1/2 cent difference on unison

[Richard Moody]

----------
> From: Jim Coleman, Sr. <pianotoo@IMAP2.ASU.EDU>
> To: Don <drose@dlcwest.com>
> Cc: pianotech@ptg.org
> Subject: Re:1/2 cent difference on unison
> Date: Thursday, January 29, 1998 2:11 PM
> 

> 
> For just a minor correction due to further research. This
phenomenon of 
> the complete 3 string unison giving off a pitch lower than any of
the 3
> single strings individually is primarily observable in the 5th and
6th 
> octave only.

Can this be demonstrated aurally? I still on occasion will tune say
G6, get the double tenth I wanted from D#4, tune out the unison, then
find my dlb 10th was now slower than the beginning.  The first string
must have been knocked down a hair when tuning the second string, and
isn't caught until the unison is completed and checked again.  So one
learns to tune a little higher... hmm  I wonder...   It would happen
all the time then, but since you don't tune all of the treble notes
then it wouldn't happen all the time, and if you do have to tune all
of the treble notes you wouldn't be fine tuning. 

Richard Moody  .  

> 
> I have measured cases
> where the difference is as much as .9 cents. Then there are cases
where the
> difference is negligible even in that area. I don't think anyone
yet has a
> firm explanation for it.
> 
> Jim Coleman, Sr.
> 
> On Thu, 29 Jan 1998, Don wrote:
> > 
> > Who has demonstrated this and how? 
> > Don Rose, B.Mus., A.M.U.S., A.MUS., R.M.T., R.P.T.
> > "Tuner for the Centre of the Arts"
> > drose@dlcwest.com
> > 3004 Grant Rd.
> > REGINA, SK
> > S4S 5G7
> > 306-352-3620 or 1-888-29t-uner
> >