This sub is a big step down from Monolith line. Which makes sense because of the price. The reason for low rating is because there are much better alternatives in this price range. The sub does work though just doesn't sound that great. I'm using in a spare room so not that big of a deal but I should've just spent a little more for a competitor.

When I first decided to purchase a subwoofer, some 6 months prior to the purchase. I realized the unfortunate fact that my options of visiting an actual brick & mortar store to hear the sub were limited. So, after many hours in front of a screen reviewing the hundreds of choices I had, I did infact decide on the Monoprice SW12 400 watt model # 41498. Thank God. I have been thrilled w/my selection. It has the power to shake the floor on my movies and the tightness to bring my music to life. The appearance fit with my other components well and the size was not as bad as I was lead to believe. I will point out the reviews from Wirecutter among others are what pushed me over the fence. Count me in as a big fan of the Monoprice SW12 400 watt slice of heaven. Just wish I would have decided earlier. Phil

Great room shaking sound at a super price!!!

Clean punchy solid bass you feel! Adds impactful low end to movies and music. Great Price! Great Sub! Stop thinking, get it!! Will make you smile...again and again.

This was recommended by the NY Times. I'd not heard of Monoprice before. I bought the SW-12 to upgrade an older stereo 2.0 Bose system that had a non-powered subwoofer.
As my Sony amplifier had only "speakers out" (no dedicated sub or audio out), I tried that first. The SW-12 manual indicated that choice was the least desirable, and it was correct: performance of the SW-12 was mediocre. But I subtracted 1 star for that.
So I then got a new Onyko amp with dedicated subwoofer output. A huge difference! Really deep, feel-it-in-the-chair bass. But bass distribution throughout this large room was not uniform. I needed to move it about 20' to the back corner.
But hardwiring was a problem. So I got the DYNASTY WSA-5TR bluetooth for subwoofer device. Wow it's very good with no perceptible latency. So now I have the original Bose non-powered sub in the front of the room, the SW-12 in the back, and uniform bass throughout the room.
Now if only all my music was equally balanced!

I purchased two SW-12. If I compare them with my old subwoofer (a Sony), I can very confidently say that SW-12 is a superior sub. No distortion, very clear and powerful. It does not go down to 10 Hz (I do not care, and it is unnecessary), but above 25 Hz, it is excellent. I connected them to Pioneer Andrew Jones floor speakers. Pure joy.... Also, the shipment was fast, plus, when you call monoprice, you talk to a real person :-)

Larger than I expected but I found a place for it. Not the easiest to set up with a new receiver/tuner but once my son got it set up the sound has been great and what I expected.

No complaints. Paid $150 for it. For the price, you can't beat it.

1st thing is I purchase two of them. Wow!! what a great balance POP to my existing old 2005 system. This subwoofer has to be dial into whatever system you have, and results are great sounding subwoofer. No don't just buy one of these bad boys.. Buy two as a set. trust me you will not regret it at all. I used Anti-Vibration Isolator Pads Heavy Duty Blue EVA Pads to raise them even higher off the floor. If the port is pointed towards the floor, raising the sub. will give it even a greater effect. This sub is one bad Sub. Even better then Polk audio psw505 which are twice and a half more expensive.

I?m not an audiophile but usually have a rather expensive taste when it comes to audio equipment. I bought this subwoofer only as a temp solution because I actually want to buy an expensive DSP-Controlled woofer. But I desperately want it in white and that?s hard to get. Now that this woofer is so good I?m wondering if I should just stick with it and repaint it. No idea how they can sell it at this price point without going bankrupt.