Originally Posted by DEMENTEch
Is there a big difference between the XS-12 and the XS-XXX ???.....
Sure. There's a big difference depending on the application. But you shouldn't select a woofer in isolation.
With a lower powered amplifier the XS-12 would actually have an advantage.
The XXX-12 will play much louder IF you have the additional power so not only is the extra power justified, it becomes essential.
The difference between the output of two woofers of equal size is the excursion. More excursion is the only way the same woofer can displace more air. If one woofer has to move the cone twice the distance and still under control this is major challenge and requires a very different type of build and demand for power.
You have to reconcile the woofer with your particular set of expectations & boat, and balance it with your specific system.