Tight tops with visible X bracing

[ALBD]

How many of you can see the X bracing warping your top just above the bridge? I have a couple of guitars made by two different and well regarded luthiers that have this trait (I live on the NC coast and keep the guitars in humidity controlled cases—they are not dry guitars). The X bracing is clearly visible at certain angles.

Both luthiers independently indicated that this is by design and is the mark of a top that has been pushed to its sonic limit. One anecdotal story was that Ervin Somogyi designs his guitars so that the tops are on the brink of explosion in order to maximize its sonic potential. Both of these guitars are, in fact, unbelievably responsive to a light touch, but hold up to a pick. I’m curious how many of you have similar experience. Thx.

[jonfields45]

If you are looking at shallow angle reflected light to detect the bracing, you will be able to easily see very small variation 100s of times less than the thickness of the top. If you look for it I think this is more common than you might expect and even with factory guitars.

[jaan]

I had a Gibson L00 that had visible X braces. It’s sounded great and never bothered me in any way.

[charles Tauber]

Originally Posted by ALBD

Both luthiers independently indicated that this is by design and is the mark of a top that has been pushed to its sonic limit.

It is probably fair to say that no luthier purposely designs a guitar so that the braces telegraph through the top. What they do is design a "lightly built" guitar a consequence of which is that one can often see the bracing telegraphing through the top. This is very common in classical guitar fan bracing but is not uncommon in steel string guitars.

One needs to be careful of the distinction between causation and correlation. Simply making a guitar "lightly built" does not guarantee it has a superior sound. Put another way, the ability to see bracing telegraph through the top doesn't guarantee that instrument will have a superior sound. By contrast, on many superior-sounding guitars one can see the bracing telegraphing through the top.

[ALBD]

Originally Posted by charles Tauber

It is probably fair to say that no luthier purposely designs a guitar so that the braces telegraph through the top. What they do is design a "lightly built" guitar a consequence of which is that one can often see the bracing telegraphing through the top. This is very common in classical guitar fan bracing but is not uncommon in steel string guitars.

One needs to be careful of the distinction between causation and correlation. Simply making a guitar "lightly built" does not guarantee it has a superior sound. Put another way, the ability to see bracing telegraph through the top doesn't guarantee that instrument will have a superior sound. By contrast, on many superior-sounding guitars one can see the bracing telegraphing through the top.

This is a good clarification. I was not told that the look was by design. It would have been better stated that the telegraphing is a result of the light build.

[brandall10]

It's not hard to see on my OM-28A, you can even see the outline of the heel block when light hits it at the right angle. The top is super thin.

[jazzguy]

Related question - when one refers to a “lightly built” guitar, are we primarily talking about the top and top bracing, or the entire guitar?

[ALBD]

Originally Posted by jazzguy

Related question - when one refers to a “lightly built” guitar, are we primarily talking about the top and top bracing, or the entire guitar?

Here is a video I just stumbled on from Somogyi. Go to the 6 minute mark. It seems that it’s a very selective process that entails more than just the top.

https://m.youtube.com/watch?v=d6DQ6JfVT44

[charles Tauber]

Originally Posted by jazzguy

Related question - when one refers to a “lightly built” guitar, are we primarily talking about the top and top bracing, or the entire guitar?

Can be either: it is a very general term. It can refer to weight (mass) as well as stiffness. For example, one can have a light-weight guitar that is too stiff or a heavy guitar that isn't stiff enough.

Neck blocks can be large and heavy, as can be tail blocks. Or they can be much lighter. A tail block, for example, can be made from a single, larger piece of wood, it's strength coming, in part, from its size. It can also be made from multiple thinner layers of wood, the sum of which is much smaller and lighter than the single larger block. (The ply will be stronger than the larger single piece, but weigh less.)

Linings between sides and top/back can be solid wood, kerfed, reverse-kerfed, etc, each lending different weight/stiffness ratios.

There are "live" backs and "passive" backs. Live backs are intended to be "lively" and are thinner and braced less/lighter weight.

Necks can be physically heavy - laminates of maple, rosewood or other hard wood - versus physically lighter, such as mahogany or Spanish cedar. Reinforcement rods can be heavier or lighter depending upon whether or not they are adjustable and the design employed.

