Mudcat Café message #345521 The Mudcat Café TM
Thread #19748   Message #345521
Posted By: GUEST,Bruce O.
22-Nov-00 - 11:31 PM
Thread Name: Modes for Mudcatters: A Synthesis Primer
I've upgraded the stressed note-key-mode software on my website to support semitone sequences. Instead of the W and H that Peter T. used in the first note above I use 2 and 1. So W (whole step) is 2 semitones and H (half step) is one semitone. I can then use 3 and higher numbers that are needed for other modes. The numbers, rather than letters, for semitone sequences lets you do any mode, and you can check it, because the sum of the all the digits of a semitone sequence must equal 12. Lydian is then 2221221 and Ionian is then 2212221, etc. (Cyclic permutation of 2212221 gives semitone sequences of the 7 'greek' modes)

About a year ago some said in this forum that there were 180 modes in Turkish music and they all had names. I've now got that many modes among the 6504 British Isles tunes coded on my website. They don't all have names, but they don't need them, because my mode# identifies them uniquely (and you can get the actual scale relative to the keynote from it by simple math- no tables needed).

The (numerical) semitone sequence is also a unique mode identifier, but over 95% of the digits are 1's or 2's and in a long list of semitone sequences the numbers all start looking about the same (almost as bad as reading long binary numbers). The tunes in my COMBCOD2.TXT file vary from a 3 note scale- Mode# 10, semitone sequence 228, to an 11 note scale- Mode# 2046, semitone sequence 21111111111. That last one demonstrates the difficulty in using semitone sequences for mode identifiers. How long does it take you just to count up the number of 1's in it? 2046 is a lot easier to deal with (and 2047 is the maximum possible, a 12 note scale)

See the tune code files and program at: