An SVS 16-46 PC+ in the right front corner; an "antique" M&K 15" passive in the rear left. (These are actually directly in front and back of my seating area, which is on a diagonal).
Experts would generally advise against this, but it works for me.
The arrangement flattens out my room response significantly. Not perfect, but measured +/- 4dB from 16Hz to 100Hz, meter compensated. (It sounds smoother, as the highest adjusted readings are below 25Hz, where ear sensitivity drops off. Measurement peaked at 18 Hz.)
No EQ on the SVS, but I use an ART 351 equalizer on the M&K, which is driven by a 200 watt AudioSource amp. I measured 108 dB SPL at my seating area on WotW, at -10 on the receiver. Room is 2200 cu. ft. including adjoining kitchen.