<HTML>In a message dated 11/20/00 7:03:56 AM Central Standard Time, A440A@AOL.COM writes: <BLOCKQUOTE TYPE=CITE style="BORDER-LEFT: #0000ff 2px solid; MARGIN-LEFT: 5px; MARGIN-RIGHT: 0px; PADDING-LEFT: 5px">  <<  I think Bach wrote this as he did to display the usage of the highly tempered key of C#.  The alternating notes of the harmony don't perceptibly "beat",  they are too fast and never struck together.      Perhaps an easier excercise would be to play the prelude in C in the key of C# on a well tempered piano.  This will show how bad the "wrong" key will sound.  In ET there will be no difference, but in a Werckmeister or something like it,  the C prelude will sound very poor in the key of C#. >></BLOCKQUOTE> Owen Jorgensen often used this very same example in his lectures.  Many pianists are able to transpose literature at will.  When the first prelude in C is played on a WT in C#, it sounds strained and the harmony is harsh.  When the prelude in C# is played in C, it sounds dull and lifeless. These issues are very elementary yet it seems that few people know about them.  Composers chose a key to write in for a *reason*, they didn't just decide on the basis of pitch or for some vague unexplainable intuition or at random.  You can have the same experience with just about any popular music too.  Try playing The Music Box Dancer in a WT in the key it was written, C.   Then try it in C#.  You'll get the same inappropriate effect.  If however, you went up another half step to D or down from C a full step to Bb, the piece will sound just fine. Try Rodgers & Hammerstein's "If I loved you" from Carousel in the proper key of Db in a mild WT such as a Victorian or even Thomas Young.  You'll get lots of singing tone from the arpeggios (broken chords) and wide 10th and 17th intervals.  The melodic line carries well with the larger 2nds and 3rds and high leading tones.  Transpose it down to C and the piece sounds dead and dull. Once again, ET negates all of these distinctions and provides only one neutral sound which in itself is inappropriate if only slightly so.  This is the reason I never choose to tune it.  I know of no music whatsoever that requires no distinction from one key to the next and at the same time provides inappropriate sounding harmony to virtually everything. Bill Bremmer RPT Madison, Wisconsin</HTML>