About Guitar Necks

We hear and read a lot of things about guitar necks, neck to body joint type, material, grain orientation, reinforcement, laminations... But what does science say ?

Let’s find out !

Preliminary word

This article sets out to explore guitar neck joint types through an objective lens, focusing on tangible aspects that influence a guitar's sound and playability. By sidelining subjective perceptions and ergonomic considerations, we aim to dissect myths and facts surrounding neck joints, relying on scientific data and empirical evidence. Our goal is to enlighten builders and players alike, providing a foundation for informed decisions based on the intrinsic qualities of each neck joint type. We will not discuss linked topics such as the advantages or disadvantages of certain constructions on ergonomics, playability and balance.

Introduction

In the realm of guitar craftsmanship, the junction where the neck meets the body is not merely a point of physical connection but a pivotal element in defining the instrument's tonal character and structural integrity. This article delves into the intricacies of neck joint types, extending the discourse to the nuanced realms of grain orientation and laminated neck construction. Our aim is to demystify the technical aspects that underpin these design choices, shedding light on their empirical impact on the guitar's sound, devoid of subjective interpretations and ergonomic considerations.

But first, let’s summarize things a little bit

Types of neck joints :

Bolt-On Neck: This type is characterized by the neck being attached to the body with screws, often accompanied by a metal plate. Bolt-on necks are prevalent due to their ease of manufacturing, repairability, and cost-effectiveness. They are supposed to produce a snappier, more twangy tone, attributed to the transfer of resonance between the neck and body being slightly impeded by the joint. This type of neck is most common in electric guitars but can also be found in acoustics, where the bolts are hidden inside the guitar

1. Set Neck: In this construction, the neck and body are made separately but are glued together, typically using a dovetail joint. This method is slightly more complex than bolt-on but less so than neck-through construction. Set necks are supposed to have a better ability to transfer tonal vibrations more efficiently between the neck and body, resulting in a warmer, fuller sound. This joint is particularly popular in acoustic guitars

2. Set-Through Neck: A variation of the set neck, the set-through neck extends further into the guitar body and is also glued in place. While not as common, this type provides a supposed good balance between the bolt-on and neck-through designs, offering enhanced sustain and resonance without the complexity of a full neck-through construction

3. Neck-Through (or Neck-Thru): This design features the neck extending the entire length of the guitar body, with "wings" glued on either side to form the body. This type is supposed to procure excellent sustain and resonance, as there is no separation between the neck and body.

Grain orientation

In the construction of guitar necks, the orientation of the wood grain plays a pivotal role in both the aesthetic and structural integrity of the instrument. The three primary types of grain orientation and cuts are:

1. Plain Sawn (Flat Sawn): This is the most common and cost-effective method, where the wood is cut parallel to the growth rings, resulting in a distinctive "cathedral" grain pattern on the face of the board. While it offers a wide variety of grain patterns and is more sustainable due to minimal waste, plain sawn wood is more susceptible to warping and cupping due to its grain orientation.

2. Quarter Sawn: In this method, the log is cut into quarters and then sawn at a radial angle, producing a straight grain pattern with the growth rings intersecting the face of the board at 60 to 90 degrees. Quarter sawn wood is known for its stability and resistance to warping, with a unique appearance that includes the possibility of dramatic flecking, especially in woods like oak. However, this method is more labor-intensive and produces more waste than plain sawing, making it more expensive.

3. Rift Sawn: Similar to quarter sawn, but with the growth rings at a 30 to 60-degree angle to the face of the board, rift sawn wood offers the most linear and consistent grain pattern. It is the most dimensionally stable but also the most labor-intensive and wasteful method, resulting in higher costs.

Each of these grain orientations offers unique advantages and challenges for guitar builders, from the aesthetic appeal of the wood's grain pattern to its structural stability and response to environmental changes. When selecting wood for a guitar neck, builders must consider these factors in light of the desired tone, appearance, and durability of the instrument.

Laminated necks

In guitar construction, there are two main types of neck constructions: one-piece necks and laminated (multi-laminated) necks, each with its own set of advantages and considerations.

