Patent ID: 7414184

Claim:
An auxiliary device for applying alternative predetermined tension states upon the string(s) of various types of stringed musical instruments comprising: main body, said main body to engage upon said string(s) at two longitudinally opposing outer points, said main body to have clearance for said string(s) to be deflected between said outer points; control handle, said control handle to incorporate diametrically opposing surfaces about an axis of rotation, said diametrically opposing surfaces to receive concurrent manual force during operation, said control handle to have a rotational freedom of movement limited to no more than one full turn by means of at least two clearly discernable stop points; actuator, said actuator to deflect said string(s) at a point in between said outer points of said main body, said actuator to deflect said string(s) in accordance with the rotation of said control handle; calibration control, said calibration control to critically pre-determine the extent to which said actuator deflects said string(s) between said outer points of said body in accordance with the rotation of said control handle; wherein, rotation of said control handle from one said stop point to another said stop point causes said actuator to deflect said string(s) against said outer points of said main body to an extent pre-defined by said calibration control whereupon the device will apply a different tension state upon the string(s) at either stop point and whereupon the difference between said tension states will produce an interval in pitch of at least one semi-tone upon the vibrating string(s), and wherein, the manual force applied to said control handle to drive the device between the tension states applied to said string(s) will be in the form of a couple, the pure rotational force of which has no tendency to displace the device along said string(s) nor to cause angular deviation to those lengths of said string(s) which are adjacent to the device during operation, and wherein, the device is accordingly capable of stable single-handed operation without relying upon physical contact with any other part of the host instrument except said string(s).