Based on my 30 years experience of mixing FOH at a comfortable level for me that usually works out to be about 106 dba measured with a Radio Shack meter set to slow response time, I would guess that it was about 106 dbA JEEEZ. HE asked and I said I'm GUESSING....
....BUT, I made no claim other than it "sounded really good to me."
David,
You answered my question to the best of your abilities based on your observation of 6 Meyer JM-1 and two 700Hp subs at approximately 50 feet indoors producing around 106 dBA slow under humid conditions (about 10 dB louder than I find comfortable, but that is neither "hear" nor there).
Based on Meyer's claimed output level, a 106 dBA level at that distance with that array could be from 18 dB (or quite a bit more) under it's maximum level, the JM-1s would be loafing along at around 10 watts or less apiece.
I found the Meyers cabinets I commented about sounded fine at that level too.
Their HF just did not sound very good when driven anywhere near the rated SPL.
I'd chalk the reason they did not sound very good to HF diaphragm breakup and distortion, which are far more problematic in the low humidity conditions here, due to the added demands placed on HF drivers.
Thanks,
Art