The one on the left has a Mahogany body and the one on the right has a Maple body; so my guess is that the one on the left is a little warmer, and the one on the right has more attack and more high end support. Also, I can't recall seeing much discussion on this but it seems to me that because a five string has a more massive neck that a four string, that there may be a difference there as well, perhaps showing up here as a bit more sustain, and maybe even a touch more fundamental support, for the five string.