This is some good reading here!
I'd like to share my first, but I really can't think of it clearly right now? I've had so many JBL pro speakers over the years. I did settled on crown amps for powering them. I believe I had an old set of used Altec 811 horns, with mid 2x12 cabs, and JBL bass "scoops" on the lows with maybe 2205s? on my first PA system. I kept building it up and went with 4560 cabs with D130s (later E130s?) for mids, 2440 drivers one the highs. The lows kept changing from the first big step of 4550 cabs on the lows, and later JBL double scoops on the lows. I'm guessing on some numbers as I just don't remember exactly.
I do remember setting up our system for our regular customer rental band called "Looker" in a large venue in Erie PA. They were the opening act and Uriah Heep was the headliners. I never heard our system cranked up so loud. We had 6 total 2440's on the highs with the 4550 and 4560 cabs for lows and mids. I actually stood behind the system as it hurt my ears out front. Their sound man must have been tone deaf from touring as the upper mids were just screaming. I watched over the amps and nothing was over driven. I had a partner Bob H. and he said not to worry so much that the guy was a pro.
That same system worked perfectly for years after. I never ran it that loud again. I was amazed at the volume level it was capable of.
Years later that first partner of mine went off to work for Clair Bros. and I went to a more intimate system for smaller clubs with the JBL bass scoops on the lows with a new partner Nick J. He left Spiro Gyra as their keyboard tech and we put together that new system. I took pride in making sure the system never hurt anyone's hearing and tried to get concert level sound with better clarity. We had upgraded to newer JBL stuff like the 2441 drivers at that time. We still had 4 of the single 15" 4560 cabs for mids and mainly 2206s? or 2226's? on the lows in the scoops. Worked perfectly for years with no failures at all!
I got to see some of the evolution of the JBL pro line and what Clair Bros. did for their systems. Their S4 cabs amazed the heck out of me on just how good they sounded. I remember hearing Asia at a Buffalo, NY theater and the sound was incredible. I still think of that as the best live sound I ever heard. I'm pretty sure that was Clair back then? Many years ago....