<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; = charset=us-ascii"> <META content="MSHTML 6.00.2800.1126" name=GENERATOR></HEAD> <BODY> <DIV><SPAN class=804302620-26052003>With a light bedding, I guess that = under forte blow there is a distortion that travel from the front of the = keyframe towards the back, as the back want to raise because the frame is not = stiff enough.</SPAN></DIV> <DIV><SPAN class=804302620-26052003><FONT face=Arial color=#0000ff = size=2></FONT></SPAN> </DIV> <DIV><SPAN class=804302620-26052003><FONT face=Arial color=#0000ff = size=2>Seem also that the hammer have less benefit of the mass of the whippen, while = if saturating we feel the action as being more driven towards the hammer = (if you see what I mean !)</FONT></SPAN></DIV> <DIV><SPAN class=804302620-26052003><FONT face=Arial color=#0000ff = size=2></FONT></SPAN> </DIV> <DIV><SPAN class=804302620-26052003><FONT face=Arial color=#0000ff = size=2></FONT></SPAN> </DIV> <DIV><SPAN class=804302620-26052003><FONT face=Arial color=#0000ff = size=2>On hardwood keyframe this is not a problem, and heavy bedding is not = feasible, the action would give a very knoky tone then.</FONT></SPAN></DIV> <DIV><SPAN class=804302620-26052003><FONT face=Arial color=#0000ff = size=2></FONT></SPAN> </DIV> <DIV><SPAN class=804302620-26052003><FONT face=Arial color=#0000ff = size=2>But still there is a small zone where the change in bedding is changing the = tone from mellow to more straight.</FONT></SPAN></DIV> <DIV><SPAN class=804302620-26052003><FONT face=Arial color=#0000ff = size=2></FONT></SPAN> </DIV> <DIV><SPAN class=804302620-26052003><FONT face=Arial color=#0000ff = size=2></FONT></SPAN> </DIV> <DIV><SPAN class=804302620-26052003><FONT face=Arial color=#0000ff = size=2>Till next time !</FONT></SPAN></DIV> <DIV><SPAN class=804302620-26052003><FONT face=Arial color=#0000ff = size=2></FONT></SPAN> </DIV> <DIV><SPAN class=804302620-26052003><FONT face=Arial color=#0000ff = size=2>Isaac</FONT></SPAN></DIV> <DIV> </DIV> <P><FONT size=2>Isaac OLEG<BR><BR>Entretien et réparation de pianos.<BR><BR>PianoTech<BR>17 rue de Choisy<BR>94400 VITRY sur SEINE<BR>FRANCE<BR>tel : 033 01 47 18 06 98<BR>fax : 033 01 47 18 06 = 90<BR>cell: 06 60 42 58 77 </FONT></P> <BLOCKQUOTE dir=ltr style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: #0000ff 2px = solid; MARGIN-RIGHT: 0px"> <DIV class=OutlookMessageHeader dir=ltr align=left><FONT = face=Tahoma size=2>-----Message d'origine-----<BR><B>De :</B> pianotech-bounces@ptg.org [mailto:pianotech-bounces@ptg.org]<B>De la = part de</B> Richard Brekne<BR><B>Envoyé :</B> lundi 26 mai 2003 = 21:36<BR><B>À :</B> Pianotech<BR><B>Objet :</B> Re: = No Power Yamaha revisited<BR><BR></FONT></DIV>  <P>A440A@aol.com wrote: <BLOCKQUOTE TYPE="CITE">Bill writes: <BR>>I agree that a good = healthy blow will put the frame under pressure, <BR>>but if the BR = doesn't have anywhere to go (because the glides are <BR>>contacting the bed), <P>  I have been wondering when somebody is going to mention = the entrainment of <BR>the keybed?  Once the glides are in contact, = the action cannot move, UNLESS <BR>the keybed is not absolutely rigid.</P></BLOCKQUOTE>Hmmm... I wonder about this. I know it makes = sense.... and indeed that very assumption has been the basis of how I've = approached bedding the keyframe for years. Yet the last few days has demonstrated = that putting the key frame under stress by turning the bolts down a bit = more, significantly afftect the power of the action and quite clearly = decreases the amount of movement in neighboring hammers and shanks at fff levels of play.  If it was the keybed I suppose I would expect any = instability to be most apparent in the center of the keyboard, but I dont. Its always = the bass and tenor regions that have given me most trouble... especially = the bass. <BR><BR>I guess that the added stress of the bolts being turned down a = bit just makes the whole frame a bit stiffer, perhaps causeing the back = rail to strain up against the dags contributes to this ??. But I dont really = see how the increased stress beyond solid contact by the glide bolts is doing = what it seems to be doing. <BR>  <BLOCKQUOTE TYPE="CITE"> But we know the keybed isn't.  = This is <BR>easily seen by depressing the pedals under a very lightly bedded = set of glides and <BR>observing them to lose contact with the keybed. <BR>   So,  the extra power and tone being ascribed = to heavier loading on the <BR>glide buttons may possibly be a function = of preload on the keybed?</BLOCKQUOTE> <P><BR>Hmmm... maybe...at least in part. <BLOCKQUOTE TYPE="CITE">And the <BR>observed differences between = makes of pianos may be more due to the differences <BR>between keybed = strength than the flexibility of the balance rails?? <BR>Wondering, <BR>Ed Foote = RPT <BR><A = href="https://www.moypiano.com/resources/#archives"></A> </BLOCKQ= UOTE>FWIW, I did the other Yamaha today... a C7, and one of our students came = into get ready for a performance and sat down to play whereby she immediatly = smiled up to me and said "AH.... there's some springyness to the piano now... = what did you do ?"... I asked her if she was certain it wasnt too much and she = played a bit and said it was just perfect. <P>Rougly, they were a 3rd of a turn backed off from loosening the = front rails grip on a thin strip of paper and evened. <P>All this is a bit new to me, so I'm having great fun reading Bills, = Rogers, and others thoughts on the matter. <P>Clearly theres more to it then just gettting the glidebolts to all = contact the keybed. <P>Cheers <BR>RicB <P>-- <BR>Richard Brekne <BR>RPT, N.P.T.F. <BR>UiB, Bergen, Norway = <BR><A href="mailto:rbrekne@broadpark.no">mailto:rbrekne@broadpark.no</A> = <BR><A = href="http://home.broadpark.no/~rbrekne/ricmain.html">http://home.broad= park.no/~rbrekne/ricmain.html</A> <BR><A = href="http://www.hf.uib.no/grieg/personer/cv_RB.html">http://www.hf.uib= .no/grieg/personer/cv_RB.html</A> <BR>  </P></BLOCKQUOTE></BODY></HTML>