Abstract:
A movable pickup mounting system is disclosed, which consists of a “wiper” arm and thereupon mounted electromagnetic pickup unit, movably attached to the body of the stringed instrument, to provide a means of moving the pickup through different positions along the string path and thus achieve different tonal effects.

Description:
[0001]     This application claims benefit of the Provisional Patent Application received by USPTO Mail center on Dec. 9 th , 2002 Serial No. unknown 
     
    
     BACKGROUND OF THE INVENTION  
       [0002]     1. Field of Invention  
         [0003]     This invention relates to stringed musical instruments in general and electric guitars and basses having a movable pickup system in particular.  
         [0004]     2. Prior Art  
         [0005]     Several designs for movable pickups have been disclosed in the past. Some designs are for slideable pickups, some for rotateable. The general purpose is to position the pickup along different sections of the vibrating string and thus effect a change in the sound quality of the instrument. The closer a pickup is to the bridge of a stringed instrument, the more it will pick up treble frequencies. As it is moved closer to the neck part of the instrument it will increasingly favor bass response. Furthermore, there are along the vibrating string so-called “harmonic nodes”, locations where the harmonic content of the plucked note is emphasized. These are called “sweet spots”. Depending on scale length, tuning and the actual note played these sweet spots vary. A movable pickup can be placed in the optimal location to capture the desired tonal characteristic. A two- or three-pickup instrument attempts to capture these varying characteristics but is limited a) by the fixed location of the pickups, and b) to achieve “in between” sounds, output from two pickups has to be electronically mixed, resulting in phase shifts (since the two pickups simultaneously record a slightly different waveform of the vibrating string). These disadvantages have led to development of movable pickup mounting designs.  
         [0006]     Slideable pickup mounting designs have the advantage of more effectively shaping the tonal characteristics of the instrument by allowing placement of the pickup at relatively more distant locations along the string path. Rotateable designs place the pickups at different angles relative to the string path, which results in subtle shifts in tone, or as is the case in Pagelli 716, interesting tonal effects which however do not find widespread use or acceptance. Each of the designs in the prior art either exhibit deficiencies which this new design overcomes, or are meant to produce a different effect from the one produced by this design. Most slideable designs are cumbersome in use and prone to mechanical failure in the field while rotateable designs are severely limited in the range of tonal manipulation they offer.  
         [0007]     Some References:  
                                       3,780,202   Clement R. Law       3,911,777   Rendell       4,261,240   Aaroe       5,012,716   Claudio Pagelli                  
 
         [0008]     Field of Search: 84/723 
        84/1725-729     84/743        
 
       SUMMARY OF THE INVENTION  
       [0011]     The object of the present invention is to provide the most useful and broad changes in the tonal spectrum of a musical stringed instrument, while maintaining a simple and effective mechanism, which can be manufactured at low cost and will remain trouble free and is easy to operate. In this preferred structural embodiment the instrument is an electric bass.  
         [0012]     The present invention includes an electromagnetic pickup, which is mounted on a pivoting arm, constituting an assembly, which in turn is movably affixed to the guitar body at one end. The pickup can thus be moved, in a “wiping” fashion, describing an arc, substantially coplanar with the path of the strings, along the length of the strings, thus picking up different tonal characteristics depending on its position. The “wiper arm” is fitted with means of mounting the pickup, and the connecting wire runs from the pickup through a channel in the wiper arm to a respective channel routed into the body near the pivot point of the wiper arm, so that it remains flexibly connected at all times to the electronics cavity in the guitar or bass body. In this preferred embodiment an adjustable screw with friction washers is used as pivot point and anchor for the wiper arm. The frictional force exerted by the screw determines the ease with which the wiper arm may be moved and will cause the arm to stop and remain in the position selected.  
     
    
     BRIEF DESCRIPTION OF THE DRAWINGS  
       [0000]     Page 1  
         [0013]      FIG. 1  is a front view of the pickup/wiper arm assembly situated on the body of a bass guitar.  
         [0014]     The pickup  1  is mounted to the wiper arm  2 , which is movably attached to the body of the instrument  3  by the pivot screw  4 . The strings  5  are connected on one end to the bridge  6 , at the other end to the headstock  7  of the instrument. The instrument may be provided with tone and volume controls  8  and with an output jack  9  for connection to an amplifier.  
         [0015]      FIG. 2  is a side view of the pickup/wiper arm assembly  
         [0016]     The pickup  1  is affixed to the wiper arm  2  by means of screws or other fastening devices  10 . The connecting wire  11  issues from an opening at the base of the wiper arm  2   
         [0000]     Page 2  
         [0017]      FIG. 3  is a top view of the wiper arm assembly with the wire connecting the pickup to the body cavity  
         [0018]     The pickup connector wire  11  runs through a channel  12  in the wiper arm  2  to a respective channel  13  routed into the body of the instrument  3 , allowing for sufficient flex in the wire  11 .  
         [0019]      FIG. 4  is a side cut-away view of the pivot screw attachment and wiper arm assembly  
         [0020]     The wiper arm  2  is moveably mounted to the body of the instrument  3  by means of the pivot screw  4 . The friction washers  14  and  15  allow variable pressure to be exerted and the achievement of variations in the ease of movement of the wiper arm  2 . The countersunk insert  16  in the body provides a permanent and durable means of attachment for the pivot screw  4   
         [0021]      FIG. 5  is a side cut-away illustrating the slanting sliding plane as the pickup moves towards or away from the bridge  
         [0022]     The plane of the sliding surface  17  of the musical instrument body  3  for the wiper arm  2  is lightly sloped. Position  17 A is closer to the strings than position  17 B, thus compensating for the increase in volume as the pickup travels from position  17 A towards position  17 B. 
     
