Modifying a speaker by changing its crossover components is something 99% of us cannot do; such changes transform the sound into something distinct, and one can only hope the modifications yield a satisfactory result. The video showcasing their work suggests a suboptimal listening room: one speaker is next to a large bookshelf, the other in a more open area, the front wall is cluttered with equipment and a large screen, and the seating area is similarly arranged. Assessing the impact of the modifications in that room, it seems they would be unique to that setting, even for the stock speaker. Nonetheless, they appear to be enthusiasts who take pleasure in their hobby, which is commendable. My own foray into modifications taught me expensive lessons about resale—there's virtually no market—and sound quality. The equipment sounded more balanced and accurate before I replaced parts with costlier ones, which altered the entire voicing of the system. A designer once told me that you construct a circuit based on the components used. Inserting parts that emit more high frequency than intended shifts the sound towards the high end, resulting in excessive brightness. Nelson Pass and others possess more experience than any hobbyist, but if they enjoy their work and it brings them joy, that's what truly matters. They noted cabinet vibrations, but all musical instruments vibrate.