In case you can't find the answer, you can eliminate the need to worry about it by running the 14-4 to both speakers with a loop at the first one. Slit the jacket at the first speaker at two points about 6" apart, pull the jacket to separate it, clip the appropriate wires for the first speaker at that point and pull them back to the first slit. Tape the slits. Done. Takes less time than running a second and dealing with the other BS.