This entire project is heavily influenced both by the lessons learned from building my first electric mandolin. I also used various electric guitars as a reference while in the design stage. I wanted to create a design that would be unique, while still learning from proven construction techniques as well as aesthetic, ergonomic and functional body shapes.
Instead of the relatively unusual headless design of my first emando, I wanted to create a much more ďtraditionalĒ electric guitar design that would hopefully avoid some of the problems of my first electric mandolin. The ergonomics were a definite problem with my last design. The body was very small which made it impossible to hold in the way you would an electric guitar or even a mandolin. I also didnít add strap buttons so it couldnít be played with a strap. The jack further hurt the ergonomics since it was in the way of the best position for holding the mandolin. There really isnít an easy way to support the mandolin at all, and that awkwardness really detracted from the enjoy ability of the instrument.
For this EOM I made sure to allow for easy playing in the same position as an electric guitar is usually held. It is possible to comfortably rest the lower bout on your right thigh while supporting and stabilizing the body with the chest relief as most solid body guitars are meant to be held while sitting. With the addition of strap buttons on the horn and the end of the body you can use any guitar strap to hold the EOM. It also can be held in the classical guitar style as some heavy metal guitarists hold their guitars with the neck at 45 degrees to the ground, the waist on your left thigh and the center of the lower bout resting on the right thigh.
The OEM has a full 24 frets as most Ibanez guitars have. To reach these frets, the I used many of the modern techniques used on the Ibanez guitars and most custom shop guitars to allow for easier access to the upper frets. The neck meets the body at the 17th fret with a contoured and thinned heel and neck for comfortable playing in all positions and a smooth transition to the positions over the body. The neck is fully contoured to flow seamlessly and smoothly into the heel of the body unlike most manufacturers which transition to a squared off neck profile where it fits to the body.
The basic aesthetic design is the fairly common double cutaway electric guitar design which is used by a variety of very different modern guitar manufacturers. This EOM is somewhere in-between the very traditional looking Stratocaster, designed in the 50ís, and the modern, angular Ibanez designs with a rounder bottom curve that departs from most double cutaway designs. In fact, the design is heavily influenced in many ways by both designs as well as many custom shop guitars.
It was a challenge to create a design that would make anyone instantly think guitar when they see it rather than a bass or any other instrument. It has a number of things going against it, such as its four strings and a much narrower neck, both of which make you think bass. I played with the proportions extensively to make sure the EOM would appear guitar like. The most important dimension to accomplish this was the width and overall size of the body compared with the string length. (A bassís body is much smaller than a guitarís for its string length and in absolute terms. Ironically, this seems to be especially true the more strings and frets a bass has.) The other important factor is the neckís width compared with the body size of the instrument. (A bassís neck is thinner and narrower.) The placement of the body in relation to the strings and the length of the neck are also an important and somewhat related factor (The strings of a bass tend to stop at the very end of the body.) Of course, it isnít possible to change some factors such as the width of the neck or the string spacing or it will change the playability of the instrument. I ultimately had to split the difference between these different factors to make the narrow neck seem like a wide six string guitar neck without making such a small body that it looks like a mini-bass. This meant making a body that was in-between the size it should be for the scale length of the instrument and the size it should be for the neckís width. I also overlaid the design on scaled-down full size guitars to check that the proportions would be correct.
The pickups are top mounted without a cover leaving the cavity exposed. Along with the simplicity and cleanness of this style, it also highlights the rugged and mechanical style that is very popular with heavy metal and rock guitarists. I used all chrome hardware to complement the maple neck and black of the body and to continue the sleek, modern styling.
Scale Length and Tuning
I used a 22.27 inch scale length so that I could modify a standard 25 inch scale length, pre slotted guitar fretboard (available at most lutherie suppliers) by cutting it off so the nut would be positioned where the second fret of a guitar would normally be (the same thing could be done to a 25.5 inch scale guitar fretboard resulting in a 22.7 inch scale length.) Here is another excerpt for the proposal on the technical justification for this scale length:
An octave mandolin typically has a scale length of about 20 to 22 inches. Their eight strings are arranged in four courses which are tuned to GDAE an octave below a mandolin. My EOM design will use four strings with a 22.27 inch scale length. This scale length will allow me to use standard guitar strings --which are widely available and inexpensive-- while still being able to tune the EOM to both GDAE and EBF#Db (in fifths starting on an E). The E tuning should make it easier to play guitar parts without having to transpose the part while still being able to reach the low E, F, and F# notes which lie outside of the range of an EOM tuned to GDAE.
Although I refer to it as an EOM, this instrument could also be called a tenor guitar. Tenor guitars typically have a scale length of 21 to 23 inches and four strings. They are most commonly tuned to in fifths to CGDA, but are also tuned EADG, DGBE, GDGD, GDAD, GCEA or, as I plan as one of my primary tunings, to GDAE. It may be more accurate call it a tenor guitar in since they use only four strings not the eight strings in four courses that an octave mandolin has. It would allow me to avoid more passive aggressive emails like the ones that I received about my other four string mandolin projects that read something like ďDonít mandolins have 8 strings?Ē Still, Electric Tenor Guitar just doesnít sound as nice as Electric Octave Mandolin in my opinion. I also think of the instrument as a mandolin more than any type of guitar due to its tuning.