This utility generates Scala tuning files for rank 2 regular temperaments. It is primarily intended for users that do not have access to Scala itself (as Scala can do everything that this simple tool does, and much, much more!)
Explaining what a rank 2 regular temperament is, and how to use one, are quite outside the scope of these instructions! If you're not sure, the Xenharmonic Wiki is a good place to start.
There are no presets here; you will need to supply the period and generator yourself. Sources include the xenwiki, Graham Breed's temperament scripts and really big list, Paul Erlich's 'A Middle Path' paper, the Xenharmonic Alliance Facebook group, and of course, Scala itself.
Period and generator may be entered in the following formats:
The "show MOS sizes" button will (based on the current preiod and generator) show a list of scale sizes which are MOS (have at most two interval sizes). Any MOS sizes with steps smaller than the indicated cents value will be ignored (set this to 0 if you don't want to use this feature). Currently the MOS size search stops at 400 (sorry Gene Ward Smith :) ). Note that the current scale size does not matter when clicking this button. nor does the MOS list affect the scale output in any way. It is simply a reference which may assist you in choosing a scale size.
When you click the "generate scale" button, the scale will be generated according to the current period, generator, and scale size, and displayed in Scala .scl format. Typically you will want to copy the output, from the first "!" (inclusive) to the end, paste it into a text editor, and save it as a file with extension ".scl". If you wish, you may edit the first line (! r2-rt.scl) to match the filename you choose - but be sure to keep the "!" at the beginning of the line. You may also edit the description line (which does not begin with "!").
When generating a scale, be sure to look carefully at the description line, which shows the period and generator used. Make sure the values shown are what you intended! Sometimes the program may not parse your input in the way you expect. For example, if you entered 1200 for the period, you probably intended 1200 cents, but because there is no decimal point, this will be interpreted as 1200/1 (12274.582 c). The resulting scale file will be valid, but will probably not sound like you expected.
Note: while the period and octave are equivalent in many regular temperaments, there are a fair number of RTs that have multiple periods per octave! Do not be alarmed by this. Simply enter the period and generator as any other. Be aware that the scale size and MOS sizes will refer to notes per period, NOT per octave. So, for example, the blackwood decatonic scale (10 notes per octave; p=1\5, g=1\15) is actually a 2-note scale here, because blackwood has 5 periods per octave (2*5=10). The resulting .scl file should work properly in any program that correctly implements the file format.
It should be noted that while this utility is designed for rank 2 temperaments, it can easily be used to generate rank 1 temperaments (EDOs / ETs) as well. For example, to generate 19edo, use 2 as the period, 1\19 as the generator, and 19 as the scale size.
Change log
0.1.1 (2014-08-26) - fixed bug in MOS list, added word wrap for long lists
0.1 (2014-08-18) - initial release
Please send bug reports or feature requests to aaannnn@hotmail.com, where aaa = (letters 19, 16, 20) and nnnn = (5^5).