One-Piece Necks:

One-piece necks are crafted from a single piece of wood, which is often preferred for its simplicity and the tonal qualities it imparts to the instrument. These necks are favored in genres where sustain and clarity are crucial, as the uninterrupted wood grain can enhance resonance and vibration transfer from the strings to the body of the guitar. However, one-piece necks may be more prone to warping or twisting over time due to environmental factors like humidity and temperature changes.

Laminated (Multi-Laminated) Necks:

Laminated necks, on the other hand, consist of multiple layers of wood glued together. This construction method allows luthiers to combine different types of wood, each contributing unique properties to create a neck that is both stable and tonally versatile. Laminated necks are known for their increased strength and resistance to warping or twisting, making them a suitable choice for a wide range of playing styles and musical genres. The visual appeal of laminated necks is also a significant factor, as the layers can create striking patterns and contrasts.

The choice between a one-piece and a laminated neck depends on various factors, including the desired tonal characteristics, playability, and the aesthetic preferences of the player. While one-piece necks offer a traditional look and feel with potentially enhanced tonal qualities, laminated necks provide added stability and the opportunity for unique visual designs.

When it comes to building a laminated neck, the process involves careful selection and alignment of the wood strips to ensure structural integrity and visual symmetry. The layers are glued under pressure to form a strong bond, creating a neck blank that is then shaped into the final neck profile. This method not only enhances the neck's strength and stability but also allows for the use of thinner wood pieces that might otherwise be unsuitable for neck construction.

In summary, both one-piece and laminated necks have their place in guitar construction, each offering different benefits to the guitar's overall feel, playability, and sound. The choice between them will largely depend on the specific needs and preferences of the guitarist, as well as the particular design goals of the luthier.

Neck Reinforcements & Truss Rods

Guitar neck reinforcement is a crucial aspect of guitar construction, aimed at enhancing the stability and durability of the neck. Two popular materials used for neck reinforcement are carbon fiber and titanium, each offering distinct advantages.

Carbon fiber is known for its high strength-to-weight ratio and is often used in guitar necks to provide added stiffness and resistance to warping. The use of carbon fiber in guitars ranges from reinforcing necks with bars or rods to creating exoskeletons around the neck for added stability

Titanium, on the other hand, is valued for its lightweight properties and exceptional strength. It's not designed to hold the neck in place but to keep it straight, allowing the neck's elasticity to resist tension from strings, temperature, and humidity. The material is processed through cold rolling to achieve optimal hardness and elasticity, making it an excellent choice for neck reinforcement.

When choosing between carbon fiber and titanium for neck reinforcement, the decision often comes down to the specific needs of the instrument and the preferences of the player or builder.

Finally, truss rods come in different designs, such as simple or dual action. These don’t really affect our discussion, but the way they are installed can modify significantly a guitar neck’s behaviour. We will discuss this later.

Myth vs. Reality

The construction of a guitar, particularly how the neck is joined to the body, has long been a topic of debate among musicians, luthiers, and enthusiasts. Common wisdom suggests that the method of joining the neck to the body—whether through bolt-on, set-in, or neck-through techniques—has significant implications for the instrument's tone, sustain, and overall playability. Let's delve into these myths and contrast them with scientific findings to shed light on the reality.

Myth: Neck-Through Construction Offers Superior Sustain and Tone

One prevalent myth is that neck-through construction, where the neck extends through the entire length of the body, provides superior sustain and tone quality compared to bolt-on or set-in necks.

Reality: Studies, including a comprehensive analysis by Pate et al., have challenged this notion. Their research found no consensus among guitarists regarding the superiority of one joint type over another in terms of sustain and tone. The study combined objective measurements, such as driving-point conductance, with subjective evaluations by professional guitarists. The results indicate that factors other than the neck joint type, such as the material properties and overall construction of the guitar, play more significant roles in determining sustain and tone.

Myth: Bolt-On Necks Are Inferior in Tone and Quality

Bolt-on necks are often regarded as less desirable, supposedly offering less sustain and a "cheaper" tone compared to set-in or neck-through necks.

Reality: The choice between bolt-on and set-in necks involves trade-offs in terms of cost, ease of repair, and manufacturing simplicity. The notion that bolt-on necks are inherently inferior has been debunked by various studies and practical observations. For instance, the work by Stanciu et al. on the mechanical behavior of guitar necks under stress does not directly correlate the neck joint type with a significant difference in tonal quality or sustain. It's more about the overall design and material choice than merely the neck joint type.

