<HTML><HEAD> <META name=GENERATOR content="MSHTML 8.00.6001.19298"></HEAD> <BODY> <DIV> <DIV><FONT size=2 face="MS Sans Serif">Nick,</FONT></DIV> <DIV><FONT size=2 face="MS Sans Serif">Yes, I do get it. Was just not up on the current "buzz words"!<G> I don't agree with some of the major ASSUMPTIONS in your explanation, but I'll go along anyway.<G> Hope all's well in your world, Much thanks for the enlightenment.<G></FONT></DIV> <DIV><FONT size=2 face="MS Sans Serif">Best,</FONT></DIV> <DIV><FONT size=2 face="MS Sans Serif">Joe</FONT></DIV> <DIV> </DIV> <DIV></DIV></DIV> <DIV> </DIV> <BLOCKQUOTE style="BORDER-LEFT: #000000 2px solid; PADDING-LEFT: 5px; PADDING-RIGHT: 0px; MARGIN-LEFT: 5px"> <DIV style="FONT: 10pt Arial">----- Original Message ----- </DIV> <DIV style="FONT: 10pt arial; BACKGROUND: #e4e4e4; font-color: black"><B>From:</B> <A title=ngravagne@gmail.com href="mailto:ngravagne@gmail.com">Nicholas Gravagne</A> </DIV> <DIV style="FONT: 10pt arial"><B>To: </B><A title=joegarrett@earthlink.net href="mailto:joegarrett@earthlink.net">joegarrett@earthlink.net</A>;<A title=pianotech@ptg.org href="mailto:pianotech@ptg.org">pianotech@ptg.org</A></DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> 8/25/2012 10:48:56 AM </DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [pianotech] action ratio</DIV> <DIV><BR></DIV><FONT size=2>Joe,<BR><BR>You actually DO know this. "Key in", etc. is that portion of an action component  that represents the effort or activation arm of the lever in question. The "outs" are the resistance arms. So in broad terms, "key in" is the front half of the key and the key out is the back "half" from balance to capstan. Ditto on the whip and shanks. Multiplying the ratios of the key, whip and shank (each component having its own effort and resistance arms), as they exist on the left hand side of the equation yields the action ratio (AR), also referred to as the transmission ratio by Pfieffer in his books. <BR><BR>I don't know if it shows up in all email clients, but the entire equation as posted, both left and right hand sides should be shown as as division, which is to say these also represent ratios. Given that, then the left side ratio (even though it derives as a product of three ratios) is equivalent to the right side ratio (even though the right side indicates --- or should depending on how you see in in the post --- as blow-distance-minus-let-off (divided by) key-dip-minus-aftertouch). <BR><BR>Since there are so many variables here, there can be no one standard for aftertouch. So without running a bunch of example numbers right now, let's say we multiply the three component ratios and the AR works out as 5.8 to 1. Another action might yield 5.58 and so on. However, blow distances and let-offs do not generally vary much, so these can almost be stated as fixed constants (say 46mm blow and 2mm let off). Key dips can vary more so, but again, about 10mm plus or minus. <BR><BR>Thus, given the equation it is clear that the left side must equal the right side, say 5.8 on the left side must somehow equal 5.8 on the right. If blow distance is locked in at 46 and let off at 2, then this equals (46 - 2) or 44 . Now if key dip is locked in at 10, then all that is left unknown is after touch. Some simple algebra yields the unknown after touch as 2.41mm (0.095"). The formula will now balance since:<BR><BR>(Let side Action ratio) of 5.8 is to1 as the: <BR>(Right side Regulation Parameters) of (46 - 2) to (10 - 2.41) or 44 to 7.58. Thus the right hand and left hand ratios are satisfied at 5.8<BR><BR>Now having said this, note two things at least:<BR><BR>1) given the action ratio (AR) as fixed, which it is, once established one way or another, the only "fudge-ables" are action regulation parameters. But regardless of what you do with the regulations, these will always balance the AR value.<BR><BR>2) the reason there can be no one aftertouch value to fit all situations is that the ARs from one action to another are not all the same; and so "as goes the AR, so goes the regulation" (which includes the aftertouch portion).