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There are straight braces and scalloped and tapered but what is a brace that is curved from one end to the other and what would the effect be on the sound of the guitar?

Airfoil shape or as Lowden calls them Dolphin shape --- Lowden's are fine sounding guitars. There are a zillion guitars with a zillion different shaped braces. You can put holes in them, add some carbon fiber, shape them like bridge trusses, have flying buttresses, thin fan braces, ladder braces, wide braces, tall braces, laminated braces -- point is its the flex of the diaphragm (sound board assembly) and how it reacts to the string tension that produces the guitar sound -- shape of the braces is small element in the big picture.

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Ken Cierp

http://www.kennethmichaelguitars.com/

I thought an airfoil was perpendicular to the grain. What Im asking about is the lengthwise shape. Could someone talk a little about Dolphin shape?

Yes I know that.

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Ken Cierp

http://www.kennethmichaelguitars.com/

Thanks,
Great drawing.
I thought the top was the most important sound producer but the bracing influences the character of that sound. In my experience straight braces produce a tighter sound and scalloped a deeper sound. Ive never played tapered but Ive read they sound good. I have never played a guitar with braces like Kens drawing.
So Im wondering what change would airfoil/dolphin braces have given the same height, width and perpendicular profile?
Certainly each element of a design must make a difference.

Is it that the shape is not important that Im getting little comments and lots of reads or is it not something our community has experience with? I really thought everything was known on this board.

As far as a name, I saw reference to a similar shape used by Hauser on classicals as "parabolic", though I doubt that it is really was parabolic. I have to defer to others on the effect, but I have read any number of places that it is the entire system that matters. Going back to the name of a shape, too many people make up all kinds of different names to be able to pin it down to a valid name.

I searched Hauser but those are fan braces and that doesnt seem relevant to steelstrings or any major braces for that matter. I then googled parabolic bracing and I found this conversation with some talk about the effect of different bracing shapes by a guy named Scott that was interesting towards the end of the thread.

Generally speaking the brace profile helps to shape the timbre. 'Tapered' bracing, that is taller in the middle and lower at the edges, tends to give more sustain and less bass and power, while 'scalloped' bracing, which is lower in the middle and has peaks further out, goes the other way, with more punch and bass, but less sustain. 'Straight' bracing falls in between.

There are all sorts of variations on the themes, and they all work for somebody. I'm of the opinion that you get the 'best' sound of whatever type when you get a certain 'balance' between the bracing and the top, and this will be different for every set of wood. Knowing how to get that for the brace system you're using is what makes the difference between different makers.

Of course, there's also a certain amount of what could be called 'religion' involved. Let's emulate the Founding Fathers and not go there....