It's not a matter of the driver operating quicker because the frequencies we're talking about are very slow. It's more that the 500 is not enough sub to cover the entire spectrum for your large room but if you narrow the bandwidth, the power appears to be more than adequate. I would expect the majority to cross over 80 Hz or below.

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