If im correct, i've read on the forums that a larger enclosure can make your sub hit lower notes. I've also heard some people say not to use the manufacturer's box specs for their sub, but to go larger if you want to hit those low frequencies.
Is this correct or are they wrong.
I ask because I went to my local audio shop hoping to get a larger box for my sub, but ended up not getting it because the "professional" told me that I should always stick to the manufacturers specs for the sub or the sub will not sound good.
A box will be made to a desired "tuning frequency" using the specs of the sub, which is why so many prefabs are a bad choice. You need to match the box's specs to the tuning frequency you're aiming for. The sub manufacturer will provide all applicable specs on the driver for the intended application. Simply placing a sub into an enclosure larger than intended will potentially harm it. Subs need the designed internal enclosure pressure to perform properly. Too big a box will cause excessive Xmax and eventual motor damage due to an almost free air environment.
Stick inside the manufacturer's specs for enclosure recommendations.