Thoughts on crossover guitars

All this research has prompted some observations, first about what a crossover guitar needs, and secondly about what traditional classical guitarists could learn from the features of a crossover guitar. I expect this to be controversial!

It is my belief that a nut width of 48mm on a nylon-string guitar would be just fine for many guitarists, even those who play classical guitar exclusively. It provides considerably wider string spacing (at 8mm between strings) than what you find on most steel-string guitars. It is noticeably narrower than the 9mm string-to-string spacing you find on a traditional classical guitar with its 52mm nut width. It really does make a difference. If you are not already accustomed to a traditional classical guitar neck, try it; you’ll like it.

At the other end, however, a crossover classical guitar needs to have a string spread of 57 to 60mm at the bridge saddle. This is the traditional classical width, much wider than that found on most steel-string guitars. The reason for this is that if you are playing traditional classical right-hand finger technique (p i m a), you need a lot of space between the strings to dig in and get a good loud sound.

Virtually all traditional classical guitars have a completely flat fingerboard which has no inlays on the fingerboard or on the side. However, virtually all electric and steel-string acoustic guitars have “side dots” that let the player glance down and determine the fret location of his left hand. All classical guitars should have side dots. There is no drawback to this. And if you’re worried about traditional appearance, don’t be. Nobody can see the side dots except the person playing the guitar.

Furthermore, there is no reason that a classical guitar should have a flat fingerboard. This is an unproductive hold-over from the 18th and 19th century when flat fingerboards were the only kind that luthiers made on plucked string instruments. The primary reason for remaining with the flat fingerboard design is one of ease of manufacture and low cost for the luthier. It does not benefit the player in any way.

Regardless of the width of the neck, some curvature in the fingerboard profile, or radius, is always helpful in making the guitar easier to play. I have read about classical guitars with a very slight curvature, 24-inch or 20-inch (610mm or 510mm). Mine has a 15-inch radius, like a Martin steel-string guitar. A greater curvature, say a 10-inch or 7.5-inch radius like on a Strat, would probably be more than a nylon-string player would want.

The late Thomas Humphrey, builder of the Millenium Guitar, championed a slightly radiused fretboard on his traditionally-proportioned instruments with full-width fingerboards. He mentioned that in addition to comfort and playability, it was helpful to increase the curvature under the bass strings to enable a slightly greater string height to correct problems with string buzzing.

Obviously, it’s easier to plane a flat fretboard and hammer in flat frets. With a radiused design, you have to sand or mill the fretboard to a specific tolerance, and you need to individually bend each piece of fretwire to match that radius before it is hammered in to the fingerboard, in order to get a good fit. Finishing the frets by leveling and polishing is a bit more complicated also. Then you need a radiused profile on the nut and the bridge saddle, and this probably complicates intonation compensation. All this takes time and money, but boy is it worth it to the player.

Cutaways are good. You can play the high notes more easily.

The idea of the cutaway first came from archtop steel-string guitars in the 1930s, and was incorporated in to the design of most solid-body electric guitars. Additionally, many models of steel-string acoustic guitar are available with or without a cutaway.

I won’t offer any verifiable data here, because the cutaway issue has been discussed far and wide for many years. Let’s just say that traditional classical guitarists have not approved of the cutaway because it simply makes the guitar look unlike a traditional classical guitar. The cutaway remains an unpopular option for serious, acoustic classical guitar players. But the cutaway is gaining acceptance. It’s been demonstrated that the presence of a cutaway does not necessarily alter the sound, volume or projection of a guitar.

One of my tenets in this blog is that classical guitars should break from tradition in terms of size and shape if there are innovative new ideas that prove beneficial. So I would like to ask traditional classical players to be more open to new shapes and dimensions for their guitars. Why must all guitars look, externally, just like the ones they built in Europe in the 19th century? If somebody builds a design that’s easier to play yet sounds just as good or better, it shouldn’t be rejected just because it does not look orthodox and conformist.

If you want to do some outside reading, I would refer you to the Web site of the famed and innovative builder Greg Byers, who discusses different designs with regard to scale length. Unfortunately there’s not a lot of information on the Web about Thomas Humphrey’s design principles, since his passing and the abandonment of his Web site and domain. I’m sure you can find many other links. The biggest area of innovation is in the construction of the tops of the guitars and how they are braced, and that’s way outside the scope of my blog.

