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<DIV>In a message dated 5/13/2004 9:08:12 PM Pacific Standard Time, sbirkett=
@real.uwaterloo.ca writes:</DIV>
<BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue =
2px solid"><FONT face=Arial>and Dale:<BR>>May I submit that the I=
nner friction of felt has always been a <BR>>fairly esoteric & =
small consideration to the discussion of hammers <BR>>even though it is a=
know factor & frankly to me personally not very <BR>>useful.<BR><BR>=
I disagree. I think this phenomenon is actually the contributing <BR>factor =
which will turn out to be MOST critical and absolutely <BR>essential to felt=
hammers being able to produce the sound we have <BR>come to expect from the=
piano. Without it the sound would probably be <BR>considered wrong and un-p=
iano-like. I have some ideas why, and how, <BR>but won't speculate yet on wh=
at we may find as we will soon be <BR>extending the felt research project to=
consider hammer design and <BR>hammer-string interaction.<BR><BR>Stephen</F=
ONT></BLOCKQUOTE></DIV>
<DIV> <FONT size=3><STRONG>Hi Stephen.</STRONG></FONT></DIV>
<DIV><FONT size=3><STRONG> I'm more than curious about what&nb=
sp; you're doing in the way of experiments in this regard. Hope there i=
s more insight at some point.</STRONG></FONT></DIV>
<DIV><FONT size=3><STRONG> My above statement should be taken =
as stated with thefollowing clarification that until now, the discussion of =
internal friction has been known but not very useful so far in any discussio=
n I've participated in. I would hope that some clarity on the subject would =
</STRONG></FONT><FONT size=3><STRONG>give some practical insight=
s on how it relates to tonal production & hammer design or what imp=
act this may have on hammer design changes if any. </STRONG></FONT></DIV>
<DIV><FONT size=3><STRONG> Many have brought up the fact in va=
rious discussions but with no correlation as to how we should think about it=
or how it affects voicing or anything else for that matter. Know what I mea=
n now?</STRONG></FONT></DIV>
<DIV><FONT size=3><STRONG> I suspect internal friction &=
amp; the springiness or stiffness of the felt we all talk about are clo=
sely related I just don't know how to think about it. Yet.</STRONG></FONT></=
DIV>
<DIV><STRONG><FONT size=3> My best guess is that tension & compr=
ession alters or enhances the internal friction of wool felt.</FONT></S=
TRONG></DIV>
<DIV><STRONG><FONT size=3> Regards, </FONT></STRONG></DIV=
>
<DIV><STRONG><FONT size=3> Dale Erwin</FONT></STRONG></DIV>
<DIV> </DIV>
<DIV> </DIV>
<DIV><FONT lang=0 face=Arial size=2 FAMILY="SANSSERIF" PTSIZE="10"=
>Erwins Pianos Restorations <BR>4721 Parker Rd.<BR>Modesto, Ca 95357<BR>209-=
577-8397<BR>Rebuilt Steinway , Mason &Hamlin Sales<BR>www.Erwinspiano.co=
m</FONT></DIV></BODY></HTML>