There may be more on this page one day. Like an explanation of what these MOS things are. At the moment, though, I'm showcasing my applet for MOS calculations. Here it is:

I should really provide instructions. Instead, I'll stick with telling you how to use it. The left-hand column is a frequency ratio. In the right-hand column are two ways of specifying an octave based MOS scale where the generating interval approximates that ratio on the left. The octave is specified in terms of the intervals x and y. The fraction lower down shows the size of the generating interval and octave in terms of scale steps.

Right at the bottom is the ratio of the intervals x and y on a pitch scale that makes the generating interval exactly the frequency ratio on the left. In the middle are a number of equal temperaments that fit the pattern selected. they are chosen by taking a value for the smaller interval, and finding the size if the larger that best approximates the frequency ratio. The numbers are the steps (of the temperament, not scale steps) in the intervals x, y and the octave, as expected.

There are left and right buttons you can use to choose less or more complex scale types based on the same frequency ratio. That means navigating the MOS scale tree. I think this site gives the mathematical background on that. For the musical connection, have a look at The Wilson Archive. The ratio can also be changed. Change the numbers, and press return for the update.

I plan to do more work on MOS-related programs. Also, I'll put the source code up as soon as I can be bothered. If you want it beforehand, you can e-mail me. An applet that doesn't assume perfect octaves might arise,