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<DIV><STRONG><FONT color=#008080 size=2>JD, can you please comment on hex
core?</FONT></STRONG></DIV>
<DIV><STRONG><FONT color=#008080 size=2></FONT></STRONG> </DIV>
<DIV><STRONG><FONT color=#008080 size=2>-Jason Kanter</FONT></STRONG></DIV>
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<DIV style="FONT: 10pt arial">----- Original Message ----- </DIV>
<DIV
style="BACKGROUND: #e4e4e4; FONT: 10pt arial; font-color: black"><B>From:</B>
<A title=JD@Pianomaker.co.uk href="mailto:JD@Pianomaker.co.uk">John
Delacour</A> </DIV>
<DIV style="FONT: 10pt arial"><B>To:</B> <A title=pianotech@ptg.org
href="mailto:pianotech@ptg.org">Pianotech List</A> </DIV>
<DIV style="FONT: 10pt arial"><B>Sent:</B> Tuesday, October 03, 2006 3:59
PM</DIV>
<DIV style="FONT: 10pt arial"><B>Subject:</B> Re: Formulae for String
Calculations</DIV>
<DIV><BR></DIV>
<DIV>At 11:25 am +0200 3/10/06, Ric Brekne wrote:</DIV>
<DIV><BR></DIV>
<BLOCKQUOTE cite="" type="cite">My question is, whether or not spreadsheets
and string calculation programs generally take into account these end
lengths for basic scaling work ? How important is it to gain the extra
accuracy in taking into account these endlenghts, hex/round... etc factors
?</BLOCKQUOTE>
<DIV><BR></DIV>
<DIV>So far as calculating tension etc., the matters I dealt with in the web
page, not at all. As I explained in the last paragraph, the tiny
differences involved are not significant in the basic calculations. But
as regards the tonal quality of the string, inharmonicity etc. these things do
matter. We aim to start the copper about 8 to 10 mm from the bridge pin
and leave about 15mm bare at the top bridge. If I'm working from a
rubbing I have taken myself then I will reduce these figures. The first
two pictures below illustrate "Erard whipping" and "Steinway whipping", both
of which lend greater purity or clarity to the tone. Unless we are asked
for unwhipped strings, which we never are, we use the Erard or Bechstein style
of whipping on all bichords and trichords. The Steinway syle of whipping
takes more time and we charge extra. Steinway stopped bothering to whip their
strings some time before WW2 but Bechsteins have always been whipped.</DIV>
<DIV><BR></DIV>
<DIV>The third picture shows the end of one of our typical double-covered
strings, which, as you see, has a shorter shoulder than is found on most
makers' strings. This also makes a slight difference to inharmonicity,
as does the ratio of the two covers.</DIV>
<DIV><BR></DIV>
<DIV>So the answer in brief is that these things are irrelevant in your "basic
scaling work" but in combination, including other factors too, make a huge
difference to the quality of sound produced by the strings.</DIV>
<DIV><BR></DIV>
<DIV>JD</DIV>
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