Gradient Revolution Opinions

Your room is dictating the Pregnant bass hump.
if a speaker was accurate out of the factory for your room it would be broken in its design concept.

There is a company in bis for many years that can deal with this
particular issue but it's not for the simple or feeble-minded types.
 Research the Vandersteen Quatro CT Phase /Time  with analog Room compensation its
able to be adjusted even just a few inches out from the wall and perform far beyond expectations.
 Best JohnnyR

The Gradients excel at the realistic reproduction of bass frequencies even if they don't go ultra low.  The bass modules were developed as subwoofers for the Quad electrostatics and they possess that level of transparency.  The woofer modules do like power and I suspect the Lamms will be a good match.  The coaxial midrange/tweeter is coherent and very good at imaging, but there are smoother and more airy units available at a similar priced loudspeakers.  Unlike most loudspeakers the Gradients can also be setup for free field, near wall and I think even corner placement and still maintain its accurate bass qualities.  Additionally, if you want to take them to a higher level, an active crossover unit is available that allows you to use multiple bass modules per channel.  I used them from about five years with a high degree of satisfaction.

Here's some links to reviews:

http://www.regonaudio.com/Gradient%20Revolution%20Review.html

http://www.6moons.com/audioreviews/gradient/revolution.html

https://www.stereophile.com/floorloudspeakers/616/index.html

Good luck!

All I know is that when I had my Quad 63/Gradient Subwoofer combo (built for the Quads), it was the most seamless dynamic speaker/panel match I've ever heard, before or since.

The bass was almost as boxless as the Quad sound.  Though, it also lacked some of the kick/oomph of non-dipole subs.  But that aspect matched the same character of the Quads.

My room is almost the same size as the OP and I've been using the active Revolutions for the past 3 years.
Overall the best speakers I’ve ever owned.
See my system for further details.

We have the Gradient on display the Evidence.

The Graident is a very musical speaker howerver, it does not sound like a Magneplaner.

If you are looking for a set of speakers that will work in that room you should look at the Jantzsen ZA 2.1 which is a non diapole hybrid electrostatic. The sound is very open and they can work well in a small room they are adjustable for bass.

We would also recomend the Paradigm Persona 3F extremely holographic and detailed, fast like the Magneplaners, and they have good bass but will also work well in that size room.

We have them on display in a room nearly identical to yours. 18 by 14

Here is a picture of this sound room.Audio Doctor High End Audio Boutique - Photos
https://www.facebook.com/audiodoctor1/photos/a.122500301156525.22643.122499304489958/173841019956551...

In order to better guide you we would need to know your matching equipment and taste in music and of course budget.

Dave and Troy
Audio Doctor NJ