It's possible to get excellent bass by using multiple smaller woofers as opposed to fewer larger ones. The surface area works out to be about the same but the smaller drivers are generally quicker.
For example, the bass specification of the Dali Megaline is 35 HZ.
That specification did not particularly astound me until I was face to face with the designer at the London audio show. When I found the measurement was taken at center line of an anechoic chamber I was impressed.
In a typical listening room the boundary reinforcement at the floor, sides and rear wall would improve those numbers substantially.
The Dali is a line source two way (ribbon plus woofers) with twenty four 6.5 inch bass drivers to achieve the desired surface area. They are rated in excess of 131 DB before breakup.
I will try to verify when mine get past the required 500 hours and I get some serious power on them.