1. Field of the Invention
The invention relates generally to a stringed musical instrument which is designed to address medical problems particular to electric bass players or to players of a six string guitar. The design of the instrument increases the efficiency of the muscular tendon system of the hands, wrists and arms, thereby reducing for the player, the risk of developing the many overuse or repetitive strain injuries to which guitar and bass players are prone. In short, the invention makes the playing positions, both chording and plucking, more comfortable.
Playing a musical instrument requires a high degree of dexterity and finely controlled, repetitive, often rapid movements by particular parts of the body, primarily the upper extremities. Frequently, such movements are required over extended periods of time. Even small errors in the bio-mechanical systems of the upper extremities can have disastrous effects on one's ability to perform on his or her instrument, some to the point of threatening or ending careers. Playing related disorders are extremely prevalent in the United States. Most musicians who suffer from playing related problems suffer from some form of overuse syndrome which is defined as the damage that occurs when the tissue is stressed beyond its anatomical or physiological limits, whether acutely or chronically. Overuse syndrome is frequently used synonymously with the term repetitive strain injury. Examples of playing related disorders suffered by musicians are: tendonitis and tenosynovitis, myofascial pain, tension myalgia, fibromyalgia, fibrositis or a nerve entrapment syndrome such as carpal tunnel syndrome. In addition, musicians suffer from disorders which may stem from the central nervous system often referred to as an occupational craft palsy such as occupational neurosis or involuntary cramping of the hand.
Guitar and bass players comprise a group that are at a relatively high risk of developing playing related injuries. In most instances, the injuries are due to the hand, wrist and arm positions required to play the instrument. The standard bass guitar has a scale length of 34 inches. This is a distance that the string travels from the contact or "witness point" at the bridge to the contact at the nut, and is compared to a scale length of 24 to 26 inches on a standard six-string guitar. Due to the growing popularity of five and six-string basses as opposed to the standard four-string, which have an extra string in the low register, many basses are being made with a 35 or sometimes even 36 inch scale length. The reason for this is to create added tension on the heavier gauge string so that notes may ring truer. What this means, however, is that the neck of the bass is very long compared to the guitar, requiring a long reach of the bassist.
In the course of describing the relative positions of the upper limbs when playing the bass guitar, a "right-handed" style will be assumed. The left hand refers to the hand which depresses the string to the fingerboard, and the right hand refers to the hand which plucks or strums or in some way sets the strings into vibration. The bass is played in a similar way to the guitar, either sitting or standing and, if standing, supported by a shoulder strap. With the instrument held more or less horizontally, the left hand comes from underneath and behind the neck of the instrument and the fingers curl around the neck to depress the strings against the fingerboard. The thumb is placed either flat on the back of the neck or curled around the top of the neck, usually the former. The most efficient and most advocated technique for the left hand is to use the tips of the fingers to depress the strings.
The right hand comes over the top of the instrument and assumes the position for plucking or strumming the strings. This position constitutes the major difference between playing guitar and bass. The guitar is usually played with a pick or with the fingers, either strumming across the strings or plucking individual strings. While the bass can also be played either with a pick or percussively with the side of the thumb, it is generally played using the fingertips.
The first principal for correct technique at any instrument or indeed in any repetitive activity is economy of motion. Only those motions directly related to the task should be employed. For bass players in order for the right hand and fingers to be in a position for good technique, and the right arm to be relaxed in order to prevent unnecessary muscular activity, the wrist is prone to extreme degrees of flexion. Wrist flexion, coupled with the repetitive and fairly substantial muscular demands of the fingers, places the bass player at a high risk of developing overuse syndrome, particularly tendonitis, tenosynovitis and carpal tunnel syndrome. The more a guitarist is able to reduce this hyper-flexed position toward a neutral wrist position, the less vulnerable the musician appears to be to suffer hand, wrist and arm problems.
The present invention addresses a solution to the problem of overuse injury by bass players.
2. Invention Disclosure Statement
Currently, only one design of a musical string instrument addresses in a very limited way the comfort of the player. One known design which is the subject of a patent granted to Leo L. Burrell (U.S. Pat. No. 4, 534,260) aligns the assembly of the bridge and nut of the musical instrument in such a way that chording finger positions are comfortable. This is achieved by Burrell by rotating the nut relative to the bridge.
The present invention is a significant advance or improvement over Burrell in that ergonomic function is accomplished by rotating both the nut and the bridge about a central longitudinal axis, each rotated in the direction from which the player's hand approaches, and each one set at angles relative to the plane of the instrument body. This is done because the body contacts the player and therefore defines the angles in relationship to the rest of the instrument relative to the player. The chording hand approaches the neck and strings from underneath, therefore, the nut is rotated downward, reducing the amount of wrist flexion required for normal technique. Similarly, the plucking hand approaches the strings from above so the bridge is rotated upward, also reducing unwanted wrist flexion. The result of these rotations is an instrument neck containing a compound twist. Also, the present invention comprises a fingerboard which contains a compound radius, with a smaller radius at the nut and a larger radius at the body end. The fingerboard is also tapered in the present invention to cause greater string spacing at the bridge than at the nut.