Neutral third

From Wikipedia, the free encyclopedia

A neutral third is a musical interval between a minor third and a major third. Two distinct intervals may be termed neutral thirds. The larger one is an equal-tempered neutral third, which is characterized by a difference in 350.00 cents between the two tones, a hair larger than a ratio of frequencies between the two tones of 11:9. The smaller neutral third, called the undecimal neutral third, has a ratio between the higher-frequency tone to the lower-frequency tone of exactly 11:9.

Roughly speaking, then, neutral thirds are a quarter tone sharp from minor thirds and a quarter tone flat from major thirds. The equal-tempered neutral third may be found in the quarter tone scale and in some traditional Arab music (see also Arab tone system)). Undecimal neutral thirds appear in traditional Georgian Music.