Martin D-28 Authentic 1937 Acoustic Guitar Perhaps the most revered vintage D-28s are the ones created in 1937 with forward-shifted hand-scalloped X-bracing, an Adirondack spruce top, and a 1 3/4 neck width. This model is an updated version made with Guatemalan rosewood back and sides, and it includes some subtle spec refinements to make it even more faithful to the original. One of the major updates is a more accurate body profile based on dreadnoughts from the 1930s and 40s. Martin’s VINTAGE TONE SYSTEM (VTS) is employed to age the top and braces, which captures the tone from the 1930s era. Martin’s craftspeople can recreate the pleasing visual aesthetics of a vintage guitar and reproduce the particular tones previously reserved for vintage instruments.