Inharmonicity - so what actually causes it ?

conrad hoffsommer hoffsoco@martin.luther.edu
Thu, 13 Aug 1998 09:07:08 -0500 (CDT)


>In a message dated 8/13/98 7:27:30 AM, aland@casa.co.nz wrote:
><<Dear Inharmonicity,
>I read all your knowledgeable definitions - OK - but for me the real
>questions are:
>
>1) WHAT are the specific properties of the piano string and scaling
>components etc. that actually CAUSE it ???
>

The thickness and therefore stiffness of the steel wire prevent the
vibrations of the string from being pure sinesoidal, which would be
necessary for zero inharmonicity.  

The length/thickness ratio of the strings varies considerably from #1 to
#88. Example might be a concert grand with #88 about 2"/.031 or 64:1 and #1
about 80"/.198" or 404:1 [completely ignoring core/winding differences]

If you had the 64:1 ratio for #1 the "string" would be 1¼" thick. Not very
flexible. High inharmonicity. BTW, I would not make coils on _that_ tuning
pin by hand...

Conrad




Conrad Hoffsommer                      Office - (319) 387-1204
Luther College                         Music Dept Fax - (319) 387-1076
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