Table of Contents
- The Diagram: Anatomy of an Acoustic Guitar
- Parts of the Acoustic Guitar Explained
- The Neck
- The Body
- Final Thoughts
Check out the parts of a guitar diagram (larger version below) to learn the different parts of the acoustic guitar.
Below the diagram, there is a further explanation for each of the parts.
The Diagram: Anatomy of an Acoustic Guitar
Parts of the Acoustic Guitar Explained
O.k. now let’s look a little bit more in-depth into the individual parts of the acoustic guitar. Some of this will be a little bit technical for some or obvious for others.
The headstock is the very top of the guitar and houses the machine heads. This key component plays a crucial role in tuning, as it houses the tuning pegs or machine heads. Its primary function is to maintain string tension and alignment. The headstock’s design can vary significantly between guitar models, contributing to the instrument’s overall aesthetic and balance. Crafted typically from the same wood as the neck, the headstock affects the guitar’s durability and subtly influences its sound quality, demonstrating the intricate craftsmanship involved in acoustic guitar construction.
Machine Heads / Tuning Pegs (Tuners)
The machine heads are very important. They are the mechanisms that control the tensions of the strings. Part of the machine head is the tuning peg (or tuning knob).
The tuning peg, like the name suggests, is used to adjust the tension of the string to allow you to tune the string correctly. Does the tuning peg turn a cog that is connected to a ‘capstan’. The capstan is what holds the string in place.
There is a hole in the capstan that the string threads through and as the tuning peg are wound it turns the capstan via the gear and the string is wrapped around the capstan.
Loosening the machine head (by turning it to the left) will result in a lower-pitched sound. Tightening the machine head will cause the pitch of the string to go higher.
The design and quality of tuning pegs greatly influence the ease and stability of tuning. These acoustic guitar parts come in various types, including open gear and enclosed machine heads, each offering different levels of tuning accuracy and maintenance requirements. High-quality tuners hold the tuning longer and provide smoother operation, contributing significantly to the guitar’s overall playability and sound consistency.
The nut is located at the intersection of the headstock and the neck of the guitar. The nut allows the strings to be raised off the fretboard and also maintains correct string spacing – so it is a very important component!
The nut (along with the bridge saddle [a.k.a. bridge nut]) also controls how high above the fretboard the strings are. This is what is often referred to as the action of the guitar.
A lower action means that the strings are closer to the fretboard, and a higher action means that they are further away. A lower action can make the guitar easy to play, but if you go too low, you can end up with fret buzz.
Typically made from bone, plastic, or sometimes metal, the nut guides the strings, maintaining proper spacing and height as they transition to the tuning pegs. Its precise grooves dictate string alignment and play a significant role in the instrument’s action, affecting playability and comfort. The nut material and craftsmanship also influence the guitar’s tone and sustain, as it is one of the primary points where string vibrations are transferred to the guitar’s neck and body.
The neck of the guitar runs from the heel on the top of the body of the guitar up to the base of the headstock. The fretboard sits on the face of the neck. The neck connects the head stock and fretboard to the guitar body.
Necks are usually glued to the body on an acoustic guitar. Crafted primarily from wood, such as maple or mahogany, it supports the fretboard, strings, and tuners. The neck’s shape and size significantly impact the playability and comfort of the guitarist.
Steel-string acoustics and some nylon string acoustics have truss rods, which is a steel rod that runs through the middle of the neck to strengthen it. Most nylon strings don’t need this as Nylon strings don’t produce as much tension as steel strings.
This is why it’s a bad idea to put steel strings on a nylon string guitar. The neck’s construction, including the wood type and the neck joint, also subtly affects the guitar’s overall sound quality and resonance.
The Fretboard (a.k.a. Fingerboard)
The fretboard houses the frets (see below) and this is what your fingers press against when you are playing.
The fretboard is usually a separate piece of wood attached to the face of the neck and the most common wood used is rosewood.
The fretboard will often have spots or some kind of decoration, known as inlays, on the 5th, 7th & 12th & 15th frets (sometimes others and sometimes less) to help with orientation of where your fingers need to go on the fretboard.