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT  
       [0023]     A top view of an electric stringed musical instrument, in this preferred embodiment a 4-string bass guitar, is shown in  FIG. 1 , having a neck and headstock with tuning mechanisms  7 , strings  5  which are anchored to the body  3  by the bridge  6 . The pickup  1  is shown mounted on the “wiper” arm  2 , in this preferred embodiment attached to the body of the instrument  3  by a screw  4 . The pickup may be moved back and forth in the pie-shaped recess  18  routed into the body  3 . The recess  18  defines the range of movement available to the wiper arm  2 . It also allows the assembly of wiper  2  and pickup  1  to be nearly flush with the top of instrument body  3 , thus preventing it from interfering with the musician&#39;s playing. While playing, the musician may use his thumb placed on the top end of the pickup  1  farthest from the pivot point  4  to easily alter the position of the pickup  1 . Adjustment of the screw  4  will result in more or less friction being applied to the wiper arm  2 , thus enabling the musician to select the proper tension for his playing style. He may also find a “sweet spot” and tighten the pivot screw  4  to maintain the pickup  1  and wiper arm  2  permanently in the desired position. Additionally the pickup  1  will provide the musician with a “thumbrest” in the appropriate playing position for the respective tonality desired. Specifically, a bass player&#39;s hand will move closer to the bridge  6  when brighter sounds are desired, corresponding to the position of the pickup  1  and wiper arm  2 , or conversely, closer to the neck  7  for warmer tones. The range of movement of the pickup  1  covers most of the commonly desirable positions and additionally allows for an almost infinite number of alternate positions. It has been found that the present invention greatly enhances the versatility and usefulness of a standard stringed musical instrument by enabling the musician to tailor the sound quickly and effectively to his playing style.  
         [0024]      FIG. 2  shows a view of the wiper arm  2  with attached pickup  1  assembly. By means of the screws  10  which affix the pickup to the wiper arm  2  and internally located springs  19  which exert upward pressure to counteract the downward pressure of the screws  10 , the pickup  1  can be raised or lowered respective to the wiper arm  2  so as to allow for proper adjustment of the ideal string-to-pickup distance. As can be seen in  FIG. 3 , the cable  11  runs from the pickup  1  in a groove  12  at the bottom of the wiper arm  2 , exits near the pivot point  4  and enters the body of the instrument  3  by means of the opening  13 .  
         [0025]      FIG. 4  shows a cutaway of the wiper arm  2  with the tensioning screw  4  in the preferred embodiment. Alternately a thumb screw or other screw design may be substituted, the main objective being to provide friction which causes the wiper arm to remain in the selected position and to adjust such friction quickly and effectively during use of the instrument. Washers  14  and  15  allow the wiper arm  2  to move while retaining the screw  4  in its position in the bushing or anchor  16  which is affixed into the instrument body  3 .  
         [0026]     The simplicity of the design allows for easy manufacture and maintenance and provides an effective means of shaping the tone of the instrument “on the fly”.  
         [0027]     Furthermore, the arc of the wiper arm&#39;s  2  path may be designed so as to angle the pickup  1  more or less respective to the string path, thus producing more or less extreme tonal effects. Also the wiper arm  2  may be longer or shorter and thus effect subtle changes in the geometry of the sensing arc, any of which may be deemed more desirable in some particular instance. In addition the plane of the wiper&#39;s arm  2  arc is lightly sloped respective to the string path, so as to position the pickup progressively closer to the strings as it moves towards the bridge, thus counteracting the diminution in volume effected by the reduced vibrational energy exerted by the strings in proximity of the bridge.  FIG. 5  illustrates a cutaway view of the instrument body  3  with the recess  18  routed in such a way as to create a slope, placing the pickup  1  closer to the strings  5  at the endpoint of the arc  17 A near the bridge  6 , thus counteracting the diminuition of string energy encountered near the “witness” point at the bridge  6 . As the wiper  4  with pickup  1  is moved closer to the neck of the instrument, increased vibrational energy from the strings  5  will cause the volume output to rise. This is counteracted by placing the wiper and pickup further from the strings  5  at the end point of the arc  17 B.  
         [0028]     In summary, the present device opens a wide range of possibilities which is not possible with conventional pickup attachments or with the pickup-head devices disclosed in the background of the invention. The foregoing description and drawings merely explain and illustrate the invention, and the invention is not limited thereto except insofar as those who have the disclosure before them are able to make modifications and variations therein without departing from the scope of the invention.