11/10
| Interval information |
undecimal submajor second
reduced
[sound info]
11/10, the large undecimal neutral second or undecimal submajor second, is an interval favored by Ptolemy. Coincidentally, the interval between the most common tuning frequency (A440) and the second most common AC electrical frequency (50 Hz) is exactly 44/5, or three octaves above an 11/10.
