I had to revamp how I was listening to my masters because, to my embarrassment, I had sent some of my work out to public with the bass all messed up (unknown to me). This occurred even though I had done what you're supposed to do, listen to them on as many different systems as possible. I had done that, listening on a portable mp3 player with ear buds, and three other consumer systems with speakers. Still, to my dismay I had no real idea what was going on with the bass below 100 Hz on some of my material and it came back to embarrass me. The lesson learned was Tannoy 501 Reveals don't "reveal" below 100 Hz. They are excellent otherwise. For low frequencies one simply can't compromise on what's a "laws of physics" thing (big cones are much more efficient for low frequencies) so I'm already lying to myself if I think small, relatively inexpensive, speakers are going to sound out accurate bass. I already knew that, but it took a bit of embarrassment to get me to realize my own system wasn't giving me the reference I needed. Knowing a subwoofer was the least expensive way to resolve my reference monitor issues, this PreSonus subwoofer fit the price I wanted to pay, and appeared to offer the most for the money so I bought it. Based purely on the laws of physics, a three speaker system (a stereo pair for higher frequencies plus a mono sub) can more efficiently sound more accurate than a far more expensive full range stereo pair that doesn't have a subwoofer. In that case, the total cost for the three speaker system would be much lower than an equally "accurate" stereo pair. It all depends on the design of the speakers, but again, based on physics the three speaker system wins out price wise for efficiency. As for this PreSonus subwoofer, I like it when things arrive and really do have as much quality as the sales literature indicates, and I don't have to return it. I set the crossover to 100 Hz and turned the gain up just enough to hear the bass and feel it just slightly, which put the control at about the 1/4 position or about half unity. I have otherwise not bothered to spend any time calibrating it because my "studio" room isn't even worth the effort to try to calibrate, it's totally not a studio. This setting of the sub for me is likely to solve things because I was getting over driven bass on some of my former mastering work and now when I turn down the bass in the mix, I believe I'm more correctly compensating. The important thing is to hear the bass at the mixing / mastering sitting position, which now I can hear (and feel a bit), but couldn't on anything else I've played my material on. I like that I can plug power for this subwoofer into the same power strip as the Tannoy's and flip all three on at once (by flipping the switch on the power strip), no added pops from the power spike through any of the speakers, it's a clean power up. As for PreSonus, this is my first purchase of any of their products. I'm impressed with the high quality of this subwoofer monitor. Nicely done.