Abstract: Electric stringed musical instruments having an elongated fingerboard, an upper headpiece and nut and a lower tailpiece and bridge, with a first set of primary frets placed in regular sequence along the fingerboard from its upper end to is lower end and a set of secondary frets each placed intermediate a pair of primary frets along the fingerboard. Each secondary fret is so placed between two primary frets that upon depression of a string of the instrument between any selected pair of frets comprising a primary fret and an adjacent secondary fret, accompanied by plucking or strumming of the string, two harmonically resolved musical notes are generated. One of such notes is related to the length of the portion of the string between the lower fret of the selected pair of frets and the lower bridge of the instrument and is picked up by a pickup head of a lower magnetic pickup assembly.