Bi-Wire or Double Run of Single Wire ???

I have a two pairs of single run speaker cables that I want to use in my Den system. I want to use both single pairs and Bi-Wire. Has anyone experimented with this?? My questions is: Is it better to re-terminate the two pairs together at the amplifier end, or is will there be no sonic difference if I just put the two sets of spades together in the binding post on the amplifier?? Thanks in advance!!!