Marvel chords
Marvel chords are essentially tempered dyadic chords tempered by the marvel comma, 225/224. The marvel triad, aka marvel augmented triad, or septimal augmented triad, is a marvel chord which in close position consists of two major thirds of approximately 5/4 and a supermajor third of approximately 9/7, or in other words a 5/4-5/4-9/7 chord, which closes at the octave since the marvel comma, 225/224, is tempered out. In meantone this triad consists of two major thirds and a diminished fourth, the classic augmented triad of the meantone era. It can also be described as a marvel-tempered version of a 1-5/4-14/9 chord.
Another marvel essentially tempered triad is the 5/4-9/8-10/7 chord and its inversion, which means the marvel tempering of 1-5/4-7/5 and 1-10/7-8/5. There are also marvel tetrads: the 5/4-9/8-10/9-9/7 chord and its inversion, temperings of 1-5/4-7/5-14/9 and 1-5/4-8/5-16/9; the 5/4-9/8-8/7-5/4 chord and its inversion, temperings of 1-9/8-7/5-7/4 and 1-5/4-7/5-8/5; the 5/4-9/8-5/4-8/7 chord, the tempering of 1-5/4-7/5-7/4; and the 9/8-10/9-9/8-10/7 chord, the tempering of 1-9/8-5/4-7/5. There are also two marvel pentads, the 9/8-10/9-9/8-5/4-8/7 and its inverse, which are the temperings of 1-9/8-5/4-7/5-7/4 and 1-9/8-5/4-7/5-8/5.
The 9-limit marvel chords number triads: 3, tetrads: 6, pentads: 2, for a total of 11.
Equal temperaments with marvel chords include 19edo, 22edo, 31edo, 41edo, 43edo, 50edo, 53edo, 72edo, 84edo, 94edo, 103edo, 166edo and 197edo.
Marvel triad