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Regarding
Solid Body Stringed Instrument Addressing Sonic Production, Deadspots
and Such:
Since the first
Carbon-Graphite neck beams were produced there has been much discussion
about the ability of C/F necks to diminish or eliminate the less attenuated
or harmonically complete notes known as deadspots. These more commonly
occur on wood-necked stringed instruments. The claim that C/F necks eliminate
all deadspots in all cases was most-widely made by Modulus Guitars. Even
though it is generally the case, such a comprehensive claim has never
been made by Moses Carbon Graphite for reasons that actually apply to
all carbon graphite necks. Whereas, Carbon Graphite necks do have the
ability to eliminate deadspots, this generalized and comprehensive statement
was and remains untrue in various cases. This is due to the actual and
real complexity of stringed instrument materials, material relationships
and construction. In a stringed musical instrument, all materials between
the nut and the bridge saddles contribute to the movement of string-activated
sonic information. In some cases material composition and embodiment even
beyond this area effect attack, sustain and decay along with the notes
frequency content as the note plays-out. When a Carbon Graphite neck beam
is properly produced, and is continuous between the nut and the bridge
as with a neck-though-body beam, the producer of the beam has complete
control over all material composition. In this case the manufacturer designs
the entire active beam, thus dictating all aspects of outcome with respect
to a notes tone, development and attenuation. And in this case,
a properly engineered and well-constructed C/F neck through body beam
can be manufactured to comprehensively eliminate all deadspots. Conversely,
when the neck beam is not continuous from nut to bridge, the design engineer
looses complete control of the outcome due to the introduction of other
variables, especially within the vibrating string length system. Neck
and body discontinuity, known as de-coupling, results from use of a bolt-on
neck beam and leaves the neck as but one major yet separated
element amongst a group of nut to bridge parts. As general background,
it is important to note that Carbon fiber is used in various embodiments
to produce neck beams. Basically, not all C/F necks are made in the same
way, nor with the same set of materials. Including and in addition to
the disparate physical embodiments, and the resultant differences between
bolt-on and neck through beams, there are a number of other elements,
all working in combination. These interact with each other to produce
a complex variety of results. Individual elements and element combinations
that effect outcome include:1) Relative density of each element. For instance,
neck beams or bodies may have a density or combination of densities which
produce a resonant frequency or a group of frequencies that absorb energy,
thus producing overall attentuation and cancellations.2) Separate neck
and body beams may each have discrete overall densities which combine
together with varying degrees of success relative to even
and complete transmission of energy between the nut and bridge. A wood
or Carbon Graphite neck beam may tend to work very well in most cases
with a specific body material type. However, even another piece of wood
from the same tree may react differently when mounted on the same body
after becoming a finished neck. Specifically and by example, acoustic
luthiers pride themselves on their selection of specific pieces of particular
woods in order to achieve their perceived best result. Often players of
electric stringed instruments simply purchase their instrument with limited
or without any examination of even the surface of the body material, let
alone its interior quantities. If they even know what the woods
species is, they may be assuming that all pieces of a perceived good specie
are the same and good for its application. This is not simply true. Specifically,
when water is scarce, a tree grows more slowly as exhibited in its yearly
growth rings, making the wood very dense relative to its particular norm
and resulting in a different composition of elements than during the wet
periods. The dark 'rings' are the dense slow growth periods, with the
fat light regions the fast growth periods). The knots where tree limbs
formed also have slightly different characteristics in composition and
density . The bottom line is that within one wooden log are sections which
have different percentages of each element. This variation in composition
means that not all sections of that wood beam will exhibit the same characteristics.
a) Woods have disparate densities within and between its major fibrous
grain and other cellulousic material.b) Woods have various and varying
distribution, orientation and density of fibrous grain.c) The actual
overall density and distribution of densities within a particular
piece of wood often varies from Textbook for that Species.
These characteristics also vary greatly within adjoining areas of each
piece of wood. Thus it can only be accurately stated that a particular
wood has a tendency to provide a specific outcome. A piece
of wood is generally chosen by looking at the surface, tap-tone testing,
choosing a specific orientation in use, etc. The piece is tooled to remove
material in order to achieve the target dimensions. This process, taking
away material that you dont want until you have left what you do
want, is subtractive. With good fortune its contribution
to the instrument will be what is desired. In contrast, the production
of a Carbon Graphite neck beam is additive. C/F necks are
not made from a solid lump of stuff, but are engineered to produce specific
outcomes. The design engineer chooses a group of materials which when
combined, produce a calculated result. In the C/F case, the designer has
much greater control over the outcome. This is the result of purposeful
choices made which are based on study of the complex relationships of
selected composite materials. Other key elements effecting outcome include:1)
The material composition of a headstock. Some absorb energy while others
do not. When headless necks were introduced, its exclusion removed this
variable from the equation while shifting nodes to new locations along
the beam.2) As stated above, neck through body beams, which are continuous
from nut to bridge, maintain relative continuity of materials between
these key points. A wood neck through beam may still contain unpredictable
variables within. In contrast, an engineered Carbon Graphite neck through
beam can be designed and constructed to minimize or eliminate the unknown
internal variables inherent with wood. Thus, the outcome becomes far more
predictable. However, when a wood or Carbon Graphite neck beam is bolted
onto a separate body, this introduces a notable discontinuity where the
neck heel sets against the body in the heel pocket. Even though an installer
may firmly mount the neck so that string tension is fully held, there
is no mating of the adjoining surfaces on a molecular level.
