When I saw the Gyroid Infill I was enthusiastic. It could be used as infill for a closed speaker box. It would work as an enforcement and acoustic foam in one. All I would need to draw would be the outer shape of the speaker without an inner surface. I would need would design a hollow hemisphere behind the driver. Finally I would need to remove the shell on this hemisphere.
The infill would provide a very stiff speaker and a suppression of air resonances within the cabinet.