Anatomy of An Acoustic Guitar – Parts Explained

Last Updated on November 22, 2023 by Teemu Suomala

At first glance, the mystical workings of the acoustic guitar can seem overwhelming. If you’ve ever found yourself looking online for acoustic guitars and thought, “What in the world am I looking at?! or What Does New Bracing-Method Mean?!” you’re not alone. 

Today, we’re going to take a deep dive into the anatomy of acoustic guitar and unravel its great mysteries. Continue reading as we explore all of the inner workings of this six-stringed wonder. 

Learn about electric guitar anatomy here.

Parts of Acoustic Guitar – Diagram

Measure Points of An Acoustic Guitar

Parts of Acoustic Guitar Explained

The acoustic guitar -— one of the most versatile instruments around, from writing folky, emotional ballads to serenading friends around a campfire. But are you aware of what each part of the acoustic guitar is for? 

Let’s break it down!

Headstock

You can think of the headstock as the unsung hero of the acoustic guitar. It is a major part of the instrument that holds all of the tuning pegs in line, which are there to keep the guitar in perfect pitch. Without a headstock, well, you wouldn’t have a guitar. 

Different guitar manufacturers often have unique headstocks to differentiate them from one another, though there is also plenty of overlap. One of the most popular headstock designs found on acoustic guitars is the 3+3 style. This design features three tuning pegs on each side of the headstock.

The 3 + 3 headstock is different than the six-in-line headstock style, which you’ll often find on Fender guitars, though rarely on acoustics (except for Fender Acoustic Guitars and Fender’s Acoustasonic(which we’re not sure totally counts)).

There are some slight advantages and disadvantages to certain headstock styles, such as tuning stability or structural integrity, though they’re minimal enough for me to say that picking the headstock for you comes down to your stylistic preferences. 

Tuners (Tuning Machines/Machine Heads)

Next, we have the gatekeepers of musical harmony — the tuning pegs, otherwise referred to as machine heads, tuning machines, or simply tuners.

These are the small knobs found on the headstock that you twist to get your guitar into the perfect pitch by increasing or decreasing the tension. Tuning heads are what we refer to as “geared”, meaning they sit inside a pinion gear and use a cylindrical peg or tuning post to change direction. 

Though it might seem like an unnecessary ultra-mathematical deep dive, it might be worth knowing that the amount of tension you apply with each turn is known as the ‘gear ratio.’ So, for example, let’s say you have a 10:1 gear ratio. This means that for every ten tuning peg turns, you turn the cylinder a full 360 degrees. Higher gear ratios give you better control over your guitar’s tuning. 

While you’ll often find tuning machines in either open or sealed gear variations, open-gear tuners are more common on acoustic guitars. These use exposed gears that you can see and touch, giving you a more rustic, vintage look.

If your guitar doesn’t stay in tune, check this article we made for you: 7 Reasons Why Your Guitar Won’t Stay in Tune – And How to Fix it!

Nut

The nut is the piece of the acoustic guitar that keeps all of your strings in line. Without it, they’d be flapping the wind. 

The nut sits just between the fretboard and the bottom of the headstock and can be made from a number of different materials, including bone, graphite, and hard plastic. The nut plays another crucial role in that it is the last point of contact for the strings before they get wrapped up in the machine heads, delivering vibration throughout the guitar’s neck. 

It works in tandem with the saddle to space the strings out and gives each string a place to sit, thanks to the slits or slots that are cut out of the top. 

While many new guitarists rarely consider it, nut slot depth is a crucial factor. Nut slot depth that is too deep may cause fret buzz, while nut slot depth that is too shallow may not be able to hold onto the strings. Making sure your guitar has a high-quality, and perfectly set up nut for your strings is essential to your guitar’s overall stability.

To learn about nut width of a guitar that affects the playability a lot, check this guide we made: The Guitar Nut Width Explained

Check our guitar nut materials guide here.

