I'm with Al it should not matter enough to worry about. As some have mentioned wire geometry can have a small effect - especially placing wires far far apart (best place them close together). Twisting wires is most important for small signals into high impedances or for signals lines passing through very noisy RM/RF environments - I should not think it matters for speaker cables.
However, solid core versus stranded is probably not enough to worry about either (other than teh stiffness may cause connection integrity problems at each end). So I guess this makes a full circle - it must all be critical!! ;-)
However, solid core versus stranded is probably not enough to worry about either (other than teh stiffness may cause connection integrity problems at each end). So I guess this makes a full circle - it must all be critical!! ;-)