Abstract:
A sliding saddle system and a method of constructing a chordophone instrument comprising an underblock in slidable engagement with the bridge plate. A connector is located between the saddle and the underblock allowing the underblock to slide into position on the bridge plate until the connector is tightened, thereby locating the saddle on the sound board.

Description:
FIELD 
       [0001]    The present technology is directed to a string instrument in which the stresses and strains on the soundboard are reduced through the implementation of a sliding saddle system, an interior strut and an offset headstock. More specifically, the present technology is directed to a guitar having sliding saddles, an interior strut and an offset headstock. 
       BACKGROUND 
       [0002]    Acoustic string instruments are subjected to high stresses and strains caused by the strings. As the instrument is tuned, the strings are tightened, leading to force developing between the neck and the soundbox. The direct recipient of the force is the bridge. The force is then indirectly exerted on the soundboard. This may lead to damage to both the bridge and the soundboard. In extreme cases, the neck can also be affected by damaging the joint between the neck and the soundbox of the instrument. 
         [0003]    The inner surfaces of the soundboard and back of guitars are provided with bracing to counteract the force. A complex pattern of bracing is used on the inner surface of the back. During construction of the instrument, a luthier spends a significant amount of time shaping the bracing in order to tune the instrument. In order to reduce the work, Griffiths (U.S. Pat. No. 6,333,454) provides a bracing system that combines kerfing, binding and bracing. One unit is for use with the soundboard and a second unit is for use with the back. 
         [0004]    In U.S. Pat. No. 7,462,767, a bracing system is used to counter balance the force by using an additional string or cable, preferably made of Kevlar, carbon fiber or a similar non-elastic material that is attached to the bridge and the neck of the guitar within the soundbox. A bracket is located inside the soundbox of the instrument and attached to the bottom of the bridge of the instrument. It is connected to an adjustable brace by a non-elastic string. The adjustable brace may adjust the tension placed upon the string to control the amount of counter-balancing tension. This system does not alleviate the force, but rather, simply counter balances the force. 
         [0005]    Another cause of stress to the instrument arises because the strings are not aligned between the headstock and the bridge such that they are normal to the bridge. The strings therefore exert a twisting force on the bridge and soundbox. 
         [0006]    Despite the fact that many instruments are damaged by the two forces, those of the force on the bridge and soundboard and the force on the neck and the soundbox, the string instrument industry is reluctant to make change to reduce the forces exerted, preferring to retain the “look” of the instrument in preference to the health of the instrument. 
       SUMMARY 
       [0007]    The present technology provides combinations for reducing the forces exerted by the strings on instruments in the chordophone family. 
         [0008]    On aspect is a sliding saddle system reduces the tension on the soundboard thereby allowing the top to resonate freely with minimal bracing for strength, as much of the tension is relieved. The sliding saddle system also allows for intonating each string easily. 
         [0009]    Another aspect is a strut that runs from the neck distal end to the distal end of the soundbox, more specifically, to the end block located at the distal end of the soundbox. The strut has course and fine adjustors to allow adjustment towards and away from the soundboard. Adjustment of the strut position adjusts the neck angle and the string height. 
         [0010]    Yet another aspect of the combination is an offset headstock. The offset headstock has two tuning keys and the side opposite to the offset has four tuning keys. It reduces the stresses and strains on the nuts of the guitar. 
         [0011]    The technology further provides a kerfing unit that is integral with the soundboard and the back. This allows for easy and quick assembly of the string instrument and, as it the 70% smaller than conventional binding and kerfing, it provides more resonant area. It also reduces the number of steps in construction. 
         [0012]    Another aspect of the technology is a peripheral tuning groove. 
         [0013]    A method of constructing a chordophone instrument with the above features is also provided. 
     
    
     
       FIGURES 
         [0014]      FIG. 1  is a perspective view of the guitar of the present technology. 
           [0015]      FIG. 2  is a longitudinal section view of the guitar of  FIG. 1 . 
           [0016]      FIG. 3  is an end view of the guitar of the  FIG. 1 . 
           [0017]      FIG. 4  is a cross sectional view of the kerfing unit of the present technology prior to removal of the outer contour. 
           [0018]      FIG. 5  is a plan view of the sliding saddle system of the present technology. 
           [0019]      FIG. 6  is an exploded view of the neck region of the technology of  FIG. 1 . 
           [0020]      FIG. 6A  is a plan view of the soundboard of the technology of  FIG. 1 . 
           [0021]      FIG. 7  is a longitudinal section view of the technology of  FIG. 1 . 
       
