John,

Well, my measurements don't support your theory. When my VTF-3 was placed at a room corner, the room modes made a nice roller-coaster frequency response, with multiple >10dB humps/dips between 20-100Hz. With the sub relocated at the current position, the room modes have been quite well tamed, only with two 3-5dB humps at about 38Hz and 56Hz. These measurements are certainly corroborated by my listening assessments.

Anyway, where does that conspicuous number "~1.5 feet" come from?