Construction & Bracing Design
Placing five fan braces under the bridge is an excellent way to resist string tension, and in fact it's all the bracing a guitar really needs, even with a thin top. Most, not all, fan braced guitars since Torres will exhibit at least those five braces under the bridge, but with myriad other variations and combinations of bridge patches, outer fan braces, closing V bars, asymmetrical elements, and angle of the braces. I consider those center five braces to be the core element of fan bracing design, and you can get an extremely lively Flamenco guitar by adding nothing else whatsoever, but it takes the right piece of wood to pull it off so that the basses are not overpowering. The guitar on the left was built with a spruce top that happened to be amazingly stiff in the cross-grain direction. It also had very low density and I knew it would be extremely powerful if I got out of its way as much as possible, and it was. It had the same cross-grain stiffness as a normal top would with the bracing shown in the middle picture, and it was much lighter.
The middle picture is a design I have used many times, and is based on some guitars by Barbero, Hernandez y Aguado, and others. The steep closing struts are added to control the outer edges of the top. This makes a guitar that is loud and percussive, and excellent for traditional Flamenco and unamplified dance accompaniment. I've built this design enough to know how to balance that raspiness and depth in the bass-midrange with strong and sweet trebles. In the picture on the right, a patch is added under the bridge with the fan braces notched over it. That way the bridge sits directly over an area with a lot of cross grain stiffness while the rest of the top vibrates more freely. This can make for a very expressive guitar with clear trebles.
This is the bracing pattern I currently use on my Flamenco guitars. I developed it out of a search for a guitar that was 100% Flamenco, but had the complexity, depth and color needed for modern solo playing and recording. Another requirement in developing this design was a very comfortable right hand feel, with the strings having just the right amount of bounce to accomodate Flamenco technique. I actually believe that these guitars tend to be less buzzy than my previous guitars because the top vibration is more controlled. This allows the action to be slightly lower and makes for a guitar that is a bit easier to play overall.
There's nothing particularly wild or revolutionary about this layout of braces, but I've brought some different elements together in a way that is definitely my own. The center 5 braces are parallel, which is fairly uncommon, but found more frequently in the work of some of the makers in the Domingo Esteso-Conde Hermanos lineage. The lack of cross-grain stiffness this creates in line with the bridge tie block I believe contributes to that approachable right hand feel. The high closing V bars give me more control over stiffening the area of the bridge wings and the outer, angled fan braces provide more control over the edge of the top. Other equally important elements in top design are 1) The bridge, which is always between 14-16 grams on my Flamencos, 2) The thickness and graduation of the top, which varies depending on the stiffness of the wood, and 3) the doming of the top.
This is the bracing pattern I use on my Classical guitars and the results have been so good I haven't felt the need to deviate from it much. It was taught to me by Richard Cogger and it's based on Jeffrey Elliott's version of a Hauser guitar, with open harmonic bars. Here the braces are more widely fanned and a patch helps stiffen the bridge area, both elements typical of Classical guitars. I make the top significantly thicker on a Classical than I do on my Flamencos. The guitars are unbelievably expressive and full of harmonics and sustain that way, and I've never sacrificed any low end response, volume, or projection. This design is sheer magic to me.
You will notice on all my guitars that I use full cross-grain side reinforcements in the lower bout, and sometimes the upper bout as well. This is a very lightweight way to greatly improve protection against cracks, which can quickly run the length of an unreinforced side. I also think the added stiffness and stability in the lower bout area causes less of the top's vibrating energy to be dissipated into the sides, making for more volume and sustain.