A length difference of 186 miles will result in a .001 second delay between one speaker an the other.
A millisecond delay is audible - but the several nanoseconds you would get from a reasonable length difference will be far from audible.
I suppose someone could claim capacitance difference between the cables, but as long as you're using decent cable (12 ga. zip cord) I won't believe anyone who claims to hear a difference.
Any difference heard would be due to the capacitance in their head - not the cables.
