Acoustic resonators are formed by injection molding or other process that allows the shape, size, orientation, and arrangement of each resonator to be customized. Customizing the features of the resonators allows their resonance frequency to be adjusted based on their intended deployment. A non-periodic or non-uniform arrangement of the resonators can increase the level of noise reduction compared to a periodic or uniform arrangement of the resonators. A chain guard includes a recess to receive a chain that supports a plurality of resonator rows or frames. In the stowed configuration, the chain guard pivots towards the row/frame to more compactly stow a panel of resonators.