What is a Truss Rod

The truss rod is an under-appreciated part of your guitar. This part is typically made out of steel and is hidden inside the neck of your guitar as an internal support. It is responsible for stabilizing the guitar neck and adjusting the action, which will be shown below.

Thaddeus McHugh of Gibson guitars first applied for a truss rod patent in 1921, although he was not the first person to think of this useful feature. Today, the truss rod is a standard feature of any guitar and is one of the primary parts musicians custom adjust on their instruments.

The truss rod is the primary factor in determining the "action" of a guitar. In other words, it is responsible for how close or far the strings sit above the fretboard, which in turn alters the way the guitar plays.

For instance, when the truss rod is loosened, the strings pull the neck and the resulting bend, if too extreme, can leave the strings dangling high above the fretboard and make them very difficult to play without thickly calloused fingers. Alternatively, by adding too much tension to the truss rod, the neck can feel stiff and the sounds become tin-like and brittle.

Ideally, you want enough tension on the truss rod so that the strings hover closely to the fretboard, but not close enough to produce a buzzing sound. When positioned correctly, the guitar is easy to play and produces strong, clear notes.

The use of truss rods has dramatically improved the quality of guitars while simultaneously reducing their price.

Never before have musicians been able to adjust their instruments with so much ease or effectiveness. This not only saves time and money, but allows individual customization for greater tonal control and a more personal action.

Thanks to this single shaft of metal, guitar companies are also able to use a wider variety of materials when constructing their instruments. In the past, because the strings exert so much tension over time, it was very difficult to design a guitar that could retain its shape over a number of years. However, with the advent of the truss rod, it is now possible to use a greater selection of woods and even synthetic materials, which reduce the manufacturing costs and offer a broader range of acoustic sound qualities.