I have no doubt she'll cave in
How's your treble performance with the 400s, extension, resolution et al? BTW, I admire your wife!
Compared to the DMA 360's and my DMA 180, the performance of the DMA 400's is literally like removing a piece of heavy cloth or foam from the front of the tweeter. There is so much more air, shimmer, and sparkle on the top end, and information in general, that was previously no existent, that it would be extremely hard to go back. The dynamics are also markedly better, along with the sense of exact image placement within the soundstage. The DMA 400's are truly special amplifiers that, in my opinion, advance the state of the art in solid state design. I have realized an even further "bump" up in performance running the amps through a Shunyata Cyclops. I may try a Typhon for the amps, but have not felt a compelling need to do this, so great was the Cyclops improvement. (while I have several dedicated 20 amp lines Spectral is extremely sensitive to any ground differentials, and I have found that the amps
in my installation, perform at their quietest on only one line).
Thank you for your admiration of my wife! She's also easy on the eyes! I hope that your wife eventually caves in. If she is into music she will be glad that she did! The notes will have so much more density and "meat on the bone" than your Martin Logans, you and your spouse's collective listening experience will only be intensified. (This is coming from a current Magnepan owner - on a secondary system, and former Quad owner.)
This is best summed up by a visit that I had the other day form a good friend who has not heard my current audio set ups. After listening to the Audio Research/Magnepan system in my workshop, we then listened to the Spectral/Magico system in the listening room. The first words out of his mouth were, "Oh my God"! 'Nuff said!
PS In viewing your sofa on the video that you had shared, you had better check your listening height, as your sofa' height appears to be somewhat too low. Alon Wolf designs all of his speakers with a tweeter situated 41 inches from the floor. He has told me for optimal listening you want to have your ears located between the midrange and tweeter drivers on the Q series. I am awaiting delivery of a Herman Miller "Goetz" sofa, which fits the bill perfectly. In fact, when I had ordered the sofa, I was told that these have been used many times before for audio listening applications. Deliver will be in about another month or so. I can't wait!
Additionally, with box speakers, you will probably need some room acoustic treatments to smooth out their frequency response, especially in the low end. In other words, there may be some additional expenses beyond the speakers themselves in order to optimize the performance of what they are capable of.