The human hand is incredibly sensitive, so the exact shape and size of a guitar’s neck makes a huge difference to how the guitar feels, but the neck also has a substantial influence on the instrument’s tone and sustain.
So it doesn’t twist or warp, the hardest, densest woods are used to make necks: on electric guitars, it’s most commonly maple. Necks can be carved from a single piece of wood, or from several pieces joined together for added strength and rigidity.
Although primarily a playability issue, the shape of a neck also affects its overall mass, which has an effect on tone – more mass means a fatter, thicker tone. The profile of the neck can range from a somewhat flattened “D” through a rounded “D” to a distinct “V” shape.
Along with the design of the neck itself, the method of joining the neck to the body greatly affects the tone and character of an electric guitar.
Bolt-On Neck
This type of construction is the most common for electric guitars. The neck is simply bolted onto the body. This design is relatively easy to build, gives a clear, punchy tone, and is easily repaired if a guitar is damaged.
Set-In Neck
The neck is glued into a groove or slot on the body. This method of building a guitar is slower and harder, so is more expensive. This design offers a more pronounced mid-range and bass. A damaged neck or headstock can be repaired, but it’s quite difficult.
Neck-Through-Body
This type of neck extends from the headstock through the end of the body. Each side of the body is glued to an opposite side of the neck, like wings attached to an airplane fuselage. It’s the hardest and most expensive type of electric guitar construction.
Neck through body construction creates an extremely strong instrument capable of excellent sustain with a deep, thick sound. Replacing a damaged neck is impossible. Combined with the cost, this makes neck through body electric guitars relatively rare.