The length of the cables makes no difference for speakers or subwoofers. The cable could be 10 miles long, and the length of the cable still wouldn't matter at all (although the electrical resistance would matter for that extreme length of cable). The voltage signal travel through the cable at something like 80% of the speed of light in a vacuum, if I recall correctly, so the signal is traveling through the wire at approximately 240,000 km per second. Compare that to the speed of sound which is emitted from your speakers and subwoofers: 343 meters per second, which is much slower and will therefore make a far greater difference in the overall sound if they are emitted at different distances.
The short version is electrical signals travel too fast through cables to make an audible difference, but the distance from the speakers and subs to your ears might make a difference if they are too widely spaced. But in your case with the subwoofer only 2 feet away from the speakers, that is not going to make a difference.
