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A few weeks ago I made a comment in a thread about where and how to place a fretboard on the body of a guitar. I suggested he place the 12th or the 14th fret at the body join and figure out where the bridge will be located.

A fellow member here politely replied that a neck join at the 12th or 14th fret was not actually a hard rule and could be at any fret. I didn't disagree with his statement and figured he knew more that I do about it. But from my experience most guitars are on those frets.


Well... This got me thinking about that and why it is that most guitars have the 12th or 14th fret at the body. I understand that by going with the 14th fret it give you more real estate up the fretboard but that doesn't seem to explain why we have "mostly" setteled on those positions.

I am wondering if this has more to do with the vibrations of the strings and how that interacts with the guitar body and the neck. Or is it a function of structure keeping the joint aproximately near the center of the strings force.


I would be interested in hearing from any of you who have experience. Is there a tone difference in where you place the neck joint. All the 12 fret guitars I have dealt with were all shorter scale or had ladder bracing so that effects the tone of the guitar already.


Thanks for any info you may have about this,

Cheers,
Bob

I have done 12, 13 and 14 fret joins. The 12 frets were for Martin short scale and traditional - i.e. 0-16NY style, etc. Typical sweet mids with not a huge bass response.

A 000 style 13 fret in Martin long scale was done to help with access while still putting the bridge more towards what I thought was the sweet spot on the soundboard. 13 frets still lets you catch a D triad at the 10th fret which is tough on a 12-fret join. I did not hear any real difference in this one over a 14 fret long scale. I did not like this guitar and it has nothing to do with the 13 or 14 fret, I just didn't like the sound so I cut the top off. One of my earlier guitars and it just wasn't voiced well. It's going to become a 14 fret in it's new life.

Then I did a 13-fret Multi-scale (25.15T - 25.4B) This is my current guitar and does not have a cutaway. It's the best sounding guitar I've made to date and it's the one I use for performing. I think the main reason it sounds so good is because I'm finally doing a decent job voicing the soundboards. As a player I don't like the limits on the upper fret access. Next one for myself will be a standard 14 fret with a cutaway,

Have fun and play with it. I think where you put the fret join does make a difference, both in sound and playability. Basically you're moving the bridge back and forth on the soundboard although not very far. Really most anything you do structurally will make a sound difference to some degree. I think other things like body size/shape and soundboard type/voicing are more important. Just my opinion.

My only advice is to keep in mind how it's going to be played as you plan the layout.

_________________
Steve Smith
"Music is what feelings sound like"

RusRob asked:
"I am wondering if this has more to do with the vibrations of the strings and how that interacts with the guitar body and the neck. Or is it a function of structure keeping the joint approximately near the center of the strings force."

Well, in point of fact, what you get in the middle of the string is a lot of motion. The place to read off the force of the vibration is the end of the string, at the bridge.

Joining at the 12th fret makes it easy to find the octave when you're playing; you don't even need a dot. That's probably why they used that as standard on guitars until Martin came up with the OM. That was done, so far as I can tell, to give banjo players a bit more fretboard. They chopped off the standard 12-fret body about two frets up: enough to be useful but not so much as to compromise tone or structure much.

After that I suspect the 'precedence effect' took hold; somebody had gotten away with doing it like that, so it was easier for the next guy to follow along. Once folks got used to playing 14 fret necks anything else seemed 'weird', or, at least, took some further getting used to.

Gibson made a 13 fret Nick Lucas in 1929 but I read that it didn't sell well and they dropped it. Paul Hostetter worked with Santa Cruz to revive a version but I don't believe it was immediately well received, but the H13 is now one if their more popular models. I made a 13 fret l-00 15 years ago but screwed up and put the side dots on the 13th fret. I don't look at side dots so I didn't even noticed until a friend played it.

Kent

I have made a couple of 13 frets and really like them. To my mind the main difference is that a 12 or 13 or 14 fret join (assuming the same scale length each time, and the same body size) will vary the position of the bridge, and also require forward/backward shifting of the bracing to keep it in the same relationship to the bridge. This changes the performance of the soundboard to some degree. Having said that, some of the Martin 12 fret models differ from their 14 fret counterparts by having a longer body where the upper bout is “stretched up” towards the higher neck join and it is not all achieved by moving the bridge further away. Here is a 000-15M (14 fret) and a 000-15 (12 fret).

Mark Mc wrote:
" ....some of the Martin 12 fret models differ from their 14 fret counterparts by having a longer body where the upper bout is “stretched up” towards the higher neck join and it is not all achieved by moving the bridge further away."

My understanding is that they simply chopped off the upper two frets worth of the box to convert a 12-fret to a 14 fret. That's why the upper end is simply flat on the 14 fretters. This shows very clearly in the photos you've posted.

Yes, Alan has expressed it in the right historical sequence. Prior to the 1930 12 frets was the norm and then 14 fretters came into fashion. Martin made the transition mostly by shortening the body and lengthening the neck, while Gibson kept much the same body but lengthened the neck and shifted the bridge.

The important thing to see here is that the bridge location relative to the wide point of the lower bout was not moved by the change on Martins, so that can't be the key to the sound change. What did change was the length of the box, and the relative position of the hole vis a vis the upper edge. Both of those can alter the tone.

