Seems from that list that there are hardly any that make it to 20hz. Just like the full-range speakers with woofers I was talking about.
"All figures are for a corner loaded subwoofer, measured at a 2 meters using 10% thd limits in a large 7500 cu-ft room.
The SPL numbers have been averaged from the maximum output(with a 10% thd limit) using 25,32,40,50,62hz steps
in testing(the 25-62hz range is considered the bass intensive film range)."
those were not manufactures specs, just for that room