Seven limit tetrads

The two seven-limit tetrads are the otonal, which in close position is 1-5/4-3/2-7/4, and the utonal, 1-6/5-3/2-12/7, with scale steps 5/4-6/5-7/6-8/7 and 6/5-5/4-8/7-7/6 respectively. These are the two most basic chords of seven-limit harmony, and form a cubic lattice.

More seven-limit tetrads can be found here: xenharmonic.wikispaces.com/Chord+names