Note: Descriptions are shown in the official language in which they were submitted.
This invention relates to -the field of electric guitars
of the Spanish type, as distinguished from l-~awaiian or steel
guitars.
It has long been conventional, in electric Spanish
guitars, to stretch the strings over a hridge on the body of
-the guitar and over a nut located a-t the junction between the
fingerboard and the head. Thus, the long operative or
"working" portions o~ the strings are defined between the
bridge and the nut. After passing over the nut, in notches or
narrow grooves therein, the strings connect to tuning screws
located on the head.
At least relative to two of the strings on one major
type of electric Spanish guitar, there are "string guides" on
the head, beneath which such strings pass after bending over
the nut. The string guides are actually holddown elements to
make sure that the strings do not become even momentarily dis-
engaged from the nut when the amplitudes of vibration are
great.
The increasing of the dwell time of a vibrating guitar
string is a major goal of guitar designers, since musicians
want the sound produced by each plucking action to continue
for a substantial time period. Stated conversely, it is de-
sired that the decay rate (decrease in amplitude of vibration) ~~
be low. Prior art attempts to increase dwell (or "sustain")
and reduce decay have been unsuccessful to date, particularly
because in Spanish guitars (as distinguished from conventional
~awaiian ~uitars), the thin, long wooden necks tend to vibrate
(resonate) in response to string vibration and this represents
lost mechanical energy which reduces dwell. For -the same pitch,
in the open-string condition, the string of a Spanish guitar is
conventionally smaller in diameter--and under less tensiQn--than
is the string of a Hawaiian guitar.
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It is possible to increase dwell substantially, even in Spanish
guitars, by using heavy string-anchoring elements, unsightly elements, com-
plex and expensive elements, etc. However, in no case known to applicant
has the dwell been increased markedly by a simple, inexpensive, light, good-
looking element which need have no movable parts. The present invention does
achieve this long-desired result and, furthermore, achieves the advantage of
making it possible to eliminate the above-indicated string guides with
attendant cost saving.
The present invention provides an electric Spanish-style guitar,
which comprises:
(a) a guitar body,
(b) an elongated neck extending from said body and having a head
at the outer end thereof,
(c) a plurality of guitar strings anchored to said body and
extending over a bridge on said body and thence along said neck to adjust-
able tuning means on said head,
said strings being formed of metal and being maintained under
tension by said tuning means,
said strings lying generally in a plane spaced above and
parallel to the fingerboard on said neck,
(d) a nut,
said nut having a body through which said strings extend~
said nut incorporating means to effect two bencls in each
atring as it extends from a region over the outer fingerboard end to a
region over the inner portion of said head, and
(e) means to mount said nut firmly, fixedly and nonslidably at
the junction of said fingerboard and said head,
said bends, said last-named means and said nut body being
adapted to increase the dwells of said strings, in comparison to the dwells
which would occur if the same guitar had a conventional nut.
Each passage inclines at a substantial angle to the operative
string portion and to the axis of the guitar neck. The amount of the angle,
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and the lPngth of the pafisage, are such that there are two distinct and
relatively sharp bends in each string--one bend at each end of the passage.
The bends are in opposite directions, and each preferably has a magnitude
greater than 10 degrees and preferably greater than 15 degrees.
Because each string is confined in its passage through the nut,
there is no possibility that even large-amplitude string vibrations will
cause a string to separate from the nut and shift to an undesired position.
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Figure 1 shows an electric Spanish guitar incorporating
the present invention;
Figure 2 is an isometric view of the head, nut and outer
neck end of the guitar shown in Figure l;
Figure 3 is an enlarged cross-sectional view of the neck,
the section being taken at the nut; and
Figures 4 and 5 are longitudinal sectional views taken
respectively of lines 4-4 and 5-5 of Figure 3 .
Referring first to Figures 1 and 2, a solid-body electric
guitar is shown as comprising a relatively flat solid wooden body
10 from which extends an elongated wooden neck 11 having a head
12 at the outer end thereof. Provided along the upper surface
of neck 11 is the fingerboard 13, there being frets 14 located
at spaced intervals along the fingerboard.
The upper surface of fingerboard 13 lies along the surface
of an imaginary large-diameter cylinder the axis of which is far
below the neck and parallel thereto. The upper surface of head
12 is somewhat below that of the fingerboard, and has tuning
screws or pegs 1~-21 projecting perpendicularly therefrom as is
conventional in six-stringed electric Spanish guitars of the in-
dicated type. Such screws or pegs are rotated (through gears,
not shown) by knobs associated therewith in order to increase or
decrease string tension.
A guitar bridge is indicated at 22 and may be of any suit~
able construction, preferably of the general type shown in Figure
1 of Unitea States Patent No. 2,741,146. However, in the present
bridge there is no vibrato action (such as is shown in the patent),
the upper plate of the bridge (numbered 14 in the referenced
patent~ being instead secured to the guitar body. The bridge, as
described in the referenced patent, is connected to a relatively
heavy metal inertia block which projects into the guitar body.
