Luthiers: Scalloped Bracing Question

[chicago12string]

Scalloped bracing on Taylor LKSM-12:





Strung with 13's and rings like a bell.

[aragorn]

Interesting discussion. Neither of my guitars uses scalloped bracing, but the Almansa uses tapered braces while the Raimundo uses straight-sided ones.

The Raimundo has more sustain. Both are well-balanced to my ear.

-brian

[Jim_H]

I'm not an expert by any stretch of the imagination, but it seems to me that tapered (sometimes called parabolic) bracing and scalloped bracing have their places. I don't think I've ever seen anything remotely close to scalloped bracing in a classical guitar.

I would think a small bodied guitar would not benefit much from the scalloping because the braces are shorter, but larger bodied guitars (i.e. dreads and jumbos) would gain more from some looser areas over the long cross braces in particular.

It seems to me that there is not much of an advantage to scalloping shorter finger braces and the like, since they are so short.

The bottom line is, bracing is an art and not a science. There is no right or wrong way to do it. The goal is to make a guitar sound a certain way, while leaving enough strength and stability in the top so the guitar will have a long happy life.

[D.Kwasnycia]

In what has been said about tapered bracing to compare with scalloped bracing? I heard a guy (builder) talking about the flamenco guitars he made and how the flamenco guitar differs to the classical. Tapered bracing =shorter sustain and scalloped bracing = longer sustain.
So from what I have heard some of you are saying ,the subject is the opposite.
I was also under the impression that a finger style guitar needed articulated notes (shorter sustain) and a faster frequency with tapered bracing. Scalloped bracing would give you a longer sustain and longer frequency.

Is it also true that scalloped bracing will give you more projection, since the plucked note is not restricted?

[Howard Klepper]

Originally Posted by cougar2

In what has been said about tapered bracing to compare with scalloped bracing? I heard a guy (builder) talking about the flamenco guitars he made and how the flamenco guitar differs to the classical. Tapered bracing =shorter sustain and scalloped bracing = longer sustain.
So from what I have heard some of you are saying ,the subject is the opposite.
I was also under the impression that a finger style guitar needed articulated notes (shorter sustain) and a faster frequency with tapered bracing. Scalloped bracing would give you a longer sustain and longer frequency.

Is it also true that scalloped bracing will give you more projection, since the plucked note is not restricted?

I am not always sure what people mean by 'tapered' bracing. To me it means the top of the brace defines a more or less straight line, and the height of the brace lessens as it approaches the rim of the guitar.

Other things being equal, scalloped braces will give less sustain than tapered. The top is more flexible, hence more readily set in motion with a greater excursion. The volume of the note rises faster, and, there being only so much energy available from the plucked string, it gets used up faster and the volume falls sooner. This is what a lot of flatpickers desire, and part of the reason why scalloped bracing is favored among bluegrass players. It also tends to be favored by fingerpickers (I'm also often not sure what "fingerstyle' is intended to mean, since it could be so many different styles) who play country blues, or others who want the bass to thump, and the notes just played to get out of the way of those that follow.

[Fran Guidry]

Originally Posted by John Arnold

It all depends on how much the braces are scalloped. A 10% reduction in brace height reduces the stiffness by 27%.
The stiffness of individual tops can vary widely, so the suitability of a certain string gauge should always be determined on a case-by-case basis.
Scalloping loosens the top in the bridge area, while maintaining the stiffness around the edges. The result is more punch, since a smaller area of the top is excited when the string is first plucked.
Scalloped brace guitars generally have a bit less sustain than unscalloped or tapered brace guitars. There are always tradeoffs.

Thank you, Mr. Arnold.

I know the luthiers in this thread know who you are, but perhaps others don't.

If not, please Google "john arnold guitar," "john arnold luthier," and john arnold spruce" to get an idea.

Fran

[66strummer]

Originally Posted by Eugenius

OM's generally use thinner braces, therefore the desired tone might not be great with Scalloped bracing.

I know that the Martin OM-28 uses scalloped bracing while the D-28 doesn't. My Stanford dread has scalloped bracing but the OM does not. Bizarre.

I'll be very interested in hearing your findings with the new Stanford PSOM-10 when it arrives, Eugenius. IMO there is some very serious thought put into their design work. I would be really curious hearing Toni Goetz's input about his bracing techniques......

Ryan

[mmmaak]

Originally Posted by SteveS

I have built both, but prefer parabolic bracing, make that parabolic lattice bracing. The term parabolic is applied in a general sense to indicate that the transition in height is very gradual, but there is no way any one's braces are actually parabolic.

Thank you, Steve. That's exactly what I had suspected all along, but a quick Google didn't turn up the info I was looking for. So, there really is no difference between "parabolic" (as a loosely used term) and scalloped braces?

[SteveS]

Originally Posted by mmmaak

....... So, there really is no difference between "parabolic" (as a loosely used term) and scalloped braces?

There is a difference, both in shape and sound. I like the sound of both, but I like the sound of "parabolic" more.

[mmmaak]

Originally Posted by SteveS

There is a difference, both in shape and sound. I like the sound of both, but I like the sound of "parabolic" more.

Sorry, I must have misunderstood what you posted. So, what exactly is the difference, then? If "parabolic" implies that the "transition in height is very gradual", as you mentioned, then are scalloped braces more "scooped"?

Howard also said "All it means in connection with bracing is 'convex.'" Doesn't that imply both terms, parabolic and scalloped, are pretty much equivalent?

Seems like I'm missing something here

[D.Kwasnycia]

Originally Posted by Howard Klepper

I am not always sure what people mean by 'tapered' bracing. To me it means the top of the brace defines a more or less straight line, and the height of the brace lessens as it approaches the rim of the guitar.

Other things being equal, scalloped braces will give less sustain than tapered. The top is more flexible, hence more readily set in motion with a greater excursion. The volume of the note rises faster, and, there being only so much energy available from the plucked string, it gets used up faster and the volume falls sooner. This is what a lot of flatpickers desire, and part of the reason why scalloped bracing is favored among bluegrass players. It also tends to be favored by fingerpickers (I'm also often not sure what "fingerstyle' is intended to mean, since it could be so many different styles) who play country blues, or others who want the bass to thump, and the notes just played to get out of the way of those that follow.

Thanks Howard,
This makes sense and clears up some things for me. I had somebody trying to convince me of the opposite way around.
Thanks!!

[Piotr]

Originally Posted by mmmaak

Sorry, I must have misunderstood what you posted. So, what exactly is the difference, then? If "parabolic" implies that the "transition in height is very gradual", as you mentioned, then are scalloped braces more "scooped"?

Howard also said "All it means in connection with bracing is 'convex.'" Doesn't that imply both terms, parabolic and scalloped, are pretty much equivalent?

Seems like I'm missing something here

I would call scalloped braces "concave". Could someone post a picture of a typical parabolic setup?

[mmmaak]

Originally Posted by Piotr

I would call scalloped braces "concave". Could someone post a picture of a typical parabolic setup?

I would too, but I'm assuming Howard is talking form the "point of view" of the removed portion

[Pat Foster]

Some examples, if I may.

Scalloped:



What is often referred to as "parabolic", though I would call them "not scalloped" :



Pat

[mmmaak]

Originally Posted by Pat Foster

Some examples, if I may.

Pat

So that's it! I've been thinking about the whole thing backwards (?). "Parabolic" refers to the actual braces, not the shape of their "scallops". No wonder Howard referred to them as convex rather than concave!

Thanks, Pat!