When the sound wavelength becomes less than the diameter of the driver (1kc for a 12" driver), the driver becomes directional am I correct?, as the driver goes into 'breakup' where diffrent parts of the cone radiate the sound wave both radially and coaxially, becoming more concentrated towards the voice coil as freq increases.
So if you have a number of smaller diameter drivers in a cab then your power rating goes up but your directionality remains reasonable, multiple small drivers seems the norm for speech cabs used in bingo halls and the like.
I can appreciate side lobes being introduced from the location of the drivers and the differences due to tolerances and phase changes caused by time delays.
Is there something I'm missing, its been 15 years since I had anything to do with the sound business.