<!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 6.00.2900.2802" name=GENERATOR></HEAD> <BODY id=role_body style="FONT-SIZE: 10pt; COLOR: #000000; FONT-FAMILY: = Arial" bottomMargin=7 leftMargin=7 topMargin=7 rightMargin=7><FONT id=rol= e_document face=Arial color=#000000 size=2> <DIV> <DIV>  <FONT size=3>Mike /Ron</FONT></DIV> <DIV><FONT size=3>   Mike, Thanks  for the kind comments of= appreciation.</FONT></DIV> <DIV><FONT size=3>  Mike this stiffness question is surely relev= ant to us all. How stiff is too stiff?</FONT></DIV> <DIV><FONT size=3>  I've maintained that a too stiff system yields a sustain that must be extricated by stiffer & stiffer hammers until it's = not retrievable. ie too much bearing on an otherwise well supported belly chokes the sound</FONT></DIV> <DIV><FONT size=3>     I agree with Ron, usually a saf= e thing to do, grin,<STRONG> and it's also true in this  case t= he extra ribs are primarily for crown support & turning them perpendicular = to the bridge & obtuse to the grain angle of the sound board increases stiffness without adding mass</STRONG>.  Del's/Rons have been sayi= ng this for years now & I finally proved it to myself.</FONT></DIV> <DIV><FONT size=3>     The upper part of the treble bo= ard in the last octave & half area is quite stiff simply because the board spans an ever decreasing span between belly rail and curve side o= f case. Combine this with a stiff bridge on top in the same vicinity ands= some short spruce ribs and this is going to drive the tone.  = Of course adequate down bearing assumned.  </FONT></DIV> <DIV><FONT size=3>    Sincerely</FONT></DIV> <DIV><FONT size=3>  Dale Erwin</FONT></DIV> <DIV> </DIV> <BLOCKQUOTE style="PADDING-LEFT: 5px; MARGIN-LEFT: 5px; BORDER-LEFT: blue 2px solid"><= FONT style="BACKGROUND-COLOR: transparent" face=Arial color=#000000 size= =2>> Primarily for Dale Erwin, (who was generous enough to share his thoughts<BR>> and his photos with us all through the PTG Journal) but anyone please feel<BR>> free to chime in if you've got thoughts on this...<BR>> <BR>> Most rib scale modifications I've seen / heard ab= out involve additional<BR>> ribs, closer together, and perpendicular to the= bridge, in the treble. <BR>> Reasons:  maintain crown, increase impedence for longer sustain.  I'm<BR>> wondering how critical it = is to get enough but not too much increased<BR>> stiffness.  Have you= ever gone too far?  What were the resulting symptoms?<BR>> <BR>&gt= ; thanks<BR>> <BR>> Mike<BR><BR>The addition of treble ribs is realistically more important to crown <BR>support in the killer octave tha= n to high treble stiffness. The <BR>symptom of too much stiffness in the high e= nd is that short sustain <BR>screaming treble we talked about a couple of wee= ks ago. The cure is <BR>mass to get the fundamental resonant frequency down.<BR><BR>Ron N<BR>_______________________________________________</FONT></BLOCKQUOTE></DI= V> <DIV></DIV> <DIV> </DIV> <DIV> </DIV> <DIV><FONT lang=0 face=Arial size=2 FAMILY="SANSSERIF" PTSIZE="10"= ><B>Dale Erwins Piano Restorations</B> <BR>4721 Parker Rd.<BR>Modesto, Ca 95357<BR>209-577-8397 cell 209-985-0990<BR><B><U>Featuring Custom Restoratio= n Services<BR>& Sales Of Restored </B></U><BR><B><U>Steinway ,and Mason &a= mp; Hamlin Pianos</B></U><BR>www.Erwinspiano.com</FONT></DIV></FONT></BODY></HTM= L>