‘Voicing’ an electric guitar?!
What does ‘voicing’ even mean?
When luthiers talk about ‘voicing’ a guitar, it is typically in the context of an acoustic guitar. A lot goes into tap-tuning guitar plates, designing bracing patterns, and strategies for carving those braces that contribute to the ‘voice’ of an acoustic instrument. Can the same be said for an electric guitar?
There is considerable debate surrounding the question, ‘does wood choice make a difference in the tone of an electric guitar?’ Many folks would argue that it makes absolutely no difference at all. Others would say that there is some difference. Regardless of where your opinion falls in this debate, I think it is clear that there are other factors that make a much larger difference.
Let’s explore those.
Pickup selection
There is a clear difference between the tone of certain categories of pickups. This is a good place to start when trying to realize a certain ‘voice’ you hear in your head. At the risk of oversimplifying, they can be generalized as such:
Single Coils: Clear, Bright, Chime-y, and will cut through a mix. The middle positions can quack like a duck (which some people - including myself - really love). Mark Knopler, David Gilmore, and Jeff Beck are good examples of the single coil sound.
P90’s or ‘Soapbar’ pickups: Warm and Rich, Thicker Midrange, Dynamic. More Tonally Balanced than traditional single coils. Can get ‘snarly’ and aggressive when pushed into overdrive. John Lennon, Paul McCartney, Grant Green, Neil Young are good examples of this sound.
Humbuckers: Thick, Warm, Harmonically Complex, Smooth, and Loud. They are great for overdriven or distorted sounds. B.B King, Derek Trucks, Frank Zappa are good examples of this sound.
‘Sensing Window’ considerations
Each of these pickups has a different ‘window’ of the string that it can ‘hear’. Consider this…
Generally, the narrower the area of string that a pickup can ‘hear’, the more harmonic content. The wider the area, the more fundamental content is present. This makes sense if you think about it in conjunction with pickup placement. A Tele bridge pickup is sensing a narrow window of the string, while also listening to the string closest to the most harmonic-rich part of the string by the bridge (see below). A perfect recipe for some twang-y goodness!
Pickup Placement
Why is this so often overlooked? It makes a huge impact on an instrument’s tone! In the 1970’s, Fender famously moved the bridge pickup on Jazz Basses 0.4 inches closer to the bridge. The result of this seemingly small change was significant! It resulted in a brighter, punchier sound, with significantly more harmonic content.
As you move the pickup, you can expect the following results:
The loss in volume is easily overcome. Pickup manufacturers wind the bridge pickups to produce more output for this very reason. The big difference then lies in the tone. Moving closer to the bridge not only make the tone brighter, but significantly increases the harmonic content. The part of the vibrating string the pickup ‘listens to’ simply has more harmonics in it.
If you take this into account when selecting the type of pickup, you can really refine the voice of the instrument through experimentation and thoughtful pickup placement.
Capacitor and Potentiometer values
Pots: For passive pickups, it is typical to use either 250k or 500k pots. 250k pots tend to impart a warmer tone, and are typically used to counteract the very bright natural tone of single coil pickups. 500k pots are inherently brighter and are usually matched with humbuckers and P90s. Selecting between ‘audio taper’ and ‘linear taper’ pots can also have a big effect the perceived usefulness of the range of the tone control.
Capacitor values also can have a huge effect on the tone. Generally speaking, the large the value of capacitor, the more high content it will roll off in a tone circuit, making for a darker tone. However, it is difficult to quantify exactly where the cutoff frequencies are for a given capacitor because it depends on the impedence of the pickup, the value of the pots, and other factors. However, here is a crude example just to illustrate the point.
Let’s assume the same pickup and pot value:
0.047 µF (common for single-coils) → can cut well into the upper mids when rolled down, resulting in a darker sound.
0.022 µF (common for humbuckers) → mainly trims the treble, leaving more mids intact.
0.010 µF or smaller → just smooths out the sparkle without getting muddy.
Again, this should be taken with a grain of salt as there are other mitigating factors.
Capacitor types: This might be more of a smoke-and-mirrors type thing. The real issue here IMHO is one of consistency.
There are three types of capacitors:
Ceramic (above left) - cheap and available. Typically found on lower end instruments. Tolerances are not very tight, and caps can vary wildly from one to another. This is the reason they get a bad rap and why we avoid them.
Paper-in-oil (above center) - Legendary (Bumblebee caps) from the golden era of Gibson. NOS ones can be purchased for ridiculous prices. Difficult to source and questionable as to whether they are actually better or not.
Polypropylene (e.g. Orange Drop - above right) - Easily accessible though a little more expensive. Much tighter tolerances (consistency!)
Other factors…
Scale length: Longer (25.5” ‘Fender’ scale length) usually equates to more clarity and definition as opposed to a shorter 24.75” scale
Weight: Ergonomics aside, a lighter guitar will typically be more resonant. I would argue that a lighter instrument will allow more of the character of the wood selection to impact the overall tone. A heavier instrument on the other hand relies more on the strings and electronics exclusively as the amount of energy the vibrating string generates is not enough to really get the body vibrating. At least compared to a lighter instrument.
To wrap up…
As you can see, there are a lot of factors that go into ‘voicing’ an electric guitar. When taking a holistic approach to the different factors, it is possible to create almost any kind of ‘voice’ that can be imagined!
Visiting the Salvage Yard
It is always fun to go take a stroll around the racks and bins at the local salvage yard.
What do we have here?
Using salvaged or reclaimed lumber plays heavily into our purpose and brand identity. It is extremely interesting going through the racks to look for suitable lumber that might one day find a second life as a musical instrument.
They have a large selection of wood to take a look at!
You can find very interesting pieces. They have a large selection of Teredo Fir that was harvested from old log booms.
Lot of holes!
In the Pacific Northwest, it was very common to float felled lumber to the sawmills through the Puget Sound via tugboats pulling large ‘rafts’ of lumber. You can still see this in practice today, though it is less common. The log-booms on the outside of these ‘rafts’ were use to corral all the free floating lumber and were reused many times. Some of these old log-booms have been partially submerged for over 50 years!
In that time, the wood would become exposed to shipworms, also known as Teredo Clams. The shipworms would bore through the wood, living their entire life inside leaving a network of tunnels. When book-matched, it looks like a psychedelic Rorschach test.
Bookmatched Teredo Fir
At some point, I would like to try one of these sets as a drop-top for an electric guitar! In the meantime, I was able to score some Doug Fir ship-lap that will come in handy for a future build.
And of course, a critical part of the wood selection process is to try it out!!!
Yep, that one sounds good!
New Model Announced
Now developing the Cartwright Sparrow. The Sparrow is a bolt-on construction double cutaway guitar.
Specs:
Frets: 21
Scale Length: 25.5 inches
Pickups: Lollar P-90s
Electronics: 2 Volume, 2 Tone, with 3 way switch. CTS Pots, Switchcraft pickup selector switch, orange drop caps
Bridge: Fixed
Available in Pine, Alder, Ash, and Moso Bamboo
Finishes: Amber, Black, and Red