German sixth chord: Difference between revisions

Per discussion, list the 5-limit chord separately.
m In meantone: 75/64~125/108 could be useful too
Line 6: Line 6:
If we stick to the [[5-limit]], which traditional tonal harmony mainly concerns, the augmented sixth represents both [[125/72]] and [[225/128]]. It is treated as a rare and special dissonance, especially when used on the sixth degree. The chord is
If we stick to the [[5-limit]], which traditional tonal harmony mainly concerns, the augmented sixth represents both [[125/72]] and [[225/128]]. It is treated as a rare and special dissonance, especially when used on the sixth degree. The chord is


* (Meantone) 1 – 5/4 – 3/2 – 125/72 with steps 5/4, 6/5, 75/64
* (Meantone) 1 – 5/4 – 3/2 – 125/72 with steps 5/4, 6/5, 75/64.


Note the ~125/72 is simultaneously ~225/128.  
Note the ~125/72 is simultaneously ~225/128, and the ~75/64 is simultaneously ~125/108.  


However, most [[meantone]] tunings has the augmented sixth placed near [[7/4]]. In the historically-prevalent [[quarter-comma meantone]], for example, it is tuned only a few cents shy of a just 7/4, so the meantone German sixth chord can be considered to approximate the [[harmonic seventh chord]]:  
However, most [[meantone]] tunings has the augmented sixth placed near [[7/4]]. In the historically-prevalent [[quarter-comma meantone]], for example, it is tuned only a few cents shy of a just 7/4, so the meantone German sixth chord can be considered to approximate the [[harmonic seventh chord]]: