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Just beautiful!

To the untrained eye, it looks like a mess. But to the highly trained EMC engineer, it is a work of art!

With regard to physics, you need box volume below 100 Hz. A sub can take care of that. The rest can be taken care of with multiple, motorized drivers 6.5" and smaller, aligned along the front, back, top and sides of a horizontally-oriented cabinet. And DSPs with room-adaptive algorithms. And amps for each driver.

House of the Rising Sone
Out in the mid or far field
Dedicated mid-woofers are over-rated