It's my understanding that these usually happen if you drop guitar suddenly or when in the case during shipping and it gets slung around or 'bumped' hard. While these two distinct design formats are used by a wide range of guitar manufacturers today, at the very midpoint of the previous century, they were distinguished as follows: Bolt-on neck guitars were made by Fender, and set-neck guitars were made by everyone else.You should be out of the woods. Putting a name on “everyone else” most prominently means Gibson, Gretsch, Epiphone, and a handful of more affordable Chicago manufacturers that had entered the electric guitar business by 1950.

That’s the year Leo Fender released the Broadcaster, which was not only the first mass-manufactured solidbody, but also the first with a bolt-on neck. Very generally speaking, a set neck transfers the resonance between neck and body more freely and immediately than does a bolt-on neck. The result is usually heard as a little more warmth and fullness in the set-neck guitar, and a little more snap and twang in the bolt-on guitar. The main reasons for these basic tonal differences are that the lesser, slower transference of acoustic energy from the non-glued neck yields a little more pop and attack from the string - in essence, it decouples the strings from the body and neck - whereas the more thorough transference of energy through the various parts of the set-neck guitar yields a thicker, juicier voice. The set neck’s tight coupling between all that resonant tonewood facilitates ripples of vibrational energy that round out, thicken, and slightly fuzz up the note, blurring it in a way that fattens the body of the note-all desirable if you’re going for a warm, resonant voice with girth and sustain.

On the other hand, the snap and pop of the bolt-on guitar emphasizes note definition, and a sharpness and firmness that contribute to a cutting tone. It’s what we often call “twang.” Although the slower transference of the bolt-neck guitar’s resonance might imply a slower response-and less detail in the tone-the opposite can often be heard.

For example, while the note’s body might develop more slowly, its attack jumps out from the instrument with less of the woody decoration more immediately apparent in the classic set-neck guitar. The thickness and warmth builds just behind the initial perception of the note, by which time that sharp, twangy attack has already made its mark.

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