Every StoneAge cabinet is built using premium grade void-less Baltic Birch ply exclusively for it's strength, stability, durability, and it's superior tonal quality. This includes the shell, speaker baffle and all rear panels. Unlike many mass produced cabinets which can feature mediocre joinery, inferior build methods, standard wood glues etc, all StoneAge Cabinets are meticulously finger jointed by hand, then secured with a proprietary epoxy blend available exclusively for our cabinets. Rock-solid, roadworthy with overall clearer tonal definition at any volume. Est 2004, thank you for visiting.