The fretboard is inlaid with a series of metal frets, creating a grid that divides it into specific musical notes. These frets’ quality, smoothness, and spacing are crucial for ease of playing and intonation accuracy. The fretboard’s material and design contribute to the guitar’s tonal character, with denser woods providing richer, more resonant sounds.
Frets are pieces of metal embedded in the fretboard.
The frets control the tonality of the guitar. If you place your finger next to a fret it presses the string against that fret and essentially changes the length of the string that can vibrate, therefore changing its tone. Frets are small metal bars embedded across the fretboard at precise intervals, corresponding to musical notes. When a string is pressed down against a fret, it shortens the vibrating length of the string, producing a different pitch.
There is such thing as fretless guitars but these are by far the minority.
The body of the acoustic guitar is made up of the back, sides, and top. Often the top sheet (the soundboard) is made of a different wood than the back and sides.
The upper part of the body (closest to the neck) is known as the treble bout and the lower part is the bass bout. The waist (narrowest section in between the bouts) acts as a divider between the sections.
The shape of the body can have a distinct effect on the sound of the guitar.
The other factor that has a massive effect on the tone is the wood that the body is made of.
Many different kinds of wood are used in the construction of acoustic guitar ‘bodies’. What wood is used depends on the ultimate price of the instrument and the desired tonal qualities.
The two most common shapes of acoustic guitars are the dreadnought shape, the grand auditorium, and the classical shape. The shape of the diagram above is the dreadnought shape.
As you can see in the image below, the grand auditorium shape (left) and the classical guitar (right) have a more pronounced waist than the dreadnought shape.
The Sound Hole
The sound hole is not just to allow the sound to project but it is also very important for equalizing the air pressure to allow the soundboard to vibrate. Its primary function is to project and amplify the sound generated by the vibrating strings. The soundhole allows air to move in and out of the guitar’s body, which enhances the resonance and helps produce a richer and fuller sound. The soundhole’s size and shape can affect the guitar’s tone and volume, with larger holes generally producing a louder sound. Often surrounded by decorative rosettes, the soundhole also contributes to the guitar’s aesthetic appeal, showcasing the craftsmanship and artistic detail involved in guitar making.
The Pick Guard
Some, but not all, acoustic guitars have pickguards (a.k.a. scratch plates). These are, as they sound, to protect the soundboard from any damage potentially caused by a pick or fingers.
The pickguard is a practical and decorative element of an acoustic guitar, often found on the body below the soundhole. Its primary function is to protect the guitar’s finish from being scratched by picks or fingernails during play. Made from materials like plastic, tortoiseshell, or wood, pickguards vary in shape and design, contributing to the guitar’s overall aesthetic. While some players choose to remove or customize the pickguard for a unique look, its presence is essential for those who play more aggressively, ensuring the longevity and preservation of the guitar’s surface. Though a small detail, the pickguard reflects the guitar’s style and the musician’s personality.
At the southern end of the strings lies the bridge. The bridge is what holds the strings to the body of the guitar and transfers the sound from the vibrating strings into the soundboard. As the anchor point for strings at the lower bout, the bridge transfers vibrations into the soundboard for amplification. Its materials and construction methodology directly impact tone, sustain, and intonation. A well-crafted guitar bridge ensures optimal sound projection and contributes to the overall tonal characteristics of the guitar.
The Bridge Saddle (a.k.a. Bridge Nut)
The bridge saddle, in cooperation with the nut at the base of the headstock, controls the spacing of the strings and the action of the guitar (how high the strings sit above the fretboard). The bridge saddle also affects the tone depending on the material that it is made from.
Bridge pins are found only on steel-string acoustic, not on classical guitars (nylon strings). Do the bridge pins hold the strings in place in the bridge of the guitar.
The rosette is a distinctive and artistic feature of an acoustic guitar, encircling the soundhole. Traditionally, it serves both an aesthetic and functional purpose. The rosette’s intricate designs, which can range from simple patterns to elaborate inlays, add to the visual appeal of the guitar, showcasing the craftsmanship and artistic attention to detail. From a functional standpoint, the rosette reinforces the area around the soundhole, helping to prevent cracks and damage to the guitar’s top, which can be vulnerable due to the hole’s presence. The materials and complexity of the rosette vary, often reflecting the guitar’s quality and the luthier’s skill.