Somogyi points out that on a Classical guitar the lower bout is bounded by a fairly stiff cross brace at the waist, so the bridge falls reasonably close to the 'center' of the bout. X-bracing doesn't use that brace, so the upper edge of the vibrating area is shifted closer to the UTB above the sound hole. In theory this shifts the 'center' of the top upward toward the waist on [u]all]/u] X-braced guitars. In practice the change is not all the great: the waist bar on a Classical is not nearly as 'rigid' as the edge of the top, and the upper bout on a steel string is still more rigid than the lower bout. On both sorts of guitars the vibrating area of the loudspeaker-like 'main top' mode extends upward for some distance, although it's usually shifted upward slightly more on X-braced tops that I've seen.

In fact, the 'sweet spot' for the bridge to drive the top depends largely on the way the top is braced and the bracing profiles. It tends to be more or less centered, but can be shifted a fair distance without loss of sound by careful brace design.

At any rate, by that reasoning the 'sweet spot' for banjos 'should' be right in the middle of the round, unbraced, and uniform top. Do banjos commonly have the bridge in the middle? I don't think I've ever seen one like that.

I have built a number of 13 fret steel string guitars like the one in this thread:

viewtopic.php?f=10101&t=55323&hilit=13+fret

It’s a design I’m going to keep on using and tweaking for a while. It’s not a faithful copy of a traditional design, but it is reminiscent of older guitars. I like where everything sits on the guitar, and it fits in a standard dred case. The ones I have built so far sound pretty good, too.

While I would not dream of offering a correction to Mr. Carruth's third post re: matters of primary importance, I would offer an additional consideration for those building for our ever aging population of Boomers and early Gen X'ers. Shortening the neck relative to the location where the guitar rests on the right leg (for righted-handed players) reduces the tension and related stress during play with first position chord shapes, etc. This can be easily experienced with a 14 fret-to-body guitar and a few minutes playing the same piece open and in Capo2 or Capo3. Particularly for those adjacent to or perhaps actually enjoying their seventh decade extant, the bio-mechanical benefits of a shorter 12 fret neck - often paired with a shorter 14 fret body style, shorter scale length, and a cutaway for upper fret access - may keep a customer comfortably in the game for years longer than soldiering on with long-scale 14 fretters.

When I was spending more time in Maryland, we or students built several combinations of what Martin monikered the Norman Blake guitar, (000-14 fret body, short-scale, 12 fret-to-body neck) with variations in 0000/grand auditorium, 00-14, and J-45 - all with Venetian cutaway, shorter scale length, and solid/paddle head-stock. I found the 0000 and 00 variants were the most comfortable for me and with light or extra-light gauge strings, an excellent solution for aging players or those recovering from various hand or wrist surgeries (e.g., carpal tunnel; Dupuytren's Contracture).

Good point Woodie.

One of my students made a 14-fret OM body with a 12-fret neck, a few years back. It sounds fine, and is indeed very easy on the player.

I'm all for considering ergonomics, especially for aging players. I'm sure even a small reduction in reach can have a big difference. This is not to contradict what Woodie and Alan have said above, but to demonstrate how strong the effect can be. Going to a 12 fret neck on a body "intended" to have a 14 fret neck, is shortening by the distance of the 12th to 14th fret, which is much smaller than the difference from the nut to a capo on the second fret. Yet this smaller distance still can have a profound effect on how a guitar feels. We often ask about how changes effect tone and sometimes overlook ergonomics and playability. The first "parlor" guitar I made was for a fund raiser at our cancer center. I reasoned that someone who was going through treatments would appreciate not having to hold and reach around a large box. I was a bit surprised to learn that every time I mentioned that to someone, it got no response and instead a question of if it was going to be quiet or lack bass.

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Bryan Bear PMoMC

Take care of your feet, and your feet will take care of you.

Very good point, Woodie and Bryan. The ergonomics of a guitar are a much under-appreciated and little discussed topic.

Off topic a bit but just a comment for aging players with carpal tunnel, arthritis and so on. I'm 74 and have arthritis in my left thumb and have had surgeries for carpal tunnel (2) and trigger finger. I play a lot - at least an hour a day, more on rehearsal/performance days. Yesterday was 5 hours on stage for rehearsal and performance, no problems getting through it. I play the 13-fret 000 that I referenced above. What makes the difference for me is a very good setup, 11-52 Elixers and I use a strap on the guitar. I sometimes wear a brace on my left thumb, that's where the arthritis is the worst. When using the strap the neck is angled up somewhat like a classical position and lets me get my hand in a more natural position. Anyway, just some thoughts, maybe helpful to someone. You can see in the photo how the strap makes a big difference in playing position - at least for me.

_________________
Steve Smith
"Music is what feelings sound like"

That sounds like you're writing an ad for my guitars, Woodie! Thank you!



This is a 000 sized guitar, 12 fret neck, Venetian cutaway, straight pull head stock (which you can't see) which makes the strings feel lower tension, and in particular, the high waist which brings all the left hand work closer to the body when the guitar is rested on the left thigh. Same for the 00 sized guitar. And they sound good too! (Bruce Matiske playing).

Full plans and build instructions for the 000 sized guitar are in the book.

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Trevor Gore, Luthier. Australian hand made acoustic guitars, classical guitars; custom guitar design and build; guitar design instruction.

http://www.goreguitars.com.au

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Say what you do, Do what you say.