I've never seen a beginner's guide to designing active speakers. I wonder if it exists. Everything I've seen online is vague hand-waving about using standard crossover shapes, with no mention of baffle step, driver EQ etc.
Ofc, in the end, there is a lot in common with passive design...
As I spent more time with active, I realized that a hybrid approach is a good compromise. One key difference is the design flexibility you get with an active crossover. While some of the sim tools are great, I really enjoying active crossover prototyping as you can quickly measure and listen to a potential design modification. Also, with active, there is less need to waste power padding down the higher frequency drivers. Baffle step is a shared issue, but active gain allows the designer to approach compensation differently. The main challenge with active is all the wiring - the hybrid approach helps reduce wiring and protects tweeters better too.
If someone does not get there first, I plan to document an active Directiva design. One challenge is the flexibility. I may make several changes per hour while designing a crossover. This will need to be approached as a more disciplined overall process than I tend to do currently.
The minidsp application notes offer an approach, but is very basic. Am sure a more experienced designer (not me) would be better able to articulate.