Edit. Add this preamble to OP.

I used WinISD and its 416-8B database parameters to come up with upper and lower ballpark tuning options for my cabs.
1. Optimally flat: -3dB @ 35Hz.
2. Extended bass: -8dB @ 25Hz.

However WinISD does not take into account the corner position room gain that will affect my speakers. I took this gain to be ~+12dB.
http://www.harmanaudio.com/all_about...kers_rooms.pdf

I mentioned that I could use EQ. and that I thought a higher tuning would give better transient response.

I ran this past GM and he suggested that I post it here for all to see.