Real curious about what sub you have.
Years ago, my first sub, was nothing but boom. It was a low price Yamaha.
Next sub was a Definitive Technology prosub 1000. It was better, but still had a little boom to it. In hindsight, I figure it was intended to serve in HT.
Got tired of playing that game and went to a REL 10" sub and found nirvana. Properly set up, a good sub is hard to notice, except for a little more depth and better definition of low frequencies.