The neck on the left has the standard 5-piece construction used by Guild since the late 1950s. The neck on the right was used from 1977-79 that has a 5-piece construction similar to that made by Gibson where the stringers are set wide apart. It's not known why Guild chose to use this style maple neck on some archtop models (CE-100, X-175, Starfire), but not others (X-500, Artist Award). Perhaps it was simply an experiment to make a better neck or to make a 5-piece neck more easily. Or maybe it was a construction technique necessary to create a stable neck based on the quality of maple that was in their wood inventory at the time.