We have felt from the beginning that our new bridge would
be an improvement over the bridges that we were making
and using when we built Gibson and Flatiron mandolins
 at Gibson's Flatiron division. During that time, we noticed
some drawbacks to the Loar-style design and tried to
improve upon them with our new bridge.

Most of the observations listed below were brought to our attention by mandolin players who asked if we could do something to fix them. Although some of the drawbacks of
the Loar-style bridge produce very small effects on sound
and tone, our intention at Sound To Earth is to build the best possible instruments. With that general philosophy, we have tried to remove all of the areas on the bridge and saddle where tone or volume could be corrupted. The following are some of the areas that we addressed with our new design.

 (1)

The Loar-style bridge cannot be adjusted under full  string tension.

Our bridge can be adjusted under full string tension because the adjusting screws are pushing wedges horizontally into
two inclined planes rather than directly up against the full tension of the strings. The mechanical advantage of the screws is greatly enhanced with this arrangement because
the majority of the force from the strings is transmitted directly down into the base, only a fraction of that force is exerted sideways into the adjusting screws.

 (2).      

On a Loar-style bridge, the sound vibrations of the strings
are transmitted from the saddle to the base through brass screws. We believe that the resonant frequencies of the wooden saddle and the brass posts are different and that the difference will induce parasitic harmonics that dampen or change the sound of the instrument. There is also a slight induced vibration from the wooden saddle to the brass posts because the screw holes in the saddle have to be large
enough to allow the saddle to slide up & down. Any vibration between the saddle and the posts will modulate with the
string frequencies and either abnormally enhance or partially reduce particular frequencies.

Finally, all of the string vibrations on the Loar-style bridge must be transmitted through two relatively small pathways. The support screws aren't very big and their vibration, in effect, has to vibrate the whole top of the instrument. We
felt that we would like to have larger contact areas from the saddle to the top of the instrument.

Our bridge transmits the sound directly from the strings, to the saddle, to the wedges, to the base, to the top of the instrument. There is flat wood-to-wood-to-wood contact all
the way down to the top. Since all of the components in the line of transmission are the same material, there is not a problem with different resonance or parasitic frequencies. Vibration is also reduced or eliminated by the fit of the
saddle into the base and because the materials are the same. Since the saddle is enclosed in the base, we believe that the entire base becomes a conduit for transmitting the string frequencies to the top.

(3).      

The Loar-style saddle has a tendency to bow or break in the middle because it is only supported on the ends. This general tendency of the saddle to bow or break in the middle has required that the saddle be a relatively large chunk of ebony with no internal defects. We always felt that the size of the saddle and the placement of the support screws on the ends dampened the harmonics of the middle strings. And of
course, a mandolin with the middle strings lower than the outside strings is hard for anyone to play well.

On our new design, the saddle is relatively thin and small
with the widest part of the saddle directly under the center
of the strings. The wedges that support the saddle are also located directly under the strings. Since the saddle is only 1/8" thick, flaws in the wood are easily seen before it is
used. After three years of production and over 1000 instruments sold, we have never had a complaint about a broken or bowed saddle.

(4).      

We noticed and had customers inform us that the saddle
often leaned toward the nut line of the instrument. This tendency to lean affects the scale length and intonation as string tension is increased. In essence, as you tighten the strings to tune them, the saddle can be pulled closer to the nut; especially if the saddle is at the high end of its
adjustment range from the base and the screw post holes
are too large. There are several elements in the basic
design of the Loar-style bridge that contributes to the lean
of the bridge and of course, improper installation of the
base can also increase the lean of the bridge.

(a).       The saddle will always be at a slight angle to the
base because the knurled nuts that support the saddle are
at the angle of the supporting screw threads. The lean of the saddle will be increased if the saddle is at the higher end of
its range, where the support screws can flex (more common
on mandolas and octaves), or if the holes in the saddle
around the screw are loose.

(b).       The saddle support screws have the potential to induce several problems. If they are not parallel to each
other and vertical to the base and top, in all directions, they may accent the lean and change the intonation as the bridge
is raised or lowered. If one screw leans forward, toward the nut, and the other leans back, away from the nut, the combined error will rotate the saddle slightly as it moves
up the screws and this will affect the compensation of the saddle. If they are leaning away from each other, in any direction, the surface contact area between the saddle and
the knurled nut will be reduced and the sound of the instrument will be affected.

Our bridge base supports the saddle completely on all sides. The saddle is always held in a stable, vertical position in relation to the bottom of the base. The saddle cannot twist
or rotate as the height is adjusted and the compensation of
the saddle will not change. 

When an instrument is strung for the first time, the top and bottom strings should be tightened first and then the bridge base should be pushed down to insure that it has full contact with the top. Then the other strings should be installed.

Although, the entire bridge assembly may still lean toward
the nut slightly as string tension is increased the lean can
be reduced by insuring that the bridge is fitted to the top correctly and by following the procedure above when
installing the bridge.