Neck

The neck is the middleman in this deal, connecting the headstock to the body. Without it, your acoustic guitar would be a shapeless, stringless blob.

Necks are often fixed to the body of the guitar using glue, though some manufacturers will bolt them into place(more common with electric guitars). 

Longer necks have a longer scale length or long distance between the nut and saddle. While it’s debatable, many players equate longer scale lengths to brighter tones and shorter scale lengths to a warmer tones. 

What you really want to pay attention to is how wide the neck is. Most classical acoustic guitars, for example, are manufactured with fingerstyle in mind, so they often have much wider necks (around 50 mm) with more space between the individual strings to make them easier to play. 

Check our picks for the best acoustic fingerstyle guitars here.

On the other hand, steel string acoustic guitars typically have a neck width of around 43mm or so, better for players with smaller hands. 

Beyond the width, necks also come in unique shapes, which guitar manufacturers often refer to as neck profiles. 

Check out our guitar neck shape guide to learn more. 

Frets and Fret Wires

Next, we have the fret wires, which are like the rungs on the music ladder. These small metal dividers sit atop the neck of your guitar, allowing you to climb up and down to reach different chords and notes. Between these fret wires lie the frets, which separate the guitar into semi-tone intervals. 

The majority of acoustic guitars offer somewhere in the realm of 18-20 frets rather than the 24-fret designs used by many electric guitar manufacturers. 

Fret wires are embedded into the fretboard, though the way in which they are embedded has to do with the size and design. The team over at Strings Direct has an excellent article that discusses fret differences and why they matter.

Fret Inlays/Markers

Between each of the fret wires, you’ll find the icing on the cake — the fret inlays. These little designs and patterns that sit inside the fretboard help give your guitar character while indicating the fret number. 

They can be super helpful for guitarists who are learning to orient themselves across the neck. 

The industry standard for inlay placement is on frets 3, 5, 7, 9, 12, 15, 19, and 21. While they come in a wide range of sizes and shapes, including dots, squares, trapezoids, and more, you’ll often find double inlays on the 12th fret, which indicates the octave change.

The material that these inlays are made out of can vary, though some of the most common materials are plastic, abalone, and mother of pearl.

Fretboard/Fingerboard

The fretboard is the musical map upon the guitar’s neck, which guides us on our journey to find the right notes and chords. It’s typically made out of one of many tonewoods, including ebony, rosewood, or maple, and the types of wood can have an impact on the tone. 

Rosewood is one of the most popular tonewood choices for acoustic guitar, as it’s slightly oilier than other types of wood, great for creating a warm tone and reducing finger tension.

Check our full how to clean guitar fretboard guide.

Strings

Of course, we couldn’t play our acoustic guitars without strings. The type of strings you choose can have a major impact on the tone. 

At the top of the string tree, we have the two most common types of strings — nylon and steel.

• Nylon strings, which are often found on classical guitars, produce a warmer, softer, and mellower town
• Steel strings, which are often found on standard acoustic guitars, are louder and brighter, making them better for rock, pop, or country music. 

Within these two umbrella categories lies a plethora of subcategories. For example, some acoustic guitarists prefer to buy steel strings that are coated with thin nanoweb or polyweb material, which protects them from dirt and sweat to extend their lives. The durability and tone can also be impacted by the alloy choice, such as stainless steel or phosphor bronze.

Your string choice will ultimately depend on your personal preference, though we also recommend checking out our how to choose the right guitar strings guide to get you started. 

Truss Rod

The truss rod is the spine of your acoustic guitar. It lies beneath the surface and helps the wood withstand the enormous amount of pressure it is put under by the strings. 

This metal tensioning bar, which runs through the neck of the guitar, is adjustable, allowing you to modify the amount of neck relief or bow your guitar has. Most steel-string acoustics require truss rods, though many classical guitars don’t, as nylon strings don’t create as much tension.

With acoustic guitars, you can access the truss rod through the soundhole from the end of the neck.

Learn more about truss rods here.

