{
  "title": "Guitar fret positions: equal temperament and divide by 18",
  "description": "Fret positions for an ideal string, one row per fret (1 to 24) and string length (648 and 628 mm). Equal-tempered fret n sits at L(1 - 2^(-n/12)) from the nut, a semitone being a frequency ratio of 2^(1/12), about 1.05946; divide-by-18 fret n sits at L(1 - (17/18)^n). Cents between two vibrating lengths are 1200 log2(longer/shorter), one cent being a hundredth of an equal-tempered semitone; a frequency ratio r spans 1200 log2(r) cents, so a ratio of 3 spans about 1901.96 cents, 19.02 semitones. Cents per mm are 1200/(ln 2 x the remaining length). Computed for this page; tension, thickness and material held fixed.",
  "license": "CC BY 4.0",
  "license_url": "https://creativecommons.org/licenses/by/4.0/",
  "creator": "Tricks of Ear and Eye",
  "page": "https://tricksofearandeye.com/instruments/guitar-fret-spacing/",
  "derived_from": [
    "Computed by Tricks of Ear and Eye from L(1 - 2^(-n/12)) and L(1 - (17/18)^n) for L = 648 mm and 628 mm; ideal string, frequency inversely proportional to length (Tyndall, Sound)"
  ],
  "method": "Compiled by Tricks of Ear and Eye from the data listed"
}