Is Bass Non-Directional In A Two-Channel Rig?

You can hear where the bass originates even below 40 hz. Again the box/enclosure is a giant passive upward frequency generator. A 40 hz crossover point will not stop the box from being pressurized above that selected frequency. You will increase the sound stage image size by roughly thirty percent with the proper implementation of time aligned stereo subs. Ground the subs to the floor
Tom

Mitch4t,
Sorry, I just realized that I did not completely answer your question... Also yes, you can put a sub behind you. Back at Marcof Electronics seems like 300 years ago, we had our own sub design. We buit an 8, 10, 12 & 15 inch model.. At some time or another we had tried each of these sitting right behind us, Maybe 2 feet, while the speakers were about 8 feet in front of us. Once spl was matched, they all worked well, undetectable.

"Again the box/enclosure is a giant passive upward frequency generator."

Only if the design/construction is incompetent.

Kal

I still find this research pertinent and it will answer some of your questions.

http://www.harman.com/EN-US/OurCompany/Technologyleadership/Documents/White%20Papers/multsubs.pdf

Kal

A room an enclosure and free air are all passive radiators so they all must be incompetent. Tom