Which guitar to buy? Part One

I did an inordinate amount of research in order to find a guitar that met my needs. Maybe you can benefit from my experience.

Four or five years ago I got an inexpensive Alvarez classical guitar, a very traditional model except for having a cutaway. It was set up correctly with the usual action, and it played okay for a classical. It had the traditional wide, totally flat fingerboard and fat neck profile. I just could not get used to playing it. My fingers couldn’t easily or properly reach the low strings, even though my hands are normal-sized and I was very careful about my hand position on the neck.

My experience was in playing a Gibson-style archtop jazz acoustic-electric guitar, with a thinner neck and a narrow fingerboard width and a radiused (curved) fingerboard profile. What’s more, playing this standard classical guitar was actually painful to my left hand due to all the extra stretching. I sold the guitar and gave up on playing classical.

So when I decided to go classical earlier this year, I determined to find a crossover guitar, which is a nylon-string classical guitar designed with a neck that is a compromise between the large classical neck and the small, more comfortable neck found on a typical steel-string acoustic guitar or electric guitar.

The crossover guitar is a relatively new product category, and they are gaining popularity. There are many new models arriving on the market from many manufacturers and luthiers.

The crossover classical guitar makes no sense at all to players who have only ever played classical guitar. They see the crossover design as undesireable and inadequate for the classical guitar repertoire and playing style. But that’s not the point! Crossover guitars are specifically for experienced adult, full-grown steel-string and electric guitarists who want to play classical but just can’t deal with those enormous, wide, flat fingerboards and chunky, fat necks.

Most crossover guitars fall into the acoustic-electric category; they are designed to be played plugged in and they don’t put out much volume or a good tone acoustically. But increasingly, there are new models of crossover guitars that sound about as good unplugged as a traditional acoustic classical guitar. After deciding that I needed an acoustic-electric, I changed my mind when I found a well-designed crossover guitar that had a crossover neck on a traditional, full-sized body with good acoustic volume and tone.

So what are the parameters that you should consider in selecting a guitar and its neck?

Fingerboards

Look at any guitar. If you look at the fingerboard, start at the nut, and follow the strings down to the bridge, you’ll see that they describe a long, narrow trapezoid. The string nut has a certain width, and there is a certain width from the center of the lowest string to the center of the highest string; this is called “string spread”. The strings at the bridge have a certain string spread which is wider than the string spread at the nut. And the fingerboard widens in width from the nut down to the end of the fingerboard. Its width at any given point is a function of the string spread at the bridge.

Then there’s radius. A typical classical guitar has a completely flat fingerboard. But most other guitars’ fingerboards have a curved profile, which is much more comfortable to the hand and fingers if you are playing chords. However, the next question is “how much of a radius”?

The conventional design principles follow this sort of logic:

Acoustic guitars like a dreadnought are designed for strumming chords. So they have a narrow fingerboard width, the strings are placed closely together, and the fingerboard is radiused. This is comfortable and easy to play.

However, if you play more complicated music that involves counterpoint, scale patterns, intricate close-position jazz chords, or string bending (on steel-string instruments), or if you fingerpick with several fingers independently rather than strumming with a plectrum, you need something slightly wider in a fingerboard, and you need more space between the strings. Otherwise your fingers on your fretting hand will frequently find themselves too bunched together to play your intricate music correctly. You also want less of a fingerboard radius because a small radius (meaning a pronounced curve in the profile of the fingerboard) interferes with intricate fingering and string bending.

Thus, different kinds of steel-string acoustic guitars and electric guitars are available in a range of nut widths, fingerboard widths, radiuses, and to some degree, string spacing at the bridge.

At the other extreme is the classical guitar, which has the widest fingerboard of all six-string guitars, and has a fingerboard with an infinite radius, which is another way of saying that it has zero curvature or that it is completely flat. The music that you play on a classical guitar requires the most dexterity and independent finger-movement, and the highest degree of counterpoint, of any other style of guitar music; this is the usual rationale given for why a classical guitar has this design.

