Will try harder to keep the explanations more basic. The RPi3 thing is really just a fun use for the little computer.
Lets try this description and see if it is clear on the amp front for the speakers.
Normally to drive a segmented line array, the drivers have to be connected as series/parallel combinations to make an impedance that stock amplifiers can drive. When two drivers are connected in series, the sensitivity of the pair is the same as one driver with increased power handling capability. When two drivers are connected in parallel, the sensitivity goes up by 6dB for the pair. This is at the expense of the impedance now being 1/2 the original value.
If I were to take 8 - BG Neo10 planars and put them all in parallel, the sensitivity would go up by 18dB if they are all well matched drivers. In real life, it will be less than that due to differences. The problem is the new impedance for the amp to drive is 1.33 Ohms. Not something most amplifiers like to see as a load.
Now if each BG Neo10 that has a 6 Ohm impedance has it's own amplifier, then the sensitivity increase is the theoretical 18dB increase at the expense of 8 amps. With today's solid state Class AB amps, that is not a great expense and can have great sound quality. The amps only have to be capable of driving one driver to full potential, not the entire array. Instead of one 600w rms amp capable of 1.33 Ohm load drive, you have 8 - 75watt rms amps driving 6 ohm loads. That is the approach I am using.