Not easily answered, it can be power and enclosure specific, as well as vehicle specific (they may be louder in a hatch or truck as oppossed to a trunk)
Are you looking to compete?
They are SQ subs , db reading is not crucial in the SQ comps
i was wondering i guess if it would be loud enough for my taste. i want the sq that the idq produces but i jus want to know if it will b loud enuf for me