Michael Kasha espoused a design in which a weight was embedded into the head to add "inertia" so that vibration isn't "wasted" in the neck, and used a heavy steel "H" between the neck and body to help isolate the neck: weights were then added to the tail block to physically counterbalance the instrument.

In short, the term "lightly built" can mean much of whatever you want. Usually, it means that components have the minimal amount of material to withstand the forces imposed on them, the goal being to produce as responsive an instrument as possible. Some of that has to do with how the materials are used and in what geometric configuration.

One can build a guitar like a log cabin, but it won't sound very good. One can also build a very good sounding instrument that won't last more than a year or two before string tension destroys it. The balance is to have one that is good sounding but of sufficient longevity. No maker wants to have to replace a guitar in two years under warranty because, while it sounded great, it fell apart.

At its simplest, the guitar is a mechanical system, the response of which is dependent upon mass, stiffness and damping. Generally, mass promotes bass frequencies, stiffness promotes higher frequencies and damping reduces output. One attempts to balance mass and stiffness while providing sufficient structure that the guitar doesn't come apart under prolonged string tension. There are many, many ways to accomplish that balance, with each maker using his or her own preferred approach to achieve his or her preferred response. There isn't a single "target" response that everyone agrees sounds "good".

[Wade Hampton]

Back in the 1970’s, Gibson achieved terrible results when they start using a glue curing process that made the top bracing start showing through the guitar top after the instrument was seven or eight months old. This coincided with the introduction of Gibson’s much-hyped “Mark Series” guitars, but wasn’t limited to only those guitars. I can remember seeing a Hummingbird that looked like Skeletor, with all the braces visible through its bright red and yellow sunburst.

It wasn’t the most attractive look I’ve ever seen, let’s leave it at that...


Wade Hampton Miller

[jazzguy]

Originally Posted by charles Tauber

Can be either: it is a very general term. It can refer to weight (mass) as well as stiffness. For example, one can have a light-weight guitar that is too stiff or a heavy guitar that isn't stiff enough.

Neck blocks can be large and heavy, as can be tail blocks. Or they can be much lighter. A tail block, for example, can be made from a single, larger piece of wood, it's strength coming, in part, from its size. It can also be made from multiple thinner layers of wood, the sum of which is much smaller and lighter than the single larger block. (The ply will be stronger than the larger single piece, but weigh less.)

Linings between sides and top/back can be solid wood, kerfed, reverse-kerfed, etc, each lending different weight/stiffness ratios.

There are "live" backs and "passive" backs. Live backs are intended to be "lively" and are thinner and braced less/lighter weight.

Necks can be physically heavy - laminates of maple, rosewood or other hard wood - versus physically lighter, such as mahogany or Spanish cedar. Reinforcement rods can be heavier or lighter depending upon whether or not they are adjustable and the design employed.

Michael Kasha espoused a design in which a weight was embedded into the head to add "inertia" so that vibration isn't "wasted" in the neck, and used a heavy steel "H" between the neck and body to help isolate the neck: weights were then added to the tail block to physically counterbalance the instrument.

In short, the term "lightly built" can mean much of whatever you want. Usually, it means that components have the minimal amount of material to withstand the forces imposed on them, the goal being to produce as responsive an instrument as possible. Some of that has to do with how the materials are used and in what geometric configuration.

One can build a guitar like a log cabin, but it won't sound very good. One can also build a very good sounding instrument that won't last more than a year or two before string tension destroys it. The balance is to have one that is good sounding but of sufficient longevity. No maker wants to have to replace a guitar in two years under warranty because, while it sounded great, it fell apart.

At its simplest, the guitar is a mechanical system, the response of which is dependent upon mass, stiffness and damping. Generally, mass promotes bass frequencies, stiffness promotes higher frequencies and damping reduces output. One attempts to balance mass and stiffness while providing sufficient structure that the guitar doesn't come apart under prolonged string tension. There are many, many ways to accomplish that balance, with each maker using his or her own preferred approach to achieve his or her preferred response. There isn't a single "target" response that everyone agrees sounds "good".

Thank you for the very thorough explanation.