Does the brand's sub box rec. specs really matter, lets just say a brand says put their sub in a 3cuft box tuned to 38hz, what if you put that same sub in a 5cuft tuned to 32hz what will happen, if nothing bad will happen why do they even tell you the box specs?
because after company testing the rec box specs will yield the best transient response for a sq sub, and the most spl for a spl sub, and the best mix of both for a sql sub