Subwoofers for Magnepan 20.1s?

1. In my experience, I believe the JL subs would work fine. I'd go for the 10 or 13 inch models and use two.

2. JL Audios built in software for room equalization works great and makes it easier to blend the subs with Maggies.

3. Plan on purchasing a seperate external crossover like a Bryston or equivalent. I'd find one so you can rid yourself of the Maggie passive crossovers and use the electronic crossover to work with your Maggies and subwoofers.

4. I've tried blending without using an exteranl crossover before, and while you can indeed improve your sound, you won't really get the ultimate performance without an external crossover.

Have fun!

Steven

My guess is that further extention may not be what you're really after -
unless you're a pipe organ guy. If you're down 6db below 33 hz, that's gonna
be inaudible on most recordings. There's a coupla keys on the piano that
MIGHT be slightly diminished, but they're not struck often.

However, that "little dip" in the 50-60hz range is right at the
point where the impact of a kick drum is established. You can certainly place
subs or EQ subs independently of your mains to get more energy in this range
- but you'd need to actively cross from your Maggies at a frequency north of
there, maybe 65-90 hz. A Velodyne SMS-1 sub-controller or SVS
"Audyssey box" (plus an active crossover like the NHT x-2) will
allow for EQing the problem.

The JLs (12" or higher) definitely show more beep bass extention than
the MJs or (almost any of)the RELs on tests. They are also show
"tight/fast" respone (group delay), but not quite as well as MJ or
REL and they are expensive. I chose Rythmik Audio 12" subs which look
like REL/MJ in terms of group delay, but offer better extention.

These observations are based on test results at AVTalk.com (seems to be dark
now) and HTShack.com - not on listening experience, so take that FWIW.

Good Luck,

Marty

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