Speaker Cable Length


I know that this thread has been visited before in gerneral terms, but I would appreciate feedback relative to my specific situation. My current speaker cables are 15 feet each. What, if any benefit, will result in using 10-12 feet lengths? What about 8 feet (the shortest I might be able to go after extensive re-arranging of equipment)? Thanks in advance.
jim
Thanks for the feedback, all. I've picked up a lot of information that I either wasn't aware of or hadn't thought about. At the end of the day I guess it still comes down to trying different cables. At least I have more to go on now. Thanks again.
Jim; thanks for the thread, I've got a similar situation to yours, ie 14 ft. Syn. Res. cables. But with rearranging I think I can get to 6-7 Ft, but I'll have to go to 4-5M ICs. Sam has a good point re: resale value. Thanks. Craig.
When I changed my 8' Harmonic Technology Pro-9 plus bi-wires to 12' there was not a noticeable difference. Perhaps a little less bass focus, but then I re-dialed my sub in, and there was no longer any difference whatsoever.