Negative Inharmonicity

[Robert Scott]

Allan wrote:

>Hi everybody,
>
>I ran into something interesting today and thought that I would throw it out
>to see where the discussion leads.  While tuning a Knabe console, I noticed
>that when then fourth patrial of F3 is tuned to F5 then F6 is compared you
>find that F6 if a couple of cents flat, ie. negative inharmonicity.  BTW, yes
>this is while taking the meaurements for an FAC tuning.  This note is on the
>treble bridge and has wound strings.  I remember this issue coming up a
>couple of years ago in the journal and perhaps one of you remember the
>reference and such.  Any good explanations out there for this kind of
>measurement?
>
>Thanks,
>
>Allan
>
>Allan L. Gilreath, RPT
>Gilreath Piano & Organ Co.
>Berry College
>Gilreath@aol.com
>

   The string in question may very well have negative inharmoncity for some
partials, but it is not clear from your description that this is what you have.
When you say that you find F6 to be a little flat, do you mean F6 as the
8th partial of F3? or F6 as the 2nd partial of F5?  And flat compared to what?

   -Bob Scott