Best viewed in "landscape" mode.
While this is far from a deep repository of information of the speakers built by the various incarnations of Advent Corporation, I will include the information I do have in case it is of interest to anyone out there.
So far this is what I have to offer:
Upgrading a pair of Advent Prodigy Towers with a custom HUMAN 81 Kit.
7 Kelsey Road, Lee, New Hampshire 03861