    
    
     DETAILED DESCRIPTION 
       [0022]    A guitar, generally referred to as  10  is shown in  FIG. 1 . The guitar has a headstock  12  and a neck  14  extending therefrom. The neck  14  is connected to a soundbox, generally referred to as  16  at a proximal end  18  of the soundbox  16 . The soundbox  16  has a soundboard  20  forming the top of the soundbox  16  and sides  22 . The soundboard  20  has a narrow, 2 mm deep groove around the periphery referred to as a “peripheral tone groove” 21 . The tone groove  21  allows the soundboard  20  to be more flexible. A sound hole  24  is located centrally in the soundboard  20 . Slots  26 , corresponding in number to the number of strings  28  are also located in the soundboard  20 . The headstock  12  is provided with tuning keys  30 . In the prior art, the headstock is symmetrical and there are an equal number of tuning keys  30  on either side of the headstock  12 . In contrast the headstock  12  of the present technology has an offset  32 . There are two tuning keys  30  located on the same side as the offset  32  and four tuning keys  30  located on the side opposite to the offset  32 . This allows the strings  28  to extend in a parallel manner between the headstock  12  and a sliding saddle system, generally referred to as  34  and to be normal to the sliding saddle system  34 . A stationary voice coil with moving magnet  35  is provided to move the soundbox  16 . 
         [0023]    As shown in  FIG. 2 , it can be seen that the soundbox  16  is defined by the inner surface  40  of the soundboard  20 , the inner surface  42  of the sides  22  (see  FIG. 4 ) and the inner surface  44  of the back  46 . The neck is attached to the neckblock  48  and has an integral fretboard with frets  29 . The strings  28  pass over the frets  29  and nuts  31  do not terminate at pins that are engaged with the bridge as occurs in the guitar prior art or the tail piece as occurs in the violin prior art, but rather terminate at the sliding saddle system, generally referred to as  34 . 
         [0024]      FIG. 2  also shows a strut  50  that abuts an end block  52  located on the distal inner surface  54 , and is adjustably affixed by a bolt  56  or by the strap peg. As shown in  FIG. 3 , the bolt  56  extends through a substantially vertical slot  58  (vertical in this context means that it extends a distance between the soundboard  20  and the back  46 ) in both the end block  52  and the side  22  at a distal end  100 . The arrow shows how the placement of the bolt  56  can be adjusted. A fine adjustment screw  60  in the end block  52  is vertically disposed and abuts the bolt  56 . The adjustments alter the effective length of the strut  50 , in other words, the distance between the distal end, generally referred to as  100  and the proximal end, generally referred to  18 , of the soundbox  16  (as shown in  FIG. 2 ). More significantly, the adjustment allows for adjustment of the height of the strings, by adjusting the neck angle. This is of further benefit because it doesn&#39;t change the break angle of the strings. A plate  62  is located on the strut  50  on an upper surface  64  and abuts the neck  14  at the neck distal end  66 . 
         [0025]    As shown in  FIG. 4 , during construction, a kerfing unit, generally referred to as  104  is integral with the back  46  and the soundboard  20 . The kerfing unit  104  is comprised of an inner contour  106  and an outer contour  108  with a valley  110  therebetween. The unit  104  runs the perimeter of the back  46  and the soundboard  20 . The sides  22  are seated in the valley  110  and glued in place. The outer contour  108  is then removed by routing, or laser cutter, or the like, leaving an integral kerfing unit  104  to provide structural support for the soundbox  16 . The kerfing unit  104  is significantly smaller than conventional kerfing and is both easier to construct and use during construction of the guitar  10 . Further, binding is not required. 
         [0026]    The sliding saddle system  34  (shown in  FIG. 1 ) consists of a series of saddles  120 , a series of connectors  122 , a series of underblocks  124  and a bridge plate  126 . The number of saddles  120 , connectors  122  and underblocks  124  correspond to the number of strings  28  and the number of slots  26 . As shown in  FIG. 5 , each saddle  120  is in engagement with an underblock  124  by means of a connector  122 . The bridge plate  126  is located in the soundbox  16  and is tapered distally, such that it is thickest towards the neck  14  of the guitar  10 , i.e. it tapers distally normal to the longitudinal axis of the saddle. It is glued to the inner surface  40  of the soundboard  20  and is slotted. The underblock  124  abuts the bridge plate  126 . The connector  122  is adjustable and when loosened allows the saddle  120 , connector  122  and underblock  124  to move proximally and distally in the slot  26 . The combination of the saddle  120 , connector  122  and underblock  124  therefore both allows for adjusting intonation of each string  28  and relieves tensions that would normally be present on the bridge and soundboard of a conventional guitar. This allows the soundboard  20  to function solely as a resonant membrane rather than a structural support and resonant membrane. 
         [0027]    Each saddle  120  has a wedge-shaped opening at a proximal end to engage the string  28 . The string  28  passes through the wedge-shape opening and passes through the slot  26  in both the soundboard  20  and the bridge plate  126 . The string  28  terminates in a recess  128  on an underside  129  of the underblock  124 , as shown in  FIG. 5 . 
         [0028]    In another embodiment, the connector  122  is integral with the saddle  120  and the unit is constructed of a material, such as a plastic polymer. 
