Is two Subs better than One?

Thanks for the info

Bob Reynolds, great paper just what I was looking for. The paper seamed to say that a fixed position 2 channel System does not have a problem like the multi channel multi seat position environment. Therefore, is it safe to say that one sub in the corner is as good as one in the center wall? Which position is better?
Or is two opposing center wall Subs still much much better?

Raul, wow! thanks for the info.

2 Subs Sound better to me. After all the opinions I thought I would buy a second DD15 Subwoofer. After setting it up but not yet finely tuning it; the volume needed to be decreased to synch with my Wilson 7's. I could definitely sense a fuller better balanced base. The mid and upper frequencies were more focused due to the fact that base appeared to fill the room better. With the base originally localized more to one side, the Wilson midrange on the opposite side did not feel as intergraded.
I guess bigger is better.

Lynhnn you split right and left out of Pre Amp into two pairs and run each pair to each Sub. Therefore the right Sub becomes the right channel and left, the left channel.
Each sub needs to be equalized separately. The DD series connects the master to the slave by a serial cable to control volume. Richard