A stringed musical instrument, such as a guitar, wherein an easily accessible adjustment member allows the user to change the vertical height of the instrument’s neck without affecting the angle of the neck relative to the guitar body. This hinge protects docks from being damaged by stress exerted by the side to side or up and down motion of the wave, storm or high winds. The second of the panels is hollow and receives a portion of the first panel. The created performance model captures nonlinearity characteristics of the semiconductor manufacturing process. The funnel-shaped lower portion of the chamber slopes toward the opening. The self-adjusting side guide includes a first member mounted for movement along the feed deck toward and away from the documents; a guide wall mechanism operatively connected to the first member for movement relative to the first member; and a biasing device that applies a biasing force that biases the guide wall into a first position relative to the first member.