Abstract: A folding marimba may include a first set of spaced apart rails; a first set of tone bars suspended from the first set of spaced apart rails; a second set of spaced apart rails; and a second set of tone bars suspended from the second set of spaced apart rails; wherein the first and second sets of spaced apart rails are configured for hinged rotation about a hinge line such that the marimba is configurable in an unfolded configuration having a first length and a folded configuration having a second length that is less than the first length. For example, the second length may be about half of the first length.

Abstract: A percussion instrument is adapted with a foam arrangement directly or indirectly in communication with its percussion surface. The foam arrangement reduces acoustic impact sounds when the instrument is struck, helps isolate vibrations from nearby percussion surfaces, and reduces or removes sound generation when air is released from the damper. To achieve these results, directly or indirectly secured to the percussion surface is an open-cell foam layer that is configured with a closed-cell foam layer positioned in a lateral side-by-side arrangement to create a spring and damper system. The open-cell foam may have one or more holes that extend entirely through its body, and inside those, one or more holes are closed-cell foam to provide additional spring-like functionality. The side-by-side dual-layer arrangement enables the closed- and open-cell foam layers to operate in tandem—the closed-cell layer operates as a spring, and the open-cell layer operates as a damper.