Magnepan 20.7 and Subs

As the OP, I have to say first of all that I listen to pretty much only classical music. OK, a bit of jazz here and there. I find the bass on the 20.7’s not only adequate but PERFECT really. I think my original idea to supplement them with subs comes from the fact that I CAN (financially anyway), and also from the fact of my never ending need to "improve" things. So I’ve pretty much decided not to invest in a pair of subs because I'm rather convinced that I would simply be creating more "problems" to solve.  There are folks in this thread who really know more about what they’re talking than other folks but its up to you dear reader to DISCERN that. Just remember, more experience = better advice. @jafant The only other development is that ODDLY, I have gone back to the Aesthetix Atlas as my amp of choice with the Maggies at the moment. I’ve gone back and forth between the Atlas and the Pass X150.8 (also thinking that perhaps I should move up in the pass line to a more powerful amp). But the Pass product is SIGNIFICANTLY warmer in the midbass. The Atlas is incredibly airy, perhaps a very slight TINY smidgen "clinical" but still very very good. I did think about attenuating the midrange panel using a resistor on the 20.7s with the Pass to see what that would do and I may still experiment with that. There’s absolutely no doubt that the Pass did WONDERFUL things for my Thiel 2.4s but I don’t like it anywhere near as much with the Magnepan 20.7s, MUCH preferring the Aesthetix Atlas as my amp at the moment.

@pwhinson, if cost is no object, and your 20.7’s give you enough output in the bottom octave (20-40Hz), look into the Eminent Technology TRW-17 Rotary Woofer. IAR’s Peter Moncrieff has characterized the TRW-17 as the world’s only true "subwoofer", as it is designed to reproduce only 20Hz DOWN! It provides substantial output all the way down to 1Hz, possible because it is not a woofer (whether cone, planar, horn, or any other traditional driver) pushing air, but a rotary fan. It’s a fascinating design (and it’s creator Bruce Thigpen a very clever and creative fellow), so head over to the ET website to read all about it.

I'm a newbie Maggie 20.7 owner as I just received a pre-owned pair in excellent condition. The SQ and feeling that the artists are in the room with you is unbelievable.  I would like to trial the use of a sub to allow the sub to handle frequencies at about 50Hz and below.  With all the positive remarks about Rel subs, is there a way to connect the Rel so that it limits the frequencies to the Maggies to 50Hz and above or is a crossover needed for this? 

I apologize if this is a common question answered in several places.