Heel/Neck Joint

The heel or neck joint is the place in which the neck is jointed to the body. 

Most acoustic guitar manufacturers use a dovetail joint attached with glue. This type of joint has been somewhat of a design staple for many millennia.

Back And Sides

The back and sides of your acoustic guitar will often use the same wood types. For example, you might have an acoustic with a spruce top that is paired with Rosewood back and sides.

Not only do the back and sides provide stability to hold your guitar together, but they also stabilize your guitar and can also affect the sound.

Top/Soundboard

The top of your acoustic guitar features the soundboard, which is more flexible than the back and sides, as it is responsible for your guitar’s projection. 

Without the soundboard, you wouldn’t have a surface to amplify your string vibrations or deliver unique tonal characteristics. The top is the piece of acoustic guitar that affects the sound of the instrument the most.

Tops/soundboards are usually made out of either laminated wood or solid wood. To learn more about the differences between these, check this Laminated vs Solid Wood Guitars article.

Cutaway

Once upon a time, acoustic guitar manufacturers began adding cutaways to their body designs, allowing for easier access to the higher frets. This small indentation lies in the upper portion of the body, adjacent to the neck. One of our favorite cutaways is the Taylor Guitars Grand Auditorium.

Soundhole

The soundhole is the part of the acoustic guitar that makes it speak. Without it, the vibrations created from your strings would have nowhere to escape and project out into the world. Most acoustic guitars use circular-shaped soundholes, though you’ll sometimes find unique variations, such as F-holes, in classical, acoustic, and acoustic-electric guitars across the board. 

Other guitar manufacturers, such as Martin Guitars and Bourgeois, have acoustic guitars in their lineup with larger-than-standard soundholes.

Check Acoustic Guitars With F-Holes here.

Check Acoustic Guitars With Offset Soundholes here.

Check Acoustic Guitars Without Soundhole here.

Check Acoustic Guitars With Side Sound Ports here.

Rosette

Around the soundhole, we have the rosette, which is a series of decorative rings. However, while they appear to be purely aesthetic, they are also functional in the way they reinforce the wood surrounding the soundhole. Without the rosette, your acoustic guitar would be more susceptible to cracking.

Pickguard / Scratch Plate

As you may have guessed, the pickguard or scratch plate is the element that stops you from scratching your guitar when flatpicking or strumming. This guard, which is typically constructed from multi-ply laminated plastic, sits just below the soundhole You wouldn’t often find these on classical guitars, as many classical guitarists don’t play with picks. 

However, many flamenco guitarists will use golpeadors, which are clear protective plates that protect the soundboard from fast and aggressive strumming. 

Binding

Binding is the strip that joins the top and sides of your acoustic guitar. It can be made out of numerous materials, such as PVC plastic, or vinyl. Not only does it act as a decorative element, giving your acoustic guitar a unique character, but it also protects the guitar’s edges, which are susceptible to damage.

Lower Bout, Waist, And Upper Bout

The body of an acoustic guitar is split into two main sections — the upper bout, which is the upper half of the body, and the lower bout, which is the lower half of the body. These two bouts are separated by a narrow section called a waist.

The way in which these are designed can greatly affect the tone of the instrument. For example, acoustic guitars with wider lower bouts will have greater resonance with more space for air to move around, giving them better low-frequency output.

Bridge and Bridge Pins

The strings move from the tuning heads on the headstock, all the way down the neck, past the soundhole, and into the bridge, which fixes the strings to the body. We have an article on the various guitar bridge types, which we highly recommend checking out. 

If you are shopping for used guitars, bridge is one crucial part to inspect. Learn more about buying used guitars here.

Most standard acoustic guitars, however, utilize standard rosewood or ebony timber with small holes and bridge pins that lock the strings in place. With that said, some manufacturers have started outputting acoustic guitars with pinless bridges.

Some rare acoustic guitars can even have a whammy bar on them.

Saddle

Atop the bridge sits the saddle, which is typically made to match the nut. 

