They look like they were looking at someting on the scope…probably had an external controller.
I think it would be appropriate for them to tell us what amp that was they were running through. If anyone would tell us what would be an appropriate amp it would be the designers themselves.
Don’t know about the amp, (anything that’s rated from 20-20,000Hz would be sufficient for me, which describes almost any PA out there), but finding the right SPEAKER…that’s the toughie. Most 15" professional speaker cabinets go from 40-20,000Hz, but even the biggest and most expensive only go down to 30Hz.
If I could afford it, I’d buy it. But for now, my custom job will have to do. The 12" speaker I have will go down to 15 Hz at 90 dB at 1 meter on 40 watts…so that’s sufficient for me. I discovered the resonant frequency of wallboard with it.
I wish I could build one of these cabinets. I have the tools to cut the angles and the skill to build such a cabinet, but I don’t have the time required.