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Such inertia block is bolted fixedly to the body.
Six strings 23-28 are anchored in the guitar body at a
region on the opposite side of bridge 22 from the neck and head.
This anchoring is effected by enlarged ends such as are described
in United States Patent No. 3,777,613. The strings 23-28 are
metal strings having magnetizable cores which disturb -the fields
of electromagnetic transducers (pickups) such as are shown at 29
and 30 in Figure 1. Thus, the string vibrations are sensed, and
the resulting currents are amplified electrically and then trans-
mitted to loud-speaker means, not shown.
The three lower~pitched strings, numbers 23-25, are
tightly wrapped with a suitable metal such as nickel or nickel
steel. The three higher-pitched strings, numbers 26-28, are not
wrapped ~are bare). As is conventional, the string diameters
vary progressively from the lowest-pitched string 23 (the "sixth
string") to the highest-pitched string 28 (the "first string").
Referring next to Figures 2 and 5, the nut is indicated
at 31 and is a block of a hard, dense material such as metal -
preferably brass and (less preferably) aluminum. The indicated
metals are somewhat less hard than are the metals forming strings
23-28, thus minimizing the possibility of wear on or damage to
the strings caused by the nut.
The lower surface of the block forming nut 31 is flat, as
shown at 32 ln Figure 3, and is in close engagement with a seat
~shelf or ledge) 33 formed on the guitar neck at the outer end
of fingerboard 13. Two screws, numbered 34, project vertically
downwardly through the nut at the ends thereof and are threaded
into the neck to hold the nut tightly against seat 33.
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At its central region, the lower surface 32 OL the n-~t
is recessed somewhat in order to receive the upper portion of
a different kind of nut--namely an elongated bullet-shaped (in
the present emhodiment) internally--threaded nut 35 (Figures
1 and 3) which is provided at the end of a truss rod 35a in
the neck of the guitar. Such truss rods are conventional and
prevent excessive bowing of the neck as well as permitting ad-
justment of the string elevation relative to the upper sur-
face of the fingerboard.
Six small-diameter bores or passages, numbered 36-41,
are provided through the metal block forming nut 31, namely
between the vertical inner face of the block (relatively adja-
cent the body of the guitar) and the vertical outer face there-
of (relatively adjacent the tuning screws). Each such bore is
sufficiently large to receive the associated one of the
strings 23-28, and also to recieve other and somewhat larger-
diameter strings which a particular musician may desire to em-
ploy.
The operative or working portions of strings 23-2~ are
parallel to each other and also parallel to the upper surface
of the fingerboard, being (conventionally) each spaced the same
distance above such upper fingerboard surface. (Thus, as above
indicated, the operative portions lie on the surface of an
imaginary large-diameter cylinder.) Each string is also sub-
stantially parallel to the a~is of neck 11. Bores or passages
36-41, however, are not parallel to the strings (that is to say,
~o the operative or working portions of the strings) nor to the
neck axis, being instead inclined relati~e thereto at a substan-
tial angle.
Preferably, each bore 36-~1 lies in a plane which is
perpendicular to the "plane" of the upper fingerboard surface
and to the "plane" of the strings. The planes containing the
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bores are parallel to each other, and to the axis of the neck.
The bores are spaced laterally from each o-ther by ~he distances
conventionally present between guitar strings at the nut.
Referring -to Figures 4 and 5, the inner ends of the
bores or passages (the bore ends relatively adjacent the bridge)
are disposed at an elevation correspondiny gcnerally to that of
the notches in a conventional nut. The inner bore ends, as
shown in Figure 3, do not lie along a straight line but instead
along a gradual curve corresponding to that of the above-
mentioned imaginary cylinder. The outer bore ends, relativelyadjacent the tuning screws, are disposed much lower than are
the inner ends. Thus, the bores--which are straight--incline
downward]y and outwardly ~rom relatively "high" inner ends to
relatively low outer ends, the latter being relatively close to
the plane of the upper surface of head 12.
With the described construction, there is--for each
string--a first edge at the inner face of the nut block, such
edge being numbered 43. The string bends sharply at this edge,
as shown at 44. At the outer face of the guitar block, there
is a second edge 46 at which a second string bend 47 occurs.
In the preferred construction, the first bend is downwardly and
the second bend is upwardly, the bends thus beiny in opposite
directions.
Each bend is sufficiently shaxp to minimize transmission
of vibrations therethrough. Accordingly, the string portions
49 between second edge 46 and the respective tuning screws 16-
21 are relatively free of vibrations~ These string portions 48
may, for convenience, be referred to as "inoperative" string
portions since it is not desired that they vibrate.