However, rather than being arranged perpendicular to the neck like the nut, the saddle is often slightly angled so that the end nearest the low strings is closest to the bridge pins, allowing for correct intonation.

Some Takamine acoustic guitars use split saddles, the goal with this is to increase the intonation even more.

Some acoustic guitar have adjustable saddles, although it is rare, you can find some of the currently available models and more info about them here: Acoustic Guitars With Adjustable Saddle

Bracing

Within every acoustic guitar, you’ll find bracing, which is essentially the structural support of the body. Bracing uses lighter wood materials that can maintain structure without impacting resonance, though there are many types of bracing, depending on the type of guitar.

For example, most steel-string acoustic guitars use X-bracing, while most classical guitars use fan bracing.

Strap Buttons

Want the freedom to rock out without being stuck to your seat? 

This is where strap buttons come in. They support the strap on both ends of your acoustic guitar so you can stand and play. However, note that many classical guitars do not come with strap buttons built-in, as they aren’t meant to be played standing up.

Electronics & Preamp & Tuner

Many modern acoustic guitars come with electronics built-in. Some use built-in tuners, helping you to stay in tune on the go, while others have jacks and amplification components that allow you to plug into amps or PA systems, which are great for playing live or adding post-effects, such as reverb, chorus, or delay.

Some acoustic guitars that plug in use built-in preamps, which you can enable and disable as needed. Preamps are used to amplify the sound of your guitar without a need for an external amplifier so that if you’re playing live with a full band, you and the audience will be able to hear your acoustic cutting through (you of course need a speaker or acoustic guitar amplifier to hear the amplified sound).

One of our favorite acoustic guitars with built-in electronics is the Yamaha FG-TA Transacoustic.

Pickups

Even if you don’t have an acoustic guitar that come with built-in amplification, you can always add pickups later down the line to reproduce your tone with more volume. 

We have a very in-depth article we wrote on the different types of acoustic guitar pickups, from piezo to microphone pickups, which we highly recommend checking out if you want to see how you can take your acoustic guitar to the next level.

Acoustic Guitars vs Electric Guitars – Main Differences

Though they might play the same, acoustic and electric guitars are very different in many ways. Here are a few of the main things that set these two apart:

• Sound – Acoustic guitars (beyond those with built-in amplification electronics) reproduce sound solely through string and wood vibration, while electric guitars use pickups and external amplifiers. 
• Playability – Acoustic guitars can be slightly more difficult to play with thicker, heavier strings, and thicker neck.
• Construction – Acoustic guitars are often much larger with hollow bodies, while electric guitars are often much smaller with solid bodies. 

For a more in-depth list of differences, check out our acoustic vs. electric guitar guide.

FAQ

Should Beginners Learn to Identify Different Parts of Acoustic Guitar?

Absolutely! It can be very beneficial for beginners to learn how the various components of the acoustic guitar function. 

What Parts of Acoustic Guitar Affect Sound The Most?

• Soundboard/top
• Bridge
• Nut & saddle
• Strings
• Body shape
• Soundhole size and shape
• Back & sides

What Parts of Acoustic Guitar Affect Playability The Most?

• Neck profile
• Fretboard radius
• Frets
• Body shape & size
• Scale length

Check these articles:

–Acoustic Guitars With Thin Necks

–Guitars With Thick Necks

–Best Acoustic Guitars for Small Hands

–Best Guitar Neck Shapes for Small Hands

Conclusion

There you have it, the anatomy of an acoustic guitar, from the headstock all the way down to the strap button!

We’ve unraveled everything from the magic of the fretboard to the indispensability of the truss rod, and whether you’re a beginner or a seasoned pro, having an understanding of the anatomy of your instrument is crucial, as it’ll make caring for your instrument and keeping it in tip-top shape easier. 

We hope you feel more confident as a guitarist now! If you have any questions, just ask in the comments, we are happy to help you out.

Happy playing!

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