In essence, two surfaces pushed against each other still have microscopic
(and larger) gaps between adjoining surfaces. These spaces are barriers
to complete transfer of energy. In many cases, the energy transfer when
compared to continuous beams may be circa 50%. Sadowsky Guitars and others
have taken to applying an Epoxy coating to the necks heel, with
the bolt-on neck isolated from the body pocket with an intermediate and
temporary separation layer of Saran Wrap or mold release. This is an attempt
to produce a body pocket surface that more closely reflects the shape
of and mates to the bottom of that removable necks heel. It should
be noted that energy lost as it attempts to cross discontinuities is not
all of the same frequency or the same group of frequencies, nor is there
the necessarily the same amount of attentuation across the frequencies
included. So at each point of discontinuity, the relationship
of frequencies that continue to travel through the neck/body system changes.
This dynamic of change is occurring multiple times between the nut and
the bridge ( and beyond) for each note generated; A becomes
A +/- B; A +/- B becomes {A +/- B} +/- C,
etc. With woods it is well-known that close, tight and continuous strand
fiber is required to produce the optimum structural and tonal results.
In its own way, the same is true with carbon fiber. When both wood and
Carbon Graphite necks are bolt-on mounted, the continuous strand embodiment
and thus the material continuity between the beam and the body is severed.
As a notable aside, neck through body beams contribute greater sustain
relative to attack than do bolt-on beams.3) A mounted nuts mating
to the surfaces of the nut slot as well as the degree to which the string
mates with the individual nut string slots has a similar influence as
that discussed in #2. As pertains to the strings mating, simply imagine
the amount of surface contact that can be lost when a string does not
sit so that the bottom and sides are completely in contact with the nut
slot walls. And to a degree, the kind of isolation of a vibrating roundwound
string, which has less string surface touching the nut slot walls, produces
different results than a flat wound string having more material leaning
on the nut slot surfaces. However, there is overall a different set of
dynamics happening due to the stopping of the string at each halftone
position up the neck, the dynamics of a string vibrating in atmosphere
above the board, material composition, string dimensions, mass and other
factors.4) Cancellation through the bridge and nut to the neck beam and
body (or potentially even an increase in amplitude) when one string remains
vibrating as another string is activated is a factor.5) The mounting of
and material construction of the bridge influences the outcome. Moses
C/F has found instruments with mounted bridges that, although holding
string tension, were mounted with gaps left between their base plate and
the body beneath. This space reaps similar results to that of a poor neck
to heel pocket connection. Even a solidly set bridge is basically resting
on the surface of the body, thus remaining discontinuous as an element
as well as generally different in material composition and density.6)
The mating of the sub components constituting the bridge itself have a
tremendous impact on outcome. In essence, each individual part of a bridge
is leaning against the other parts. Every time vibration moves from one
sub component to another across these discontinuities, energy is lost.
We have found that the better the machining of the individual bridge elements,
the better the outcome. But essentially, from the point-of-view of energy
transfer, the fewer the individual bridge sub components, the less the
loss. One solution is to choose a bridge with the minimum number of separate
parts that still satisfies the instrument and players requirements.7)
Strings that are anchored at back of the body (string through) not only
change the strings tension and focus, but often increase the mating
of the string to the body. A a note decays, the material composition of
the neck influences the set of frequencies which continue to sustain.
Some woods neck, notably loose the higher frequencies as they play-out,
so that during the later stages of decay, they are indistinct muddled
and woofy. All of these complexities are exacerbated by the fact that
a neck or other components with one averaged set of desirable
qualities may work well with another specific part, such as a body. And
yet the same neck and body may not match-up with an alternate set of good
quality components. This is technically true. It is also perpetuated
by the perception that a group of individual good parts necessarily dictates
an excellent outcome. This is most often the case. But although the old
saying goes the whole is greater than the sum of the parts,
it was never intended to mean that greater is better or worse. Greater
is simply different in a larger way. So, as this pertains to necks and
bodies, the qualities of an excellent quality neck may and generally does
improve the outcome of an instrument. However, the averaged qualities
of that neck may not match-up with the sum of the qualities of all other
instrument components, especially the unique characteristics of each individual
piece of wood. Overall, as a note decays the material composition of the
neck influences the set of frequencies which continue to sustain. Notably,
most wood necks loose the higher frequencies as they play-out, so that
during the later stages of decay, they are indistinct muddled and woofy.
In other cases, the fundamental falls away, leaving curious sets of upper
frequencies. A properly designed and well-crafted Carbon Graphite neck,
mounted on a compatible body and complete with quality hardware and electronics,
will provide sustainful musical notes with complete harmonic overtone
series throughout their duration. So, the de-coupled mating of a
wood neck or body with a Carbon Graphite neck or body usually does result
in the elimination of deadspots. However, in some unusual instances deadspots
may be only decreased, may move or in rare instances may increase. In
these later and rare cases, it does not mean that the other attributes
of Carbon Graphite necks are not worthwhile. Carbon Graphite necks always
offer great stability with focused clarity throughout an instruments
full range of function, and do eliminate deadspots in the vast majority
of cases.
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