So, is it a vented enclosure with corner room loading, or what? In an old speaker book, theres a corner horn, with a slot going the entire height of it about 1inch wide. a very simple triangle box.

Pi seems pretty good, loud and pure sound.

I have a 1/4wave reducing airpath with 12inch on end, (driver Fs=45,Q=0.15!(measured Q!),vas=6cu ft) SO it gives quiet bass. almost non-resonant, with wool (t-line) its the quietest sub youve ever heard (and smoothest) for 10$ of wood.

When i have the space,i think i want a Pi.