devil's advocate..Montal

[Richard Moody]

> ----------
> > From: Jim Coleman, Sr. <pianotoo@imap2.asu.edu>
> > To: Richard Moody <remoody@easnet.net>
> > Cc: pianotech@ptg.org
> > Subject: Re: devil's advocate..Montal
> > Date: Thursday, March 19, 1998 8:21 PM
> > 
> > Hi Richard:
> > You made one comment about the 3rd-6th test where you said that if
> the
> > 3rd and the 6th were the same then the included 4ths would be
> narrow.
> > IMHO, the 4th would be pure even with an uneven inharmonicity
> balance 
> > because the same test partial is involved in all three intervals.
> for 
> > example, if you were testing the A3-D4 4ths, with the F3-A3 3rd
> compared
> > with the F3-D4 6th, the coincident partial where the beats first
> occur is
> > at A5 for all three intervals. Making the 6th beat 1 bps faster
> than 
> > the beat of the 3rd is our standard test for a 4th which should
> usually 
> > beat 1 bps.
> > 
> > Jim Coleman, Sr.
> 
> You are  right of course.  I said  " I
> found that if this third and the sixth beat the same, or the sixth is
> ever so slightly faster, then the fourth is wide.  If the fourth is
> pure, then the sixth will beat slower than the third."
> 
> 	This is wrong to the the math, the if the fourth is  pure the sixth
> should should beat the same as the third. .
> 	
> 	Not knowing this and hearing it for the first time, it sounded like
> the third and sixth were beating the same when I had the fourth a
> little sharp, (OR thought I had)  So lowering the top note to make
> the fourth pure, the sixth slowed down. I guess that's why it sounded
> slower than the third.  I will have to check again tomorrow.  Or
> maybe inharmonicity is throwing things off.  F is the last note in
> the tenor in this piano.  Cute little no-name upright.  Meissner,
> Milwaukee
> 	Yes the charts in Braid White show the sixth beating .99 faster than
> the third and the fourth beating at .99 per second. (6.93--7.92)
> ...  Maybe this piano is "off" but  to get a beatless A octave, the
> lower third seems beating less than the tenth.
> 
> NEXT DAY: Upon closer and longer listening, now the sixth and fourth
sound
> like they should. Or they are close enough not to tell.  If anything the
> third sounds slower.  But not to worry, the only person who can tell is
> another tuner better than I. But why the heck does the third sound
slower?
>   Well it apprears that the A sustain is less than the F or the D. This
> could give the illusion of a slower F--A third.  If excuses were straws,
> I'd be lost in a haystack. 
> 	Another test for accuracy, especially for pure intervals, (and a lot of
> fun), tune the middle string to whatever interval.  Now mute the middle
> string and tune the outside string to the same.  Now compare the two
> strings.  Are they at unison?? This is a good one  for consistency of
> octaves. Speaking of devil's advocate, this might be a good test to see
if
> the machine can "beat" the ear. 
> 
> Richard Moody 
>