Myth: Set-In Necks Provide Warmer Tones

Set-in necks, where the neck is glued to the body, are often associated with a warmer, fuller tone, presumably due to better energy transfer between the neck and body.

Reality: While set-in necks might provide a different feel and potentially affect the instrument's resonance due to the larger contact area between the neck and body, the warmth of the tone is influenced by a multitude of factors. The type of wood, the guitar's body structure, and even the strings and pickups have substantial impacts. The study by Ray et al. highlights the importance of material choice and construction technique over the simplistic view of neck joint type dictating tone warmth.

Myth: Material and Grain Orientation of the Neck Have Minimal Impact

Some believe that the material and grain orientation of the neck (e.g., quartersawn vs. flatsawn) have minimal impact on the guitar's performance and sound.

Reality: The choice of wood and its grain orientation significantly affects the neck's stiffness, response to environmental changes, and overall tonal characteristics. The study by Puszynski provides insights into how different wood species and their mechanical properties, including grain orientation, influence the acoustic properties of electric guitars. The research underscores the critical role of material choice in achieving desired sound qualities.

Conclusion

The myths surrounding guitar neck joint types and their impact on tone and sustain are often oversimplified and lack scientific backing. Comprehensive studies and empirical evidence suggest that while the neck joint type does contribute to the instrument's overall feel and playability, its effect on tone and sustain is just one part of a complex interplay of factors, including material choice, construction quality, and the individual components of the guitar. Understanding these nuances allows musicians and builders to make more informed decisions based on their specific needs and preferences, rather than adhering to pervasive myths.

Myth: One-Piece Necks Offer Superior Tone

A common myth is that one-piece necks, made from a single piece of wood, inherently provide a better tone due to the uninterrupted wood grain which supposedly enhances vibration transfer and resonance.

Reality: While one-piece necks are praised for their traditional construction and aesthetic simplicity, the superiority of their tone is not absolute. The tone of a guitar is the result of a complex interplay of various factors, including the body's material and construction, the type of strings, and the electronics used. Laminated necks, which comprise multiple layers of wood glued together, can also offer excellent tonal qualities. The lamination process can even enhance certain acoustic properties by combining different wood types, each contributing its unique tonal characteristics.

Myth: Laminated Necks Lack Sustain

There's a notion that laminated necks, due to their glued layers, suffer from reduced sustain compared to one-piece necks.

Reality: Laminated necks can actually provide comparable, if not enhanced, sustain relative to one-piece necks. The glue used in laminated necks does not significantly dampen vibration. In fact, the strategic layering in laminated necks can increase stiffness and stability, which are crucial for sustain. The precise construction and quality of the lamination process are more critical factors in determining the neck's performance.

Myth: Laminated Necks Are Only for Cheap Guitars

Some believe laminated necks are a cost-cutting measure reserved for lower-end guitars.

Reality: While laminated necks can be cost-effective, they are not exclusively found in budget guitars. Many high-end guitar manufacturers use laminated necks for their superior stability and resistance to warping and twisting. The choice to use a laminated neck often stems from a design perspective, aiming for a specific aesthetic or to achieve certain physical properties, rather than purely for economic reasons.

Myth: One-Piece Necks Are More Prone to Warping

The myth suggests that one-piece necks, being made from a single piece of wood, are more susceptible to environmental changes and more likely to warp over time.

Reality: While it's true that wood is a natural material susceptible to environmental conditions, modern one-piece necks are constructed with this in mind. Techniques such as quarter-sawing the wood and incorporating adjustable truss rods are used to mitigate the risk of warping. Proper care and maintenance are also crucial in preserving the neck's integrity. It's not the construction method alone but the combination of material choice, construction technique, and maintenance that determines a neck's resilience.

Conclusion

The debate between laminated and one-piece guitar necks is nuanced, with each type offering its own set of advantages. The choice between a laminated and one-piece neck should be guided by the specific requirements of the player and the intended use of the instrument, rather than by generalized myths. High-quality guitars can be made with either type of neck, and the ultimate test is in the playing experience and the sound produced.