Scale of harmonics

The scale of harmonics is a musical scale based on the noded positions of the natural harmonics existing on a string.^{[citation needed]} This musical scale is present on the guqin, regarded as one of the first string instruments with a musical scale.^[1] Most fret positions appearing on Non-Western string instruments (lutes) are equal to positions of this scale. Unexpectedly, these fret positions are actually the corresponding undertones of the overtones from the harmonic series.^{[example needed]} The distance from the nut to the fret is an integer number lower than the distance from the fret to the bridge (see: superparticular number).