Neutral third
| Inverse | neutral sixth |
|---|---|
| Name | |
| Other names | - |
| Abbreviation | n3 |
| Size | |
| Semitones | ~3½ |
| Interval class | ~3½ |
| Just interval | 11:9, 27:22, or 16:13 |
| Cents | |
| Equal temperament | 350 |
| 24 equal temperament | 350 |
| Just intonation | 347, 355, or 359 |
A neutral third is a musical interval wider than a minor third 
play but narrower than a major third play , named by Jan Pieter Land in 1880; the name has been taken over by Alois Hába. Three distinct intervals may be termed neutral thirds:
These intervals are all within about 12 cents and are difficult for most people to distinguish by ear. Neutral thirds are roughly a quarter tone sharp from 12 equal temperament minor thirds and a quarter tone flat from 12-ET major thirds. In just intonation, as well as in tunings such as 31-ET, 41-ET, or 72-ET, which more closely approximate just intonation, the intervals are closer together.
A neutral third can be formed by stacking a neutral second together with a whole tone. Zalzal's wosta, a neutral third of 354.55 cents, may be constructed through the addition of a whole tone and a three quarter tone: 9/8 X 12/11 = 27/22. Based on its positioning in the harmonic series, the undecimal neutral third implies a root one whole tone below the lower of the two notes.
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