Ayone know the wattage used at a Rock concert?

Powered, likely class D, phased array or line array systems are pretty much the standard now. 1,000 or more watts per speaker (more for subs) so simply count 'em up. Note that the primary feature of the famous huge Dead system wasn't just midrange drivers, it was the fact that each musician was using their own discreet pile of PA speakers within the system, instead of the normal thing of everything mixed together.  This resulted in basically a complete, discreet system for each instrument...a logistic nightmare, but according to a friend who heard one of those shows, you could hear a clear Dead song from blocks away from the venue.

I could (and sometimes did) hook my trust A7s to my KLH Model 20 (the one without the tuner) compact system that had a mighty 24 watts or so per side, and it sounded great. For years we used a biamp thing made by Kustom (a non tuck and roll item) that had 200 watts for the bass bins and 100 for the horns…worked great and certainly shredded some ear balls.

In the late 60s it was fashionable to use a pile of Altec A7s driven by whatever…Altec amps maybe, Macs…and the sound was friendly and sort of warm. (My bands in the early 70s to mid 80s dragged a pair of A7s around, albeit with heavy duty bass drivers). A corner was turned in the 70s to things like JBL loaded boxes from Tycobrahe and Clair Brothers with maybe Phase Linear amps, and the new normal was REAL LOUD and somewhat less warm and friendly. I'm currently a live sound mixer for smallish shows (jazz and folkie stuff mostly) and use both powered and passive speakers that sound modern and clear, careful application of powered 18s for subs, etc., and can actually get a warmish sound…but I do miss the A7 days.