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<DIV dir=ltr align=left><SPAN class=429331507-22082008>"There will be no point
in tuning the proposed bourdon of 75t, <BR>certainly not in any any conventional
sense, because any partial we <BR>normally talk about will be way below the
audible range. I would <BR>guess such a bell would have a nominal of about
180Hz. All one will <BR>hear is a low-pitched tuneless crash."<BR></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>That's an interesting
one, which I do not believe.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>For starters, 180HZ is
over 3 octaves above a 32Ft pipe.</SPAN><SPAN class=429331507-22082008><FONT
face=Arial size=2></FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>The human auditory range
is said to extend to 16HZ, which just happens to be the bottom of a 32ft
stop.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>I have a speaker system
that extends to about 20, (IMF TLS80's, fully characterised).</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>I have done some
experimentation with very low frequency sound, years ago and not aimed at
detecting pitch.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>I do remember that pitch
can be discerned, although it takes longer and I suspect there is loss of
accuracy.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>There are some wonderful
low frequency organ sequences in "Symphony Antarctica" a cadence of almost ever
decreeing frequency notes, most impressive, a more sensual than audible
experience.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2>To suggest the effect could be generated by just playing the same note
repeatedly, no way!</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2>Its probably true that most of us would be quite unable to pitch an
isolated single low frequency sound but the ear is rather good at detecting the
difference between a sequence of notes.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2>Its fact that very few people ever hear extreme low frequencies, as
an isolated sound, intended to be heard as such.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2>Most sound reproducing systems give up some ware between 70 and 100HZ,
and few "hi-fi" systems get much below 50. </FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2>Since almost all low frequency sound is unwanted noise most of us learn
to "turn off" listening to it.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2>Appreciating low frequencies is something I had to learn (years before I
learnt to ring).</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>Some organs actually have
a 64ft, Just over 8Hz, Liverpool Cath for one, although I have no idea
why.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>A demonstration of 12HZ
at a sound pressure of 100dB was to me totally inaudible.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>It went like this, a
friend of mine, Rex Baldock and a sound expert had a house with a folded
18Ft horn speaker built under the floor. I, with others were invited in
and asked if we could hear anything, none of us could.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>Rex then pulled out a
"Daw" sound level meter and switched it on.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>inexplicably it read
100dB.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>He then unfolded a sheer
from the Telegraph and placed it over the floor grill where sound from the horn
entered the room.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>It lay flat about 1" from
the floor, apparently suspended on nothing.</SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008>Rex then turned down the
Amplifier, the paper descended and the sound meter fell back to about 50, all
with no apparent change in sound levels within the
room.</SPAN></DIV></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2></FONT></SPAN> </DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2>Could I have an example of an organ with an open, or even a
stopped 32 reusing pipes?</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial size=2>I
have crawled round a number, over 50 years and have never noticed
one.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2>Rod.</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2>PS</FONT></SPAN></DIV>
<DIV dir=ltr align=left><SPAN class=429331507-22082008><FONT face=Arial
size=2>If someone wanted to build a huge pipe rank would not 96 make more sense
than 64 as it could be over blown to produce the loudest ever
32?</FONT></SPAN></DIV>
<DIV dir=ltr align=left><FONT face=Arial><FONT size=2><SPAN
class=429331507-22082008>An open 64' could be downright dangerous as
it can generate human body resonance frequencies (7 to 12HZ?)</SPAN>.<SPAN
class=429331507-22082008></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> 21 August 2008 22:00<BR><B>To:</B>
bellhistorians@yahoogroups.com<BR><B>Subject:</B> [Bell Historians]
Carillon<BR></FONT><BR></DIV>
<DIV></DIV>
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<P>There will be no point in tuning the proposed bourdon of 75t, <BR>certainly
not in any any conventional sense, because any partial we <BR>normally talk
about will be way below the audible range. I would <BR>guess such a bell would
have a nominal of about 180Hz. All one will <BR>hear is a low-pitched tuneless
crash.<BR><BR>However, this is a fantastic cost saving measure, because the
bottom <BR>half dozen or more keys on the keyboard or clavier can all play on
<BR>the same bell, and no-one will know any different. (This is an old
<BR>organ-builders trick for 32 foot stops.) To avoid each of the keys
<BR>producing an identical tuneless crash, each hammer could hit the bell <BR>at
a different point moving up from the lip towards the waist.<BR><BR>To have the
bottom nine semitones (i.e. everything with a nominal of <BR>less than 300Hz)
all play at different points on the same bell will I <BR>estimate save about 315
tonnes of metal. With enough bells, arranged <BR>artistically, no-one will think
to count how many there are.<BR><BR>Bill H<BR><BR></P></DIV><!--End group email --></BODY></HTML>
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