Subwoofers for Magnepan 20.1s?

I own a version of these with my hybrid stats. They do as advertised. They were specifically designed with Magneplanars in mind. Give Duke a call or email at audiokinesis.com. He'll give you more facts. Also, a friend of mine has the full tilt Planetarium system (bipolar). Pretty awesome.

"The main obstacles to natural-sounding bass reproduction are the inevitable room interactions - which impose large peaks and dips on the bass response. By using multiple subs spread asymmetrically around the room, each sub will produce a unique peak-and-dip pattern at the listening position. The combined average of these unique peak-and-dip patterns is much smoother than any one of them would be, resulting in more natural-sounding bass with excellent pitch definition. The Planetarium bass system also avoids the subjective slowness of most subwoofer systems by taking room gain into account. Typical in-room extension is to 20 Hz, but the main advantage of this approach is bass quality, not quantity."

Powderdocter, take a look at my review here on the GON regarding why I now have a pair of Martin Logan Depth i's sitting behind my biamped MG-20's. You will be amazed at what the right Subwoofers will do to the soundstage depth/width, layering in the soundstage, and "ease" of your 20.1's, not forgetting the extension on the bottom end. I just want to share if you don't have your MG-20.1's on Myesound stands you have not heard their true potential sonicly.

I recently voiced a pair of Martin Logan CLXs with the M-L Descent i subs.

They were smooth, went deep, were lively and dynamic, and blended almost seamlessly with the CLXs.

From that experience, I'd suggest that the Descents would go nicely with the Maggies.

Of course, you need two of any sub for the best sound, so I'm referring to a system with two, most definitely NOT one.

See relevant comments beginning at post 190 in this thread:

http://www.martinloganowners.com/forum/showthread.php?t=7730&page=13

Very few subs will mate with the 20.1. My advice is to try one of the JL Audio subs. The ported bass of the Rel makes it sound a little sluggish in tandem with the 20.1. In my experience, only a sealed sub has any hope of keeping up with the bass panel.

Dukes Swarm is a good design. Martin Logan Descents work well,but you will need at least 2. Also KSC has a 31.5in driver in custom bass system which was designed with large loudspeakers like maggies in mind. Low excursion bass systems have far better transient responce over large excurtion floor corner reinforced subwoofer systems with all there many comprimises in design. The large driver only moves slightly so less detail is lost than hi-excurtion designs. Lots of detail in low bass most never experance this since they use conventional sub designs.