So Max SPL is not a single number, but an average of all those SPL numbers from 10Hz-200Hz?
That really depends on the marketing department.
Take a good look at the figures. Is it 128 db or 111 db? Most companies do not post the numbers we did. Some do and I applaud them.
We posted a decade span from 10 to 100 hertz. There is a serious drop in the output. But most peoples rooms will have serious reflection reinforcement along the same lines as the drop. So thinking of the room as adding in a mirror image in the way of refection to the out put. Tis sub, and most other subs to some degree can give you quite a flat frequency response in room.
Where this sub has quite an advantage in in swept volume, and very low distortion. So much more dynamic, a sense of limitless power.
Simply put this is one very good subwoofer capable of very high sound pressure levels. And due to the low distortion levels it is very tuneful, as in you can discern the changes in pitch away down low. Very important to me. I have loved organ music for 30 years, and there are all kinds of rumbles grunts and thunders away down low that few loudspeaker systems reproduce. I have quite a large collection of classical music and I regularly review recordings. Subs like this bring many things you never heard before to light.
When I was listening to this sub before we tested it I kept telling Nathan that this is the closest thing to a proper large format horn I have ever heard. I have been a specialist in high efficiency horns for many years. This gives you most of what they do in a much smaller package. And the dynamic range is quite interesting to listen to believe me!