an apparatus for doubling of the length of each string of a stringed instrument using two legs of an extended string . the effective longer string length allows for the production of a lower tone range without lengthening the neck of the instrument , or the same tone range while shortening the neck of the instrument . if required to prevent bowing of the neck , a reinforcing structure may be included to the neck structure or in a second preferred embodiment a buttress support to the neck of the instrument may be provided . the height of the paired strings above the fret board may also be adjusted .