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<DIV dir=ltr align=left><SPAN class=035445309-06122007>Bill Hibbert's most
interesting response, to me poses the question: </SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007>Why have thick trebles
with all the tuning problems associated with a variable casting
scale?</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2>Is it a matter of acoustic power?</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2>Possibly but:</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2>The days when the absolute maximum sound and carry from a peal of bells
was required are long passed, and a huge amount can be done with louver design
and bell chamber internal design to increase output, should it ever be
needed.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2>Is it sound balance?</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial size=2>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2>Possibly but:</FONT></SPAN></DIV></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2>The sound output from a bell is governed by the amount of energy the
clapper imparts.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2>It is not that difficult to turn that down on larger bells, although I
appreciate it is more complex than simply fitting a smaller clapper,
because the dynamic of the way the energy is imparted must generate the correct
intensity from each partial.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2>Is it ringing dynamics</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial size=2>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2>Possibly but:</FONT></SPAN></DIV></FONT></SPAN><SPAN
class=035445309-06122007><FONT face=Arial size=2>Combinations of "hang
out", counter weight, wheel size and clapper dynamics can enormously vary
the dynamics, to give a small bell big bell dynamics.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2>One only has to look at the improvement in mini rings to see that
demonstrated.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007><FONT face=Arial
size=2>What other considerations are there? </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=035445309-06122007></SPAN><FONT face=Arial
size=2><SPAN class=035445309-06122007>Tradition?, Credibility, or something I
have completely overlooked?</SPAN></FONT></DIV>
<DIV dir=ltr align=left><FONT face=Arial size=2></FONT> </DIV>
<DIV dir=ltr align=left><FONT face=Arial><FONT size=2><SPAN
class=035445309-06122007>.</SPAN></FONT></FONT></DIV><BR>
<DIV class=OutlookMessageHeader lang=en-us dir=ltr align=left>
<HR tabIndex=-1>
<FONT face=Tahoma size=2><B>From:</B> bellhistorians@yahoogroups.com
[mailto:bellhistorians@yahoogroups.com] <B>On Behalf Of </B>Bill
Hibbert<BR><B>Sent:</B> 06 December 2007 09:43<BR><B>To:</B>
bellhistorians@yahoogroups.com<BR><B>Subject:</B> [Bell Historians] Stretch
tuning<BR></FONT><BR></DIV>
<DIV></DIV>
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<P>Responses to various posts and questions:<BR><BR>> CSZ's question on the
history of stretch tuning:<BR>Stretch tuning (of e.g. 20 cents per octave or
more) was the common <BR>practice for higher numbers in the 18th and 19th
centuries. Taylors <BR>in particular used a huge amount of stretch in peals such
as St <BR>Pauls Cathedral and the old Worcester 12. Whitechapel (as RO's
<BR>posting of some while back showed) were tuning strike notes, not
<BR>nominals, until the 1920s which guarantees stretch if the trebles <BR>are
thicker than the tenors. Stretch tuning stopped with the <BR>introduction of
true-harmonic tuning, but as Andrew Higson says, <BR>Taylors re-introduced it
from the early 1950s until the 1970s. I am <BR>aware of one stretched peal from
Whitechapel from this period <BR>(Cornhill 1958) but perhaps there are others I
haven't come across.<BR><BR>> Rod's comparison of bell stretch with piano
stretch:<BR>In pianos, stretch tuning arises because the upper partials and in
<BR>particular the 2nd harmonic are slightly sharp due to the stiffness <BR>of
the piano string as it crosses the bridges. As a result, if the <BR>octaves in a
piano are tuned for zero beats, they will be slightly <BR>stretched. The amount
of stretch depends on the quality of the <BR>piano's construction; high quality
grand pianos need less stretch <BR>than cheap uprights. As Rod says, a few cents
in the octave is the <BR>typical amount.<BR><BR>Stretch in bells arises for a
completely different reason; <BR>compressed upper partials (which occur in
thick, heavy bells) <BR>flatten the strike note. The effect is large: 25 or 30
cents is not <BR>uncommon. Therefore, in a peal with thick trebles and thinner
<BR>tenors, if the trebles are not stretched some people will say the
<BR>trebles are flat, or dull sounding. I wrote an RW article on this a
<BR>while ago, I don't have the reference with me. My PhD research has <BR>now
proved the effect beyond reasonable doubt and provides a way to <BR>calculate
the effect, though you'll have to wait until it's <BR>published to read the
details. Investigation of half-a-dozen <BR>stretched 19th and 20th century
twelves gives satisfactory <BR>correlation between theory and
practice.<BR><BR>Stretch tuning is not at all to everyone's taste. In fact,
there are <BR>two modes of pitch perception experienced by different listeners,
<BR>and sometimes the same listener under different circumstances. Most
<BR>listeners hearing bells rungs close together in changes experience a
<BR>holistic effect (the strike note, shifted by the upper partials). <BR>Other
listeners, especially bell tuners, hear the individual <BR>partials,
particularly if one or two bells only are being rung.<BR><BR>> Richard Offen
and St George's Perth:<BR>Richard's comment that the trebles are thin is an
important clue. If <BR>this is so, the strike notes will not be flattened to the
same <BR>degree as for thick trebles. It sounds as if stretch has been
<BR>applied in a formulaic way to these bells when it was not needed. <BR>Tuning
figures (especially the octave nominals) would settle the <BR>matter. Plus,
Richard used to be a bell tuner ...<BR><BR>> CSZ quoting from Frederick
Meyer, on carillon stretch:<BR>This was an interesting account, which I had not
heard before. In <BR>carillons, of course, the little bells are not thickened up
as they <BR>would be for change ringing, and so the pitch shifts are much less.
<BR>Another experiment written up in the thesis investigates which <BR>partials
determine pitch in bells. In little bells (e.g. the top end <BR>of carillons),
the prime and/or hum take over from the nominal.<BR><BR>Cheers,<BR><BR>Bill
H<BR><BR></P></DIV><!--End group email --></BODY></HTML>
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