         [0029]    In all embodiments, in order to reduce stresses on the soundboard  20 , it is preferable that the circular movement of the strings  28  when strummed is accommodated by resultant movement of the saddles  120  in at least two planes (up and down and side to side) and preferably in a circle, therefore in all embodiments the connector  122 , whether integral or not is selected to provide such movement (referred to as “substantially rotatable”). Additionally, the design reduces torsional stress on the soundboard. This differs from a conventional guitar as the pins of a conventional guitar only accommodate up and down movement of the strings  28 , thereby resulting in torsional stress on the soundboard. 
         [0030]    As shown in  FIG. 6 , it can be seen that a soundbox aperture  200  is provided in the soundbox  16  for receiving the neck  14  and strut  50 . These are assembled and then introduced as a unit. The neck  14  and integral fretboard with frets  29  is accepted into the soundhole slot  202 , which is an extension of the soundhole  24 . This can be seen in inset  6 A. A bolt  204  retains the neck  14  to the neck block  48 . 
         [0031]    As shown in  FIG. 7 , the saddles  120  are can be each provided with transducers  206  or musical instrument digital interface (MIDI). This allows for individual processing of each string. 
         [0032]    The guitar of the present technology can be assembled very quickly as follows: 
       1. Construction of the Body of the Guitar: 
       [0033]    The soundboard and the back are machined to have the integral kerfing unit  104 . This is used to attach the sides  22  to the soundboard  20  and back  46  of the guitar  10 . Once glued, the outer contour  108  is removed by routing or laser cutting or the like. 
       2. Introduction of the Strut: 
       [0034]    The neck  14 , neckblock  48  and strut  50  are slid into the soundbox  16  of the guitar  10  as a unit, through the soundbox aperture  200 . The strut  50  abuts the end block  52  located on the distal inner surface  42 , and is adjustably affixed by a bolt  56  or by the strap peg. The bolt  56  extends through a substantially vertical slot  58  (vertical in this context means that it extends a distance between the soundboard  20  and the back  30 ) in both the end block  52  and the side  22  at a distal end  100  of the guitar  10 . The strut is adjusted by adjusting both the bolt  56  and the adjustment screw  62 . 
         3 . Introduction of the Sliding Saddle System: 
       [0035]    The sliding saddle system  34  is then assembled by placing the series of saddles  120  on the soundboard  20 , slotting the connectors  122  into the slots  26 , attaching them to the underblocks  124 , and tightening the connectors  122  such that the saddles  120  are located on the soundboard  20  and the underblocks  124  are located on the bridge plate  126 . 
       4. Adjustment of the Strut: 
       [0036]    Adjustments are made by altering the position of the bolt  56  by sliding it up or down in the vertical slot  58 . Screw  62  is used to make fin adjustments. Once appropriately located, the bolt  56  is tightened. These adjustments alter the angle of the neck. 
       5. Stringing the Instrument: 
       [0037]    The instrument is strung by threading each string  28  through the wedge-shaped opening on the saddle  120 , through the soundboard  20  via the slots  26  and terminating the string  28  on the underside of the corresponding underblock  124 , by wedging the string  26  into the recess  128  in the underside  129  of the underblock. The strings  28  are wound onto the tuning keys  30 , noting that the alignment of the strings  28  is kept normal to the sliding saddle system  34  by the offset  32 . In the preferred embodiment, this comprises attaching two strings to the tuning keys in the vicinity of the offset and four strings to the tuning keys opposite the offset. 
       6. Intonating the Guitar: 
       [0038]    The sliding saddle system  34  is slid proximally or distally in the slots  26  and along the bridge plate  126 . Once located, the connectors  122  are tightened such that the sliding saddle system  34  is firmly located in place on the soundboard  20  and the bridge plate  126 . 
       7. Tuning the Strings: 
       [0039]    The sliding saddle system  34  and strut  50  allow the soundbox  16  to be vibration free or essentially vibration free, because string contact and tension can be eliminated from the sound box. A digital system such as, but not limited to Antares Auto-Tune® can be used to adjust and correct the pitch of each string. Such adjustment has not been useful for acoustic guitars, because of the soundbox vibration. 
         [0040]    If the guitar  10  is adjusted to provide an essentially vibration free soundbox  16 , the stationary voice coil with moving magnet  35  can be used to control movement of the soundboard  20 . 
         [0041]    The foregoing is a description of an embodiment of the technology. As would be known to one skilled in the art, variations that do not alter the scope of the technology are contemplated. For example, the instrument may have more or less than six strings and need not be a guitar, but any instrument in the chordophone family, for example but not limited to a violin, a ukulele, lute or mandolin. Regardless of the plurality of strings, the offset will allow for an uneven distribution of the tuning keys between the sides of the headstock, thereby allowing for the strings to be normal to the sliding saddle system. Further, more than one set of strings can be used, for example, the instrument could have a six string and twelve strings embodiment, and more than one strut could be employed. The neck and strut could be a unit body construction, the strut could be a solid member, or could be a truss. The sliding saddle system could be a variety of shapes. The guitar may be provided with only the strut and related components, or may be provided with both the strut and sliding saddle system. The peripheral tone groove is generally ½the thickness of the soundboard, but may be ¼ the thickness, or ⅜ the thickness, or as much as ⅝ the thickness and is located in the vicinity of the periphery of the soundboard, for example, but not limited to, between 1 and 3 cm from the periphery, more preferably 1.5 to 2.5 cm from the periphery and most preferably 2 cm from the periphery.