I wanted this subwoofer specifically since the unit is compact and uses a passive radiator. I had expectations that this sub would just be something to complete the low frequencies and not be anything loud. It definitely surpassed my expectations, this sub bumps! It’s not crazy loud, but for the compact size of this unit and for the amount of power it takes, it moves a lot of air (it’s louder than I expected, it shakes the rearview mirror quite a bit). Since it is a passive radiator, it sounds like a ported enclosure (which I prefer) and hits the low frequencies very well. I am very happy with my purchase, perfect for my application since I did not want to take up much trunk space. I would recommend this to someone who wants a subwoofer for a great value, wants it to be easily removable, and not take up all their trunk space.