Guitar Woods (Part 1)

Instrument Woods, Soundwaves & Electric Guitars 

In this 3 part series we will discuss the importance of high quality wood for building instruments, and electric guitars in particular.  In Part 2 & 3 we will go into guitar pickups and electronics.  We will also take a stab at some of the most widely debate topics surrounding electric guitars; What are tonewoods? Is tonewood a legit designation? Do woods or materials actually affect the tone of an electric guitar?  These questions are have been widely debated for years amongst guitar players, engineers and researchers.  Bear with us as there is a lot of information here, and some wood principles we need to explain.

Do different woods affect electric guitar tone?

In our humble opinion the short answer is yes, different woods, or any material for that matter, imparts its own undertones (or lack thereof) to the sound coming out of your amplifier. Do they affect tone as much as on an acoustic, absolutely not due to the influence of the pickups themselves, but they still have a significant effect on your tone.  Here’s the gist…

Guitar pickups create small electrical waveforms based on vibration of metal strings, and these are carried to your guitar amplifier.  The guitar string(s) initially vibrate from plucking or strumming them, but they also vibrate due to secondary vibrations traveling through the guitar neck and body and ultimately back through the strings.  The pickups also vibrate a little since they are mounted to the guitar.  Anyway, all these vibrations are transformed into your guitar’s signal and create the overall sound of your guitar.  A completely ‘dead’ material that does not transfer sound well will have very little effect on an electric guitar, but wood is very ‘alive’. 

One more thing, let’s assume for a moment that wood choice does NOT affect tone in an electric guitar.  The wood choice would still have an effect on the stability of the guitar neck, and wood choice would directly affect the sustain or resonance of the notes played, even though we are assuming in this example tone would not be influenced by wood choice. 

Well, we’ve done it now. Pandora’s box is open and we are bracing ourselves for the feedback.   Maybe you’re on board, maybe you completely disagree, or maybe you need to know more before making an informed opinion.  We’ll explain our point of view on ‘tonewoods’, but first let’s review some basic facts about wood and how it’s used for making instruments.

What is instrument grade wood?

Let’s start with what instrument grade wood is.  In order to build a strong, stable, high-quality instruments that are largely free of natural defects, most high-end builders insist on using First and Second (FAS) grade lumber, and secondly luthiers like to be pretty particular about grain direction (orientation of wood fibers).  Out of all the lumber produced in the world, about 1-3% meets the standards of most luthiers.  Without getting to bogged down in the details, luthiers stick to rigid standards when it comes to wood so that that their instruments remain stable, resonate what the musician is playing, and look aesthetically pleasing to the eye. 

Okay, so how does wood affect tone?

There are many different properties of wood that affect the tone of an instrument.  Everything from thickness of the wood, moisture content, physical structure, to the composition of the wood play into how your instrument will sound.  Here’s a simple example to illustrate the varying properties of different woods. A very rubbery wood or flexible wood such as cork will deaden soundwaves as they pass through the spongy material, whereas a rigid and springy piece of wood will allow those same soundwaves to ‘ring’ through. 

Let’s take a step back from wood for the moment and imagine tossing a stone into a glassy smooth lake.  What happens to the water’s surface when the stone hits the lake? It causes a set of ripples across the surface, right? Those ripples, or waves, travel uniformly across the water in perfect rings until they bounce off the shoreline or fade away in the distance.  Now imagine a dock with pillars coming out of the water. What do those waves from your stone do when the hit the dock pillars? They break out into smaller waves, dissipate some, and deflect in different directions. In other words, the simple wave rings become more complex and distorted as they run into things like the dock pillars.

Now let’s take that wave principle and apply it to wood.  When soundwaves hit different structures within the wood such as a knot or defect, the soundwaves will deflect and break up the same as the waves that hit the dock pillars.  Luthiers can select woods with varying properties, which influence the notes you play, and in the process impart different character or color to your overall sound.  Since wood is an elaborate organic material, it accentuates and filters different frequencies to create rich complex sounds. Some woods are extremely straight, springy and uniform, and therefore allow soundwaves to travel easily and remain uniform, while other woods can be very wavy, dense, spongy or complex, which can filter certain frequencies, add unique undertones and even deaden the sound. There are many factors related to mechanical vibrations and resonant frequencies that we will not dive into here, but hopefully you agree with the basic principle that material choice and it’s composition affect how well different frequencies or soundwaves travel through the chosen material. With that being said, now we fall into the great Tonewood debate.