<BR><BR>And so, Joe, you old curmudgeon and Captain of the Tool Police, I really DO think you get this <G><BR><BR>NG <BR><BR><FONT size=+0><FONT color=navy face="Comic Sans MS, sans-serif"><PRE style="FONT-SIZE: 9pt"><TT>Key out x wippen out x shank out = blow distance - let off Key in wippen in shank in key dip - after touch</TT></PRE></FONT></FONT><BR><BR> <DIV class=gmail_quote>On Sat, Aug 25, 2012 at 8:34 AM, Joseph Garrett <SPAN dir=ltr><<A href="mailto:joegarrett@earthlink.net" target=_blank>joegarrett@earthlink.net</A>></SPAN> wrote:<BR> <BLOCKQUOTE style="BORDER-LEFT: #ccc 1px solid; MARGIN: 0px 0px 0px 0.8ex; PADDING-LEFT: 1ex" class=gmail_quote> <DIV> <DIV> <DIV><FONT face="MS Sans Serif">And they mean what?! I'll need something a bit stronger, like a good single malt!"Key in"??? What does that refer to? Just because some brainiac thunk that up, doesn' mean squat unless an explanation is with it imo.<G></FONT></DIV> <DIV><FONT face="MS Sans Serif">Joe</FONT></DIV> <DIV> </DIV> <DIV></DIV></DIV> <DIV> <DIV class=h5> <DIV> </DIV> <BLOCKQUOTE style="BORDER-LEFT: #000000 2px solid; PADDING-LEFT: 5px; PADDING-RIGHT: 0px; MARGIN-LEFT: 5px"> <DIV style="FONT: 10pt Arial">----- Original Message ----- </DIV> <DIV style="FONT: 10pt arial; BACKGROUND: #e4e4e4"><B>From:</B> <A title=erwinspiano@aol.com href="mailto:erwinspiano@aol.com" target=_blank>Dale Erwin</A> </DIV> <DIV style="FONT: 10pt arial"><B>To: </B><A title=joegarrett@earthlink.net href="mailto:joegarrett@earthlink.net" target=_blank>joegarrett@earthlink.net</A>;<A title=pianotech@ptg.org href="mailto:pianotech@ptg.org" target=_blank>pianotech@ptg.org</A></DIV> <DIV style="FONT: 10pt arial"><B>Sent:</B> 8/25/2012 8:18:25 AM </DIV> <DIV style="FONT: 10pt arial"><B>Subject:</B> Re: [pianotech] action ratio</DIV> <DIV><BR></DIV><FONT size=+0><FONT color=navy face="Comic Sans MS, sans-serif"><FONT color=#000080 size=3 face="Comic Sans MS, sans-serif">These are formulas used by Nick Gravagne , David Stanwood and others to determine the overall action ratio. Which is a very useful thing to know.</FONT> <DIV><FONT size=3><FONT color=#000080 face="Comic Sans MS, sans-serif"> </FONT><FONT color=#000080 face="Comic Sans MS, sans-serif">Need</FONT><FONT color=#000080 face="Comic Sans MS, sans-serif"> some Excedrin now Joe?</FONT></FONT><BR><BR> <DIV style="FONT-FAMILY: 'Comic Sans MS',sans-serif; COLOR: navy; CLEAR: both; FONT-SIZE: 10pt"><FONT color=royalblue size=1><B><FONT face="Georgia, Times New Roman, Times, Serif"><FONT color=black><FONT color=mediumblue face="Comic Sans MS, sans-serif">Dale Erwin R.P.T.<BR><FONT color=green>Erwin's Piano Restoration Inc.</FONT><BR></FONT></FONT></FONT></B></FONT><FONT color=darkgreen><SPAN style="FONT-STYLE: italic"><B><FONT size=1><FONT color=black size=1><FONT color=blueviolet><FONT color=black><FONT color=black face="Comic Sans MS, sans-serif">Mason & Hamlin</FONT><FONT face="Comic Sans MS, sans-serif">/Steinway/</FONT><FONT color=black face="Comic Sans MS, sans-serif">U.S. pianos</FONT><FONT face="Comic Sans MS, sans-serif"><BR></FONT></FONT></FONT></FONT><FONT color=cornflowerblue size=1 face="Comic Sans MS, sans-serif"><A href="http://www.Erwinspiano.com" target=_blank>www.Erwinspiano.com</A></FONT><FONT size=1><BR></FONT><FONT color=crimson size=1 face="Comic Sans MS, sans-serif">Phone: <A href="tel:209-577-8397" target=_blank value="+12095778397">209-577-8397</A></FONT><BR><FONT size=+0></FONT></FONT></B></SPAN></FONT><TT><TT><FONT color=darkgreen><BR> </FONT><BR>  <FONT size=+0></FONT></TT></TT><BR><BR></DIV><BR><BR> <DIV style="FONT-FAMILY: arial,helvetica; FONT-SIZE: 10pt">-----Original Message-----<BR>From: Joseph Garrett <<A href="mailto:joegarrett@earthlink.net" target=_blank>joegarrett@earthlink.net</A>><BR>To: pianotech <<A href="mailto:pianotech@ptg.org" target=_blank>pianotech@ptg.org</A>><BR>Sent: Sat, Aug 25, 2012 8:03 am<BR>Subject: Re: [pianotech] action ratio<BR><BR> <DIV style="MARGIN: 0px; FONT-FAMILY: Tahoma,Verdana,Arial,Sans-Serif; FONT-SIZE: 12px"><PRE style="FONT-SIZE: 9pt"><TT>David said: "One formula for the action ratio has been given as: Key out x wippen out x shank out = blow distance - let off Key in wippen in shank in key dip - after touch Does anyone happen to know what the standard (or minimum) aftertouch is in this formula or how it was derived? " David, First of all, I need to know what the hell "key out...." and "key in..." means. Have never heard the terms. I suspect if I knew, I'd get a headache Joe Joe Garrett, R.P.T. Captain of the Tool Police Squares R I </TT></PRE></DIV></DIV></DIV></FONT></FONT></BLOCKQUOTE></DIV></DIV></DIV></BLOCKQUOTE></DIV><BR><BR clear=all><BR>-- <BR>Nick Gravagne, RPT<BR>AST Mechanical Engineering<BR></FONT></BLOCKQUOTE></BODY></HTML>