I was there and heard them!
The guy before me in the (test track) que was having crescendo music played.
But, I will tell you that the mid range capability of those JBLs was incredible!
I played my acapella neo doo wop test track on maybe a dozen speakers at the show and it was by far the best (second were the little red Lenehans and third the quads).
Effortless midrange that really separated out the four voices.
The sales guy liked that test track so much that he wanted to play it again.
It made the speakers sound so good!
Sad to say, very few of us have listening rooms that could fit them (not to mention wallets that could afford them).