Don't remember that ever being popular. Probably more talked about than done, much less accomplished successfully. That said, a friend biamped with Manley Snappers and a Coda System 100 on Dunlavy SCIII's with fairly good luck, although it wasn't all luck for a guy that builds his own DAC and preamp.
There was a time when low impedance, 12 and 15 inch woofers ruled the land and were inexpensive enough to tempt partnering with cheaper amplification.
There was a time when many big amps were clumsy.
That time was called "The 80's" and the world has evolved, except B&W ;). Not all for the better. Perhaps the 80's should best be remembered for life before HIV.
As I said, it can be done. I've done it and learned a lot. Even with MOSFET amps of similar character but different qualities and a xover at 90Hz, matching was difficult. Tried a decent pot on the bass amp but was constantly fiddling with different volume settings and recordings and it never did sound right. Custom made an attenuator (23 step, 2 to 4 Kohm, SE additive) and that was leaps better. How's your soldering?
I've evolved to Genesis 350's with factory servo bass amp/adjustable active low pass (avoids passive inductors). Added an active high pass (NHT X2, simple, fixed 12dB/octave) at 30 Hz higher than stock passive. Next step would be full DSP, 3-way active with real time analysis and removing the passive completely and intact.
