Section View - One of the easiest methods for dampening resonance in housing material is adding mass. This design has two chambers, creating a double-walled enclosure. The speaker driver is installed, and shipped to the end user, who customizes their enclosure by adding a material of their choice. Sand, or even concrete could be used to fill the enclosure. Keeping the product light weight until it reaches the end user saves shipping costs, reduces fuel use, and allows the user to utilize local materials.