Modern classical guitars generally follow standardized designs developed by master luthiers in the 1800s and the early 1900s. A few modern guitar designs incorporate radical innovations in materials used in the top and bracing, but it seems to me that almost all guitar builders and luthiers feel duty-bound to use the same neck and fingerboard dimensions, scale length, and body shape (plantilla) as the traditional designs from the 1800s. In other words all the classical guitars you are likely to see today will look virtually the same from the audience’s perspective, but more importantly they all feel the same in the hands of the players. This won’t do for me.

I think this is a mistake. We need guitars that accommodate different players’ personal preferences, and we need innovative designs. Fortunately these are beginning to appear on the market and gain popularity.

I don’t want or need a totally flat fingerboard radius. It’s just uncomfortable, particularly in those times when you make a barre. I don’t need the widest possible fingerboard width, because my left hand is accustomed to fingering music on strings that are more closely spaced. I also don’t want a fat, thick neck. So since there are a range of parameters, how would I decide on the ideal neck for me?

First let’s look at popular guitar designs and their typical measurements (individual models may vary slightly). I have ranked them from the narrowest designs to the widest designs. American measurements are usually expressed as inches with fractions, but to maintain sanity, I’ll convert everything into millimeters.

Scale

length

Nut width

String spread

at nut

String spread

at bridge saddle

Fingerboard radius
Fender Strat (traditional) 647 41 35 54 180    (greatest curvature)
Fender Stratocaster (modern) 647 41 35 54 240
Gibson Les Paul 629 43 36 52 305
Martin dreadnought 647 43 35 58.7 380
Martin fingerstyle 647 45 38 54 380
Parlor Varies

48

40.5

Varies (wide)

380

Traditional classical 650 52 44 57.5 to 60 Flat (no curvature)
“String spread” means the width between the lowest string and the highest string. This is narrower than the fingerboard width, since there needs to be extra wood on either side so that a string won’t pop off the edge of the fretboard if it’s fingered carelessly or used for the ever-popular pull-off maneuver on the high E string.

String spread at bridge saddle can be narrow if you’re playing with a pick. But if you play fingerstyle, and especially if you are playing an acoustic guitar and you have to dig in with your fingers to get a loud sound, you need wider spacing.

Some classical guitar manufacturers and luthiers permit the customer to order a traditional classical guitar with a wider nut width of 54mm, or a narrower one of 50mm.

Here are some American measurements: a Les Paul has a nut width of 1-11/16”, a Martin fingerstyle has a nut width of 1-3/4”, a parlor is 1-7/8”, and a classical guitar is 2-1/16”.

As a final note, 12-string electric and acoustic guitars usually have a nut width of 45 to 48mm, or 1-3/4” to 1-7/8”. More space is needed for the extra strings to be manipulated by your fingers. Rickenbacker 12-strings are a noteable exception; theirs are very narrow, more like a 6-string Strat.

Play a range of these guitars and you’ll realize that a difference of a couple of millimeters in any width makes a readily discernible difference in how the fingerboard feels, and how easy it is to play intricate fingerings. The question is, what can your hand adapt to? Will you adapt your fingers and technique to fit the guitar, or will you go the extra step of finding a guitar that fits the technique you have already developed? What if you have smaller-than-usual hands? As long as it doesn’t notably interfere with playing the music, it makes sense to me to find a compromise and get the narrowest, most comfortable fingerboard with the most curved radius that works for me.

Here’s the deal: Most models of crossover guitar have a nut width of 48mm, a string spread at the bridge saddle of 60mm, and a fingerboard radius of 380mm to 510mm. Thus they fall neatly between the measurements of a traditional classical guitar and a “fingerstyle” acoustic steel-string guitar. This is wide enough to play classical guitar music, but narrow enough for your average steel-string player to be able to adapt to a classical guitar.

When I went to a classical guitar store and told the proprietor that I wanted a guitar with a narrower fingerboard width and string spacing than standard, she frowned and said, “But you need all of that width to play classical guitar music”. Well, maybe you do, but I can’t get used to it. So for now, I need something that fits my fingers. Maybe in the future I could graduate to a full-width fingerboard, but for now, I need a crossover guitar.