when you add more than one speaker you get an Exponential growth in SPL.
Disagree.
You are wrong,
When you Double the number of speakers - increase of +3 dB
this is what's considered to be Exponential Growth,
because it is also the same increase as Double amplifier wattage - increase of +3 dB so by adding an additional speaker qualifies as such an Exponential Growth.
Source for newbs:
http://www.globalrph.com/master_speaker.htm I feel I must point out that
you are wrong. The ear perceives loudness of sound, i.e. the acoustic energy transmitted by a sound pressure wave, in a
logarithmic fashion, not an exponential one. (Yes, there is a difference.) The
decibel scale is a logarithmic scale.
In case it's not clear, here are two charts for you. The first shows an exponential increase. The second shows a logarithmic increase.
Now that I have shown your understanding of a basic tenet of audio is flawed, how can any of us be sure the rest of your knowledge is sound?