<head><style>body{font-family: Geneva,Arial,Helvetica,sans-serif;font-size:9pt;background-color: #ffffff;color: black;}</style><style></style></head><body id="compText">This kind of procedure could be turned into a spreadsheet, or a database, pretty easy. Plug certain parameters into a form and let the computer do the math... Has no one done this kind of thing already...?<br><br>Matt<br><blockquote style="border-left: 2px solid rgb(0, 0, 255); padding-left: 5px; margin-left: 0px;">-----Original Message-----
<br>From: A440 Piano Service <a440@bresnan.net>
<br>Sent: Feb 4, 2008 9:00 PM
<br>To: PTG List <pianotech@ptg.org>
<br>Subject: Regulating Without Specs
<br><br>
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</zzzbody></zzzmeta></zzzhead></zzzhtml></pianotech@ptg.org></a440@bresnan.net><div><font face="Arial" size="2">Hello List,</font></div>
<div><font face="Arial" size="2"></font> </div>
<div><font face="Arial" size="2">I'm writing an article about regulating pianos when
you don't have specifications. I'll paste in the simple nuts and bolts of
it below. I'd appreciate your feedback. I know there are some setup
caveats and pitfalls, and some other considerations, but rather than lay all of
them out, I thought I'd wait and hear from you guys about what you see as strong
points, weak points, yeah buts, and any other considerations.</font></div>
<div><font face="Arial" size="2"></font> </div>
<div><font face="Arial" size="2">Anyway, here's a simple rough draft:</font></div>
<div><font face="Arial" size="2"></font> </div>
<div>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">No Regulation Specs?<span style=""> </span>Regulate by action ratio analysis!</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">What if you had no regulation
specs, or the specs you had were not working out.<span style=""> </span>Wouldnt it be great if there was a way
that you could come up with workable specs in minutes?<span style=""> </span>Specs that you could custom design
depending on your performance priorities?</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">I got to thinking that if you
knew what the action ratio was on a piano, you could just do the math and come
up with a workable set of specs to regulate it with.<span style=""> </span>By making algebraic equations of the
variables, you could even customize a regulation based on what your priorities
were, be it key dip or blow distance.</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">Heres how it works:<span style=""> </span>First you determine what the action
ratio is by measuring how much the hammer moves compared to how much the key
moves.<span style=""> </span>(Mechanical Action Ratio, or
MAR) Youll need to move the key LESS than letoff and eliminate lost motion
first, so you can directly measure the hammer movement that results from key
movement.<span style=""> </span>Now say you move the key
down ¼ and the hammer moves 1 ¼.<span style="">
</span>You divide the hammer movement by the key movement and discover an action
ratio of 5:1.<span style=""> </span>With this number, you
can now determine regulation specs for blow distance, key dip, letoff and
aftertouch.</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">Lets just say you want something
typical like a 3/8 key dip, 1/8 letoff, and .050 aftertouch.<span style=""> </span>(Later Ill show the equations for
solving for different variables)<span style="">
</span>Given the 3/8 key dip (.375) and the .050 aftertouch, we subtract
aftertouch from key dip and know then that we have .325 of useable key dip to
move the hammer.<span style=""> </span>How far will it
move?<span style=""> </span>It will move 5xs the amount
of keydip.<span style=""> </span>5 x .325 = 1.625.<span style=""> </span>But thats not the hammer blow distance,
because we havent accounted for letoff.<span style="">
</span>If we want 1/8 (.125) letoff, we need to ADD that to the hammer travel
of 1.625, so the blow distance is then 1.75, or 1 ¾.</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">OK, lets make that work out
algebraicly. </p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">Key travel<span style=""> </span>= Kt</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">Hammer travel = Ht</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">Action Ratio = Ar</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">Blow Distance = Bd</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">Key Dip = Kd</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">Aftertouch = At</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">Letoff = Lo</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">Equation 1:<span style=""> </span>Determine Action Ratio</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style="">
</span>Ht/Kt = Ar</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">Equation 2: Determine Blow
Distance<span style=""> </span>(you pick key dip,
aftertouch and letoff specs, as in the above example)</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style="">
</span>Bd = [(Kd At) x Ar] + Lo</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;">Equation 3:<span style=""> </span>Determine Key Dip<span style=""> </span>(you pick blow distance, aftertouch, and
letoff)</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style="">
</span>Step one: determine Hammer Travel<span style="">
</span></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt 0.5in; text-indent: 0.5in;">Bd Lo
= Ht</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style="">
</span>Step two: determine Key Travel for that hammer travel</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt 0.5in; text-indent: 0.5in;">Ht/Ar =
Kt</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style="">
</span>Step three: add desired aftertouch to Key Travel to get Key Dip.</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style="">
</span><span style="">
</span>Kt + At = Kd</p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style="">
</span></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style=""></span> </p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style=""><font face="Arial" size="2"></font></span> </p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style=""><font face="Arial" size="2">OK, Lemme know whatcha
think!</font></span></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style=""><font face="Arial" size="2"></font></span> </p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style=""><font face="Arial" size="2">John Dorr, RPT (<---
brand NEW RPT, but I love writing this!)</font></span></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"><span style=""><font face="Arial" size="2">Helena, MT</font></span></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p>
<p class="MsoNormal" style="margin: 0in 0in 0pt;"> <o:p></o:p></p></div>
<div><font face="Arial" size="2"></font> </div>
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