Not a fan of bass assist above 50hz..the maggies do well on bass color but hit problems in pedal tone octaves. One of the reasons I bought MG 1.7s was because as a tuba player I could hear they got the mid and upper bass right for timbre and articulation. Power wise with KT150s, the only time I hear clipping issues is when pedal tones and low fender bass are involved.
I also have Maggie 1.7s and have them mated to small subwoofers. In my case they are discontinued Mirage MM-8s, which have a long-throw 8" driver augmented by two long-throw passive radiators in a sealed cabinet. The active driver has a ver deep frame to allow the long excursion and a large magnet. The surround is a patented design that allows for long, well-controlled excursions. And the internal power is over 300w RMS (each), 1,200w peak. The diaphragms are all aluminum, so they are very light and stiff.
It doesn't offer a high pass crossover to the mains, but the continuously variable crossover can go as low as 50 Hz. I'd take it to 40Hz if I could. However, the sub controls also include a 0-360 deg. phase control. For awhile I was getting a hump around 80-100 Hz, which made little sense because the Maggies are so clean at that frequency and the subs' upper limit was set to 50 Hz. I figured there might be a phase problem. So I put on my mono copy of "Sgt. Pepper's" and cued up "A Little Help from my Friends." I chose that because Paul's bassline is very melodic and hops back and forth across that 50 Hz line. I listened to one channel at a time. Very quickly I was able to adjust the phase knob on one sub to make that hump disappear. Then I did it with the other channel. Since it was a mono signal it was little surprise that the phase setting on the second sub was the same. After that my subs and panels have sung as one.
These are the speakers for my LP-based stereo rig. Depending on the LP's mastering, sometimes the subs help a lot, e.g., if the bass is rolled off or the music is large scale orchestral pieces and big band. Other times the Maggie's sublime upper bass is all I need for small combo acoustic jazz.
Anyway, for your situation I recommend you have very fast, powerful subs with a continuous crossover and phase dial (not a toggle), and preferably a high pass crossover as well so you can roll off the bass signal to the Maggies to increase power handling.
