Device for changing the tonality of string instruments

Abstract

The device is installed in the neck of a stringed instrument (8). The device, through its movable and immovable elements, raises a movable fret (4) that establishes direct contact of the fret with the strings (23) of the stringed instrument. The movable fret (4) lies in the channel (5) on the neck of the string instrument (8), so that its upper surface with the fingerboard (22) forms one continuous and smooth surface. The tonality of the instrument is changed by means of the switch (20) on the neck of the string instrument (8). The device recognizes two states, active - when the tonality has been changed and inactive - when the string instrument is in its original tonality. By means of the movable fret (4), the length of the string (23) is shortened, thereby changing the fundamental harmonic with which the string (23) oscillates. By carefully choosing the location of the channel (5) in which the movable fret (4) is located, a change in tonality by half a step or more can be achieved. The change of tonality is reversible, so the transition from active to inactive state is achieved with the same device as the transition from inactive to active.