Carving both neck and headstock from a single piece of wood is wasteful and expensive, so many makers use a separate headstock, attached with a scarf or finger joint. The same is true for the outer edges of headstocks: the ‘ears’, which are often simply stuck on.
Angling the headstock back creates down pressure as the strings go across the nut, which is beneficial to vibration and sound. You may also see a volute on the rear, a small protrusion of wood that was originally there for strength at this weak juncture. These days, it’s more likely to be purely for aesthetics. Many acoustic headstocks will have a decorative wood overlay, often to match the fingerboard and bridge.
2. Nut (slot only shown)
“The nut can be made of various materials,” explains Eggle, “synthetic ivory, plastic, bone, Corian... It must be hard so it doesn’t wear through, and it shouldn’t bind the string when you’re tuning. The nut and the saddle material on an acoustic can greatly alter the tone; bone sounds very different from brass, from Tusq, and so on.”
As for nut widths, serious fingerstyle players tend to go for a ‘wide’ nut option (more than the relatively ‘standard’ 44.5mm/1.75 inches. Pure strummers tend to prefer something a little tighter.
There are no rules, especially as the neck back shape has a big effect on feel too.
Most acoustic ’boards are ebony or rosewood, though man-made materials such as Richlite are becoming more popular. Ebony ’boards accentuate the high- and low-end clarity of the tone (it’s a more dense wood) compared with rosewood. Ebony sounds ‘brighter’, generally.
Acoustic guitar fingerboard radii tend to be between 15 and 18 inches, much flatter than on most electric guitars.
Acoustic guitar frets tend to be a little thinner than those fitted to many electrics, because there’s less string bending going on.
5. Truss rod
The same as on an electric guitar, the truss rod is there to counteract the tension of the strings on the neck. The truss rod is usually adjustable from either the headstock end (underneath a truss rod cover), or through the soundhole.