<html> <head> <style></style> </head> <body class='hmmessage'><div dir='ltr'> Here is a cutout of an interview with Stefan Knüpfer about that question:<br><br><h3><b>Bitte erklären Sie: Wie kommt ein Klavierstimmer auf die Idee, mit einem Tennisball im Flügel herumzuhantieren?</b></h3>Das Problem war Folgendes: Wir hatten ein Instrument, das lange nicht gespielt wurde. Das hatte sich festgestanden, klang nicht mehr. Wenn man da plötzlich einen Pianisten drauf spielen lässt, ist der Abrieb groß, und es verschließt sich. Das ist wie ein Oldtimer, der nie gefahren wird, und dann lässt man einen Rennfahrer damit auf die Autobahn fahren. Der zerfährt Ihnen das Auto komplett. Also dachte ich, okay, wir bewegen den Resonanzboden nicht über die Mechanik, sondern geben Impulse von oben. Und so kam ich darauf, einen Tennisball mithilfe einer Stichsäge auf- und abzubewegen, damit klopft man den Flügel schön weich, der bekommt einen unglaublich freien Ton davon. Die Frage ist immer: Was ist physikalisch das Problem, und wie kann ich es physikalisch lösen? Da ist mir jedes Mittel recht.<BR><br><BR><b>Basicaly it says this in English:</b><BR><br><BR>Why to use a tennis ball in a grand?<BR>Long time no play, piano is like sticked in the mud, it needs energy to move and swing free again. The idea is to put energy into the soundboard not via the action but from above with the aid of a tennisball of a jig saw. It knocks the piano beautyful soft and it gets a free tone.<br><BR><br><BR>Here is the link to the complete interview (in German):<BR><br><BR>http://www.faz.net/artikel/C30964/das-wohltemperierte-klavier-stimmt-so-30305528.html<BR><br><BR>Gregor<br><BR><br><BR><br><br>------------------------<br>piano technician - tuner - dealer<br>Münster, Germany<br>www.weldert.de<br><br><br><div><hr id="stopSpelling">Date: Thu, 29 Sep 2011 22:35:08 -0700<br>From: tunerryan@gmail.com<br>To: pianotech@ptg.org<br>Subject: Re: [pianotech] FW: what is this?<br><br>The idea must be to seat the strings, similar to what many of us do with a brass rod. I'm not sure what the advantage would be, but it would sure impress some clients! <br><br>Ryan<br><br><div class="ecxgmail_quote">On Thu, Sep 29, 2011 at 9:37 PM, <span dir="ltr"><<a href="mailto:tnrwim@aol.com">tnrwim@aol.com</a>></span> wrote:<br> <blockquote class="ecxgmail_quote" style="border-left:1px #ccc solid;padding-left:1ex"><font size="2" color="black" face="arial"> <div>It looks like a tennis ball hooked up to an electric jig saw, which sits on a platform over the strings. I guess to pound in the strings? </div> <div> </div> <div>Wim<br> </div><div><div></div><div class="h5"> <div style="font-family:arial,helvetica;color:black;font-size:10pt"> <blockquote style="border-left:blue 2px solid;padding-left:3px"><font size="2" color="black" face="Arial"><span style="font-family:Arial;color:black;font-size:10pt"></span></font></blockquote></div> <br> <br> <br> <div style="font-family:arial,helvetica;color:black;font-size:10pt">-----Original Message-----<br> From: Jack Houweling <<a href="mailto:jackhouweling@dccnet.com">jackhouweling@dccnet.com</a>><br> To: pianotech <<a href="mailto:pianotech@ptg.org">pianotech@ptg.org</a>><br> Sent: Thu, Sep 29, 2011 6:18 pm<br> Subject: [pianotech] FW: what is this?<br> <br> <div> <div> <div class="ecxMsoNormal"><font size="2" color="black" face="Arial"><span style="font-family:Arial;color:black;font-size:10pt"> </span></font></div> <div class="ecxMsoNormal"><font size="2" color="navy" face="Arial"><span style="font-family:Arial;color:navy;font-size:10pt"> </span></font></div> <div class="ecxMsoNormal"><font size="2" color="navy" face="Arial"><span style="font-family:Arial;color:navy;font-size:10pt"> </span></font></div> <div> <div style="text-align:center" class="ecxMsoNormal" align="center"><font size="3" face="Times New Roman"><span style="font-size:12pt"> <hr size="2" width="100%" align="center"> </span></font></div> </div> <div class="ecxMsoNormal"><font size="3" face="Times New Roman"><span style="font-size:12pt"> </span></font></div> <div class="ecxMsoNormal"><font size="3" face="Times New Roman"><span style="font-size:12pt">I saw this video on You Tube called Pianomania, it has a Steinway concert technician</span></font></div> <div class="ecxMsoNormal"><font size="3" face="Times New Roman"><span style="font-size:12pt">named Stefan Knupfer working for Lang Lang, and at 0:47 he shows some kind of pounder. Does anyone know what it</span></font></div> <div class="ecxMsoNormal"><font size="3" face="Times New Roman"><span style="font-size:12pt">is or what it does?  Check out video link below.</span></font></div> <div class="ecxMsoNormal"><font size="3" face="Times New Roman"><span style="font-size:12pt"> </span></font></div> <div class="ecxMsoNormal"><font size="3" face="Times New Roman"><span style="font-size:12pt">Jack Houweling</span></font></div> <div class="ecxMsoNormal"><font size="3" face="Times New Roman"><span style="font-size:12pt"> </span></font></div> <div class="ecxMsoNormal"><font size="3" face="Times New Roman"><span style="font-size:12pt"> </span></font></div> <div class="ecxMsoNormal"><font size="3" face="Times New Roman"><span style="font-size:12pt"> </span></font></div> <div class="ecxMsoNormal"><font size="3" face="Times New Roman"><span style="font-size:12pt"><a href="http://www.youtube.com/watch?v=HWhRZmaFwLU&feature=BFa&list=PLEE6173BD97999F94&lf=results_video" target="_blank">http://www.youtube.com/watch?v=HWhRZmaFwLU&feature=BFa&list=PLEE6173BD97999F94&lf=results_video</a></span></font><font size="2" face="Arial"><span style="font-family:Arial;font-size:10pt"></span></font></div> </div> </div> </div> </div></div></font></blockquote></div><br><br clear="all"><br>-- <br>Ryan Sowers, RPT<br>Puget Sound Chapter<br>Olympia, WA<br><a href="http://www.pianova.net" target="_blank">www.pianova.net</a><br></div> </div></body> </html>