electromechanical specs, or 'thiele/small' parameters. things like vas, qts, qtc, fs, etc that werent mentioned in the manual. but dont worry bout em mate. just keep it in your current box and enjoy.

tho theres one thing you shouldve learned by now after your vibe, jl & now a philips sub: buy once, buy right. with all the money you spent on em, you couldve just got 1 great sub in the first place instead of replacing em with mediocre ones. oh well