[Frank[_8_]]

There is no new technology. I had the Bose 901 II with 9 -4.5 inch drivers
in a small
box, with a low frequency -3 db of 30 Hz. It was boosted +18 dB at 30 Hz.

The original 901 required a huge amount of power and it was new technology
and concept when it came out. There wasn't too many amps in its day that
could drive it loud. On the other hand, back in the 60s, there was
Electro-Voice 30" woofer that required very power to drive it, and when
coupled to the right box, it could blow a match out about five feet in front
of it.