Bag End has been making Pro Sound reinforcement gear for over 20 years. I remember working with some of the gear
As to the design of their speaker and its' capabilities, they use what most would consider a backwards approach. They picked a large woofer ( to move a lot of air ) with a high resonance point ( so as not to interfere with LOW frequency reproduction ) and then equalize the driver for what should be a relatively flat and linear response below that point. This takes a LOT of power to do effectively, but then again, most woofers chew voltage and spit current anyhow.
As to a driver being capable of doing 8 Hz, that will have to do with the suspension of the driver and the tuning of the box. I have two commercially manufactured sets of speakers that will do 5 Hz. These make use of a box that would be considered a relatively small to medium sized floorstander. I would have never believed it if i didn't see / feel it for myself. I found this out when playing with a system "cleaning & calibration" disc. I guess that this is one of the reasons that these speakers have always been mentioned as having "powerful" bass, as they truly do go LOW. Sean
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