I agree with bdp24 the best cabinet is none, others can include Bent and Formed Laminations, I have seen fabricated steel used, Celestion used Aerolam , an aluminium honeycombed laminated material. Cast concrete is fun and not to mention an easy favourite , Lead Lined . The sand filled cavity has been used in the UK for transmission line cabinets for years, I love this hobby, all roads can lead to Rome.