Bracing refers to the internal framework of an acoustic guitar, which is crucial for both structural integrity and sound shaping. Located beneath the soundboard, these wooden struts provide support against the tension of the strings and help distribute the vibrations caused by playing. The bracing pattern, typically crafted from spruce or cedar, is key in determining the guitar’s tone and resonance. Different bracing designs, like X-bracing or fan bracing, influence the balance between strength and flexibility, affecting the guitar’s volume, tone clarity, and responsiveness. The artistry in bracing design is a testament to the luthier’s skill, balancing structural support with the guitar’s acoustic properties.
The end pin, a small but essential component of an acoustic guitar, is located at the lower end of the guitar’s body. It serves a dual purpose: firstly, it anchors one end of the guitar strap, providing a secure point for the guitarist to hold and play the guitar while standing. Secondly, in many modern guitars, the end pin doubles as a jack for an acoustic-electric guitar, allowing the guitarist to connect the instrument to an amplifier or a PA system. Made from materials like plastic, metal, or wood, the end pin’s design can vary, often complementing the guitar’s overall aesthetic. Its proper installation and durability are important for the guitar’s functionality and safety during use.
Strap buttons are small but crucial hardware components on an acoustic guitar, designed to secure a guitar strap in place. Typically made of metal or sturdy plastic, they are located at the base of the guitar’s body and, depending on the guitar design, near the base of the neck or on the heel of the neck. These buttons enable the guitarist to attach a strap, facilitating comfortable and stable playing while standing. The secure attachment provided by the strap buttons is essential for the guitarist’s mobility and performance confidence, especially during live performances. Their robust construction ensures the guitar’s safety, preventing accidental drops and maintaining the instrument’s balance.
As the boundary between a guitar’s top and sides, purfling and binding serve both aesthetic and functional roles. Binding is a strip of material, often contrasting in color to the body, that runs along the guitar’s edges. It serves to protect the edges from minor impacts and contributes to the overall durability of the instrument. On the other hand, Purfling refers to the ornate, often intricate inlay that sits adjacent to the binding. It’s primarily decorative, adding aesthetic appeal and showcasing the luthier’s craftsmanship. Both purfling and binding play a role in the guitar’s structural integrity, helping to seal the joints between the top, back, and sides of the guitar body, and can affect its acoustic properties subtly.
The soundboard, or the top of an acoustic guitar, is one of the most influential components in determining the instrument’s sound quality. Typically made from tonewoods like spruce or cedar, the soundboard vibrates when the strings are played, acting as the primary amplifier of the sound produced. Its ability to resonate impacts the guitar’s volume, tone, and sustain. The soundboard’s thickness, bracing pattern, and choice of wood all play crucial roles in shaping the guitar’s acoustic characteristics. A well-crafted soundboard enhances the guitar’s tonal richness and clarity and contributes to its aesthetic beauty, often featuring decorative elements like rosettes around the soundhole.
Back and Sides
The back and sides of an acoustic guitar form the main body of the instrument, playing a significant role in shaping its sound. Typically crafted from the same type of wood for tonal consistency, they reflect and amplify the vibrations generated by the soundboard. The choice of wood greatly influences the guitar’s tonal characteristics; for example, mahogany provides a warm, rich tone, while rosewood offers a brighter, more resonant quality. The construction quality of the back and sides also impacts the guitar’s overall durability and resonance. The marriage of these components with the soundboard creates the unique sonic signature of each guitar, making the back and sides integral to the instrument’s acoustic identity.
Thanks for your time! I hope you now have a greater understanding of the parts and workings of an acoustic guitar. Next thing you will need to learn to read notes on a guitar diagram.
If you have any questions or comments please feel free to leave them in the comments section below and I will reply as soon as possible.
The major parts of an acoustic guitar are the head stock/peg head, the machine heads, the nut, the neck, the fret board, the sound hole, the sides and back of the body, the sound board, the bridge and bridge saddle, and the pick guard.
The 3 main parts of an acoustic guitar are the head stock, the body, and the neck.