Even though a planar diaphragm is physically larger than a typical cone woofer, its excursion capability is much more limited in speakers like the Magnepans. Typical cone woofers can move an inch or two to produce their sound while planars are limited to a small fraction of an inch...
So by design, unless you have a planar with huge woofer area, conventional cone woofers work better for bass extension and power.
So by design, unless you have a planar with huge woofer area, conventional cone woofers work better for bass extension and power.