The magnitude of each bend in each string is in excess
of 10 degrees, and is preferably in excess of 15 degrees
However, neither bend should be so sharp as to interfere with
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the tuning functions of elements 16-21, or to create a danger
of damage to or weakening of the strings.
The tuning screws 16-21 may have annu]ar recesses there-
in at predetermined elevations above the upper surface of the
head, and these recesses may be somewhat ahove the second
edges 46 of the bores 36-41. Thus, the ;noperative string
portions ~8, which ex-tend to the tuning screws from the second
edges, may incline somewhat upwardly relative to the surface of
the head. Alternatively, the inoperati~e string portions 48
are substantially parallel to the head.
In the preferred construction, the inclination of each
bore relative to the "planes" of the strings and finger~oard
~s about 20 degrees (for example, 18 degrees). A preferred
spacing between the outer (left in Figures 4 and 5) and inner
(right in Figures 4 and 5) ver-tical faces of the nut block is
1/2 inch. With this inclination, and this spacing, the bends
44 and 47 are sufficiently sharp that the sustain or dwell is
increased markedly and, furthermore, the strings are effective-
ly held in continuous engagement with the first edges 43. No
string guides are shown in the present drawings since none isnecessary, although string guides may be employed if desired
on particular types of gultars.
A spacing, between the outer and inner vertical nut
faces, o~ greater than 1/2 inch does not increase sustain,
whereas a spacing less than 1/2 inch reduces it~--thus making
about 1/2 inch the preferred spacing.
It will thus be seen that the first and second edges 43
and 46 are offset from each other suffici~ntly to provide the
stated bends. Furthermore, the axis of each passage (that is
to say, of each bore 36-41) is inclined relative to the axis of
the neck. The first bend 44 is seen to be at the junction bet-
ween the long, operative string portion and a short string
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region contained within 'che bore, whereas the second bend 47
is between the stated short string portion and the inoperative
string portion 48. It is emphasized that the "inoperative"
string por-tion ~8 of each string is under tension, the string
being stretched between a tuning screw 16-21 and the anchor
point to the yuitar body.
In a specific example, wh;ch-is given by way of illus- -
tration and not limitation, -the nut block 31 is formed of
brass, weighs somewhat over 2 ounces, and has a spacing of 1/2
inch between the vertical inner and outer faces. Bore 36 has
a diameter of 0.067 inch and contains a string 23 having a
diameter of 0.038 inch. The diameter of bore 37 is 0.055 inch
and that of the string 24 contained therein is 0.032 inch. The
diameter of bore 38 is 0.046 inch, whereas that of the contain-
ed string is 0.026 inch. Each of bores 39-41 has a diameter of
0.040 inch, whereas the strings 26-2g respectively contained
therein are 0.015 inch, 0.013 inch, and 0.010 inch.
In comparative tests, using an oscilloscope with a slow
sweep, decay time was measured between an instant when the
output of the transducer (as limited by -the volume control
element of the guitar) was ~0 millivolts to $he instant when
the output of the transducer (as thus limited) was 10 milli-
volts. This 60-10 relationship was employed relative to the
irst five strings (namely, the five higher-pitched strings 24 - -
through 28. Relative to the sixth string 23, the lowest pitch-
cd one, measurements were made between a time when the output
volt~ge from the transducer (as thus limited by the volume
control) was 80 millivolts to a time when it was 20 millivolts,
this latter being done because the dwell was so long that it
exceeded the capability of the oscilloscope at the slowest
sweep. The 60 and 30 millivolt readings occurred a-t the in-
~tant of "attack," namely at the instant the string is released
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by the pick or by the finger of the guitarist.
The results of the tests varied widely, but show that,
typically, the increase in dwell or sustain time between the
above-stated instants is in the range of about 30 percent to
about 50 percent. The increase is sometimes smaller than that
stated, and so~!etimes larger, but the indicated range is typi-
cal. The specified comparative tests were run on the same
guitar, except that in one case it had a conventional produc-
tion model nut and in the other case it had the nut of the
present specific example. Several guitars were thus compara-
tively tested.
In many instances, particularly relative to the lower-
pitched strings, the dwell was increased even when the guitar-
ist had his fingers on the strings between the first and tenth
frets. When the guitarist's fingers were closer to the body
of the guitar, for example above the tenth fret, there was no
sukstantial increase in dwell or sustain~ Thus, the present
invention increases dwell not only in the open-string condition
(no finger on any fret) but in various other string conditions.
There has thus been described a very simple, attractive,
practical, economical, nut, and electric Spanish guitar incor-
porating the same, which make it possible to eliminate string
guides and which in the great majority of instances produce
the major advantage of markedly increased dwell or sustain. - ~
The foregoing detailed description is to be clearly
understood as given by way of illustration and example only,
the spirit and scope of this invention being limited solely by
the appended claims.
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