A proper setup is crucial to ensuring your guitar is comfortable to play, plays in tune, and sounds its best. It is good to know how to check the setup on your guitars even if you have the work done for you by a skilled professional.
It is important to know that there is no “perfect” setup; there must always be a compromise between ease of play and lack of buzzing. A guitar can be set up to avoid nearly all buzz, but it would be so uncomfortable to play as to be impractical. Due to different playing and strumming styles, and due to individual players’ left and right hand techniques, the best compromise between playability and lack of buzzing may be different. So, the “perfect” setup for you may be different than that of your friend.
Truss Rod
A truss rod is a metal rod or a combination of two rods or a rod in a casing that is embedded in the neck of a guitar to avoid excessive bowing of the neck woods on steel stringed guitars including acoustics and electrics.
Proper adjustment of the truss rod to control the amount of neck bow is crucial for a guitar to play comfortably and with correct intonation all the way up the neck. A well adjusted truss rod can also improve the guitar’s resonance by allowing the neck to vibrate in sympathy with the strings.
Classical guitars rarely use truss rods and do not need them due to the lower string tension of nylon strings and the more robust neck design.
The truss rod should be adjusted to its correct position before continuing on with the other setup variables. Although some guitar techs believe you need a special straight-edge to check the truss rod adjustment, many (if not most) top tier luthiers and techs recognize that guitars come with 6 straight-edges that can be used for this purpose – specifically, the guitar’s 6 strings.
You can check your truss rod for proper adjustment in the following way:
- With your left hand, fret the low E string 1st fret.
- With your right hand little finger fret the 14th fret (on an acoustic) or near the 15th to 17th fret on an electric.
- With your right hand thumb or index finger, press the string near the 8th or 9th fret and see how much the string moves before touching the fret.
A proper truss rod adjustment should have about a high E or B string’s thickness of space between the string and 8th or 9th frets. The check should be repeated on the high E string, because sometimes guitar necks develop compound bows. As well, if there is a discrepancy between the high E and low E neck bow, the inner strings should also be checked to ascertain whether the problem is due to lifting fret ends on one fingerboard edge, or whether the problem is indeed a twisted neck.
Given that most guitar necks are not twisted to a problematic degree, if the guitar neck has too much bow, then the truss rod should be tightened until the desired amount of bow is reached. If the guitar neck is too straight or over-bowed, the truss rod will require loosening until the desired bow is reached. Most truss rods will need only a quarter to a half turn for proper adjustment. Adjust bit by bit until the neck reaches the ideal bow.
Seasonal (dryness) conditions can affect the stiffness of the neck woods, so the guitar may need periodic truss rod adjustment to account for changing humidity. Taylor guitar necks, for example, seem particularly sensitive to seasonal humidity changes.
The Nut
The small piece of bone or plastic over which the strings pass to reach the headstock and tuners is called the nut. The nut has two significant functions – to space the strings to a comfortable spacing for the human hand, and to hold the strings at the correct height above the fingerboard.
The string spacing of the nut is not changeable after being set, but the depth of the nut slots is an important factor in controlling the intonation and comfort level of the guitar. When replacing the nut, the owner has the opportunity to change the string spacing if desired.
Present factory guitars are usually outfitted with pre-formed plastic nuts for expedience sake. Even the nearly ubiquitous “Tusq” is simply a brand name for a certain composition of plastic. Outside of purchasing a well-made hand crafted guitar, most factory made guitars (even “hand made” factory guitars) are shipped to the retailer without having had the nut slots adjusted to the proper depth. Reputable music stores will often do this nut adjustment for free with the purchase of a new guitar, but sometimes you need to request this work be done.
The nut slot depths can be checked in the following manner:
- Using right hand index finger, fret the guitar string on the wrong side of the 2nd fret.
- Now, with a free finger on the left hand, carefully fret the same string at the 1st fret.
- Watch from the side how much the string moves before touching the fret.
The high E string should have the thickness of only one or two pieces of regular paper between it and the 1st fret. The low E can have up to a business card’s thickness for people who play heavily on the bass side. (*When I worked with John LaRocque at Ring Music in Toronto, I was taught very quickly that the venerable Bruce Cockburn preferred his low E string and A string to be set higher than normal at the nut, otherwise he was not satisfied due to too much buzzing. Bruce plays fingerstyle with a strong right hand thumb, hence, this was his preferred setup.)
When nut slots are unduly high, fretting notes on lower frets can be painful and fatiguing, and also the string must be stretched greater when fretting notes, which can cause those fretted notes to be sharp in intonation. When nut slots are unduly low, open strings will create a bothersome buzz. Hence, setting up a nut properly is crucial to having a good sounding and easy playing guitar.
Saddle
The guitar’s saddle is the first transference point of vibrating string energy into the guitar top, or soundboard. A softer material will dampen (absorb) more vibrations than a stiff material, so plastic saddles usually don’t sound as good as bone saddles.
There are a few things to check with the saddle.
- Is it the correct thickness to fit smoothly but snugly into the saddle slot without binding (too thick) or rocking slightly from front to back (too thin). Also, it must fit properly lengthwise, a snug lengthwise fit is not as important as a snug front-to-back fit.
- The saddle bottom should be flat and parallel to the bottom face of the saddle slot.
- The saddle top should be shaped so there is a clear crest.
Neck Angle