Biamping, bass and amplifier type.

Quality standmount speakers plus quality tube preamp/amp and quality sub float my boat.

I used to have a pair of Wilson Cubs (60Hz to 25kHz)on sand filled Sound Anchor stands driven by a 110 wpc Sonic Frontiers tube amp and matching tube hybrid pre. Frequencies below 60Hz handled by the original model Sunfire True Sub. The sound was to die for @ a relatively modest price of $18,000.

One night the amp caught fire (probably my fault for not dusting the tubes frequently enough). While the amp was being repaired, I replaced it with a SS B&K 200wpc amp. The sound degraded by about 30% (like everywhere: clarity, soundstage, speed, you name it).

IMHO, bi-amping should only be done w/ monos designed for that purpose. So that's like 4 amps! One would have to be immune from the Recession to do that.

I'd rather go with a true full range towers (like down below 30Hz)and either SS or tube 2 channel amp or something like my Cub/Sonic Frontiers system.

Best results and most flexibility comes from single driver set-up. In other words, a separate amplifier channel connected directly to each driver. This means you cannot use a passive crossover. Your signal proceeds from preamp to active crossover and on to each amplifier. I believe this is the real definition of bi-amping and the only way to truly benefit from doing so.

Excellent.
I really want to thank you all for your excellent, well written, well thought out responses.
Because of you I am really enjoying my renewed interest in audio.