I've uploaded the fourth draft of my crossover demonstration document. This publication includes first, second and third order networks as shown on the Pi Speakers schematic, and now the table of contents has been modified to include the updated pages.The most significant change is the addition of schematics for the various crossover and compensation networks. Schematics haven't been added yet for second and third order networks, but the Spice models for them are complete. All compensation networks schematics are shown, including RC dampers (Zobels), damping resonators (notch filters), resistor damped HF compensation and simple series attenuator HF compensation.
The models shown on this document and the Spice executables are available in the Spice models distribution on the Pi Speakers website. Also included are models for the third order networks used in Pi Speakers.