In the first design, the asymmetric fan bracing with the treble bar angled out from the transverse bar below the sound hole is not unlike the design found in many guitars. The focal point for the fan braces falls at the center point of the 10th fret which mitigates in favor of a warm, "open" sonority.

The lower design employs two  focused 7 strut fan bracing systems.  The focal points for these fall approximately at the 2nd fret and out from the center of the fingerboard to a distance approximately equal to the outer edge of the lower bout. 

The asymmetric design produces a sonority similar to that of the old Torres style guitars which I have grown so fond of, along with excellent balance, great clarity and just the right amount of sustain. 

The dual fan design functions somewhat like a lattice system but without the tonal departures from the Torres-like sonority that lattice designs often exhibit. Tonally the two designs are very similar, however, the dual fan system seems to produces a slight increase in treble enhancement which I find very satisfying. 

The top for the dual fan design is somewhat thinner and the total mass of the braces is slightly less than the first design. As a logical result, the dual fan design produces more volume and projection albeit both types reach out very well in a concert hall setting. 

The sides are joined to the neck using a modified approach to the  traditional Spanish way. Both of the upper transverse bars are taken into the linings and a reinforcing pad strengthens the sound hole perimeter.

Two more cross grain pads above the sound hole protect the top from cracking along the edges of the fingerboard. 

The linings are from ash and are laminated, 3 ply for the top and 2 for the back. The transverse bar below the sound hole is quite massive and is made from maple. All of this combines to form a very rigid foundation for the active area of the top. The mass imparted by  the high density ash &  maple coupled with the rigidity of body perimeter  contribute to a desirable level of sustain throughout the full range of bass and treble tones.  

The benefits I was looking for from the elevated fret board  included improved quality in the treble notes above the 12th fret to the extent that they would be more consistent with the notes below the 12th fret. I expected this to result from the continuance of neck wood supporting the fret board all the way to the sound hole. 

I also anticipated having more control over the fret board action again due to consistent fret board support.

Lastly, I anticipated improved playability above the 12th fret based upon the observations made by most players when they experience a raised fingerboard. 

The two most significant examples of a raised fret board design that I know of are the guitars made by Greg Byers and Thomas Humphrey. However, these guitars do not employ the Spanish heel construction architecture and I believe that the Spanish heel architecture produces a number of benefits that I'm not prepared to relinquish. So, in order to achieve my objectives I developed a design 

that incorporates both a raised fret board  and a Spanish heel type architecture. 

My expectations were met by the new design, however, two additional benefits became apparent when the instruments were completed and tested. The new guitars were even louder than the previous design. This may have resulted from the downward slope to the top which results in the strings pulling from a slightly different angle. Another possibility is the top doming wherein the whole top is domed with the apex of the dome located at the mid point of the top. Previously only my lower bouts were domed with the apex of the dome located at the mid point of the saddle. It may also be that both of these factors contributed to increased volume. 

As is common with high quality guitars, I experienced a certain amount of fan brace "imprinting" wherein the location of the fan braces was visible on the face of the tops when they were polished. This imprinting has reduced considerably  and I am quite certain that this is a result of the change in the doming.

The elevated fret board design has proved to be so successful that I now use it exclusively unless I am asked to do otherwise.. 

When complete the top is attached to the neck and then the sides are affixed to both the top and the neck at the same time. The top resonance will change as a result and it is again measured. The top may then be thinned further around the edges to reduce the resonant frequency if necessary.The guitar is now ready to receive the back.  The back braces are a little heavier than usual for additional mass.  

When the back is on, the box is now closed and a cavity resonance can be determined. If adjustments are needed, the back perimeter can be thinned as well as the perimeter of the top if not already done.  If all has gone well, both the top and cavity resonance will be where I want them to be.

Finally I decide upon the weight of the bridge. If the resonance is on the high side of my targets, the bridge may be made a little heavier if lower, it may be lighter. 

Before gluing on the bridge, the bindings and purflings are put in. When the bridge is glued on,  the resonance of both the top and cavity are checked one last time. If, at this point the perimeter of the top still has not been thinned in order to achieve a desired response, there is one last opportunity to do so.

I then fashion the compensated nut and saddle, install the tuners,  string the guitar, adjust the action and play it for a few days until it fully "wakes up". If deemed desirable I may make further adjustments by thinning the top closer to the center, removing wood from the bridge to lighten it etc. When I'm satisfied that the guitar is the best that it can be, I then remove the strings and tuners and  weigh the completed guitar. Finally, I french polish the instrument and the work is done.  

So, to summarize the decision making or "voicing" part of construction process, tapping and feeling are replaced by measuring resonance and stiffness with specific instruments. A laboratory scale is used to calculate density and measure the weights of the braced top and back to ensure that they fall within predetermined parameters. Stiffness and elasticity are measured by placing the top in a special frame and measuring the amount of deflection and return when a specific amount of weight (force) is applied to the top and removed. Resonance is measured by applying variant frequencies to the top with a tone generator until it reaches its maximum vibration amplitude. The top is thinned until the target resonance is achieved.  In order to work this way, one must know what the density, stiffness and resonance targets should be and this is part of what  I learned during the master class with Greg Byers. 

At the completion of each stage of the voicing process using measuring instruments (most of which were not in existence during the time when Torres built guitars) I then "tap and feel" so that my hands also get an education. This is important to me as I believe that the hands can be incredibly sensitive measuring devices and that my tactile senses are becoming "calibrated" in this way. 

Greg also teaches that records should be kept regarding the final measurements for each guitar made along with comments covering a subjective assessment of the guitars characteristics when it has been completed. These records begin to form a collection of empirical data upon which to base further evolution. 

While each of my guitars will differ somewhat in character as a result of unique qualities in the materials making up each instrument,  the overall quality has been very consistent from one to the next.