Sub mates up good to my Defiance X12. Break it in and let it breathe. I find the only oddity is the infinite gain knob on the back vs the remote. Tech told me knob had no stops, as I was setting it up I found that odd. But sub is fantastic.

I like it a lot. Great upgrade from the 8" Sony I had since high school.

Have a Speedwoofer 12S connected to a Sennheiser Ambeo Plus soundbar. With the sub volume at 45-50%, it’s all you need to rattle dishes in the kitchen. This sub has exceeded all expectations and keeps on delivering. I am thoroughly satisfied. Shout out to Joe Rodgers on helping with a technical issue with another brand soundbar that wouldn’t work with the 12S. (Pic is the sub with a cover my daughter fabricated and a cat-mat to keep those annoying fur balls from resting on it).

The pair Speedwoofer 12s I got sound and measure great. Measured in room response is flat to 20 Hz. It's exactly what I wanted and totally meets my expectations.

For an improvement: please round or chamfer the top edges that run from front to back, since the woofers aren't very handsome. Aesthetically, they need something simple done to them to make them more attractive.

My 8 year old Polk Audio 12in sub died, and I wanted to step up my 7.1 system. I found RSL via google search, then youtube reviews that were all glowing at the cost / performance.

I decided to purchase the 12s and 3 CG23M's for all my fronts. With a couple calls to RSL support to help out a noob; running Audyssey a couple times on my Denon. I cannot believe how much sound I was missing, the advice on where to place this 12s from Joe and crew was the icing on the cake. I have large 20 x 33ish theatre room in the basement and this thing rocks it all, with great placement to the side of the room via wireless kit.