Okay Colin, and all the other celebrities, here it is, an intelligent text on what we discuss:
An Aspect Of Harmony In Music of Johann Sebastian Bachby Frans Oort
International Symposium on Johann Sebastian Bach
University of Oxford, 17 and 18 December 2001
http://vsl.co.at/upload/users/57/An_aspect_of_harmony_in_music_of_Johann_Sebastian_Bach.pdfRead it! It is reduced to one example about Bach's harmony and temperament. Just read it thru, ignore for the moment what you don't understand, there is certainly a lot you will understand right away. For example:
"Did Bach use a “correct” tuning in a certain system (temperament), or did he just tried to find the one which was the best for the situation at hand?" Bach seemed simply to have this talent, to tune an instrument in a way who permittet him to be-bop thru all keys without sounding wrong. Bach was a guy living on his own musical level, I mean, just playing his music is one thing, but he composed that music.
If you have a digital piano where you can chose the temperament, simply dial Werckmester, or Kirnberger, for example over the root of D, and play some music who modulates thru all degrees in a diatonic fashion, just diatonic, nothing else. This is the best way to hear and learn what "Affekt" the tonalities produce. The tuning Bach used was not Werckmeister, nor Kirnberger or any other tuning we know of. And as said, it is not known what temperament Bach used and tuned his instruments by. It is only assumed that it was a temperament very similar to Werckmeister's temperament.
Kirnberger was possibly a pupil of Bach, and he wrote some scientific texts about diatonic and temperament, one is titled: “Die Kunst des reinen Satzes in der Musik” 1771. The history of the tuning and temperaments is long and complex. The equal temperament was already published at the time of Bach, but was never applied on a keyboard, and not on a ensemble. For a long time it was also assumed that "well tempepred" is the same as "equal tempered" which is not true.
Notice, when people sing, in choir music and without instrumental accompany, then we are confronted with a whole other phenomenon. Humans are like birds, when they hear an instruments, they adjust to the temperament of this instruments with ease and in no time, just like the male "Blackbird"
http://en.wikipedia.org/wiki/Blackbird
http://de.wikipedia.org/wiki/Bild:Turdus_merula_distribution.jpg
in my garden adjusts to the music they hear coming out of my window, you can make them sing Raga's if you like, or use them as royalty free melody generator. When there are no instruments, human sing most often, and completly natural in a pure tuning and temperament. That's Bach, and only he knew what he was doing… maybe not even he fully knew, but he simply did it!
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