The ornament in question clearly starts with an appoggiatura, which ought to be held about half the value of the main note. Then comes a trill, as fast as you can go. Finally, the last note (the main note) should be reached a little bit before the next beat, so it sounds like a main note. The way JSB notated it in his table gets all of this across. One thing it doesn't get across is that the number of vibrations in the trill will depend on the tempo as well as the facility of the performer.
This assessment is based on 29 years of experience playing the harpsichord. There are many examples in Francois Couperin's harpsichord works of _written out_ ornamental passages where the note values don't add up, and even more examples of misguided modern editors who tried to correct them. I don't regard these sorts of discrepancies as errors. They're manifestations of the impossibility of notationally conveying the exact way of realizing any ornament in a way that fits all possible situations. --Don Simons > -----Original Message----- > From: [EMAIL PROTECTED] [mailto:tex-music- > [EMAIL PROTECTED] On Behalf Of Bob Tennent > Sent: Friday, December 28, 2007 9:12 AM > To: tex-music@icking-music-archive.org > Subject: [TeX-Music] correcting J.S. Bach bug > > Hi all. It's not every day one gets a chance to correct a mistake by > JSB! I sent a colleague a link to Bach's "Explication": > > http://icking-music-archive.org/scores/bach/explica.pdf > > He pointed out that the last two examples don't "add up". This is not > the fault of Jean-Pierre Coulon, who faithfully typeset Bach's notes: > > http://www.jsbach.net/images/ornaments.jpg > > But now the question for you is: what did Bach *intend* to write? My > colleague thought the first note should be shortened, but my opinion is > that that note is an appogiatura and should take half the apparent note > value; rather, the four "trill" notes should be 64ths instead of 32nds. > What say all of you? > > Bob T. > _______________________________________________ > TeX-music mailing list > [EMAIL PROTECTED] > http://mailman.daimi.au.dk/mailman/listinfo/tex-music _______________________________________________ TeX-music mailing list [EMAIL PROTECTED] http://mailman.daimi.au.dk/mailman/listinfo/tex-music