Theoretically, there would be a timing difference in when the left and right signals actually reach the speakers. Whether this would make an audible difference or not, I can not say as the signals are both travelling so fast that your ears may not be able to detect the slight delay in one channel.
Regardless, I would go with equal lengths on the cables for at least 3 reasons that immediately come to mind: 1) You MAY be able to hear the timing diference, 2) Some manufacturers claim that their cables don't "work" in very short lengths. I tried to buy some 6ft MIT 750 cables once from a store and was told that MIT would not sell them in lengths of less than 8 ft. 3) Resale. It may be the furthest thing from your mind right now, but trust me, you are going to want to sell/trade these someday and will get zero interest/value if they are of unequal lengths.
Hope this helps.
Regardless, I would go with equal lengths on the cables for at least 3 reasons that immediately come to mind: 1) You MAY be able to hear the timing diference, 2) Some manufacturers claim that their cables don't "work" in very short lengths. I tried to buy some 6ft MIT 750 cables once from a store and was told that MIT would not sell them in lengths of less than 8 ft. 3) Resale. It may be the furthest thing from your mind right now, but trust me, you are going to want to sell/trade these someday and will get zero interest/value if they are of unequal lengths.
Hope this helps.