No idea about sound deadening capabilities but the live sound industry also uses the 19" rack standard so there are a bunch to choose from [1] if you want something non-traditional from a computing perspective. The roto-molded Gators were my personal favorite when I was trafficking a lot in rack systems... even more tangentially I really wish I'd help onto my ADA rig (MP-1, Quadraverb, Microtube 200) as now they're going for stupid amounts of money.