sdecker et al, it is important to keep the cap values consistent with the original design. Judging by your description, the 1uF bypass caps were left in place and the main caps replaced with SAs, thus keeping the total paralleled capacitance correct. Regarding outboard crossovers, tread lightly. The crossover network works in an environment of the woofer magnetic field and the close proximity between various crossover inductors as well as vibration. When finalizing a model, some values were sometimes slightly tweeked to adjust for that in-cabinet environment compared to the open-air development environment. Sharing our experiences will help in learning this subtle landscape without the resources of a full development lab.
I am hot-rodding my PowerPoint 1.2s for studio monitors and must outboard the crossovers due to insufficient interior cabinet volume for the larger upgrade parts. I expect performance improvements from the combination of outboard mounting, greater proximity isolation (increased footprint), lack of woofer EM field and vibrations, point to point wiring, six nines hookup and choke wire . . . in addition to the higher-performance caps. Note, my PowerPoints are late-date manufacture from China. Although care was taken to spec first-rate parts, I can't know if the Chinese manufacturer used parts as sophisticated as Thiel in-house manufacture did. I am upgrading with all original-Thiel parts and techniques. I will journal my results by comparing an unmodified pair with the modified pair in the same system.
