes, I think six in total. Post production of course is a given, surely it's something to be done.
Q: Did they audition people?
A: There was a selection process. We were asked to send a video showing we can play our instrument.
Q: Where you were standing, was there just a/an plug/extension cord on the ground for you to use?
A: Yes, we had multiple power strips all over the place
https://www.reddit.com/r/videos/comments/3f5hj0/1000_musicians_play_learn_to_fly_by_foo_fighters/