1156/1155 is a 17-limit no-13 superparticular comma measuring about 1.41 cents. It may be properly described as the septendecimal quartertones comma, since it is the difference between 34/33 and 35/34, the two 17-limit quartertones.
In terms of commas, it is the difference between the following pairs:
- 289/288 and 385/384
- 442/441 and 715/714
- 561/560 and 1089/1088
- 595/594 and 1225/1224
- 936/935 and 4914/4913
It factors into the following pairs:
Tempering out this comma results in 35/33 being split into two equal parts, each representing 34/33~35/34, and enables the related essentially tempered chords. If 9801/9800 is also added to the comma list, the quartertone above becomes literally a quarter of 9/8 and is located right between 33/32, the undecimal quartertone, and 36/35, the septimal quartertone.