Well, my SVS SB1000 subwoofer is quite a low end boombox type sub(I was tricked with SVS marketing) when I add a correction the bass gets significantly worse. I blamed Audiolense at first, then when adding correction to a normal sub I found regardless of the roll off you essentially get "how you correct it" or the bass extension or time domian correction you play with. The results are great, time alignemnt is superb but on the SVS it renders it significantly worse.
With the SVS sub no matter how you roll it off even a winkle of a correction renders the sub like boombox. Now, I am hazarding a guess that the plate amp already has some DSP which bumps up the frequency towards the lower end and artificallly attempting to flatten that perhaps causes it to get even boomier, I dont know. I am not an expert but there must be a reason why this happens. I have had some experts on forums swear that a sub regardless of size with the same roll off is hard to distinguish from one another of course if parameters are similar, and I do agree transients are better with a natural sealed roll off compared to when adding a correction but again this is specualtive at best. My point is why does the SVS get worse when giving it a full sealed type roll off and riding it with its lowest extension? In theory it should get a little more transient, unless the thoery is totally off.
Anyway I digress. For some reason the SVS sub unfotunately can't get better with correction it actually gets significatnly worse so I would like to leave the sub and correct what is above my sub crossover point.