I wonder which would be better, a passive crossover with Auricaps and large pure copper air-core coils or an active analog crossover with generic electrolytics and low-cost op-amps. Or a digital crossover with ADCs and DACs. With active crossovers, you have the benefits of reduced bandwidth in each amp but there is added complexity in the system overall. A digital crossover can easily set delay for any channel, a definite plus for people running basshorns. Lots of variables to consider.

On a similar note, I've been using Keith Larson's new WTPro/ST system which uses DSP to create filters from Spice files. It's like having a Spice parser that sets up an active crossover for testing. It's a great tool for crossover design work!