Yes, that's what I've experienced -- sharp when cold, flat when warm. I worked at a piano store where the grand in the south-facing show window, with its lid up, received the full effect of all-afternoon sun, and would drop in pitch dramatically, even if recently tuned. <br> Not thinking ahead, and wiith the action in the piano, I've used a heat gun in uprights to warm shanks for correcting the hammer angle. If too many are done in the same area, the strings heat up and go flat. <br> I've read that pipe organs, and brass wind instruments (I don't know about the woodwinds) do the opposite -- flat when cold, sharp when warm. <br> --David Nereson, RPT<br><br><div class="gmail_quote">On Sun, Feb 24, 2013 at 9:16 PM, <span dir="ltr"><<a href="mailto:Jlmatt@aol.com" target="_blank">Jlmatt@aol.com</a>></span> wrote:<br> <blockquote class="gmail_quote" style="margin:0 0 0 .8ex;border-left:1px #ccc solid;padding-left:1ex"><u></u> <div style="font-size:10pt;font-family:Arial"><font color="#000000" face="Arial"> <div>No Wim and Marshall, it's the opposite! Read what you wrote before you click "send"! </div> <div> </div> <div>Jean-Luc</div> <div> </div> <div> <div>In a message dated 2/24/2013 6:47:43 P.M. Mountain Standard Time, <a href="mailto:tnrwim@aol.com" target="_blank">tnrwim@aol.com</a> writes:</div> <blockquote style="BORDER-LEFT:blue 2px solid;PADDING-LEFT:5px;MARGIN-LEFT:5px"><font style="BACKGROUND-COLOR:transparent" color="#000000" face="Arial"><font color="black" face="Arial, Helvetica, sans-serif"> <div><font style="BACKGROUND-COLOR:transparent" face="Arial, Helvetica, sans-serif">Yes, Marshall, the pitch of a piano does go sharp when the temperature rises, or goes flat when the temperature drops. You understand, of course, only if the temperature in the room in which the piano is goes up or down. The pitch also goes up or down depending on the humidity level in the room. </font></div> <div> </div> <div>Isn't this something sort of basic that your learned in school? So why do you ask?</div> <div> </div> <div>Wim</div> <div></div> <div style="CLEAR:both"> <div> </div></div> <div></div> <div></div> <div style="font-size:10pt;font-family:arial,helvetica">-----Original Message-----<br>From: Marshall Gisondi <<a href="mailto:pianotune05@hotmail.com" target="_blank">pianotune05@hotmail.com</a>><br>To: pianotech <<a href="mailto:pianotech@ptg.org" target="_blank">pianotech@ptg.org</a>><br>Sent: Sun, Feb 24, 2013 3:28 pm<br>Subject: [pianotech] pitch of a piano<br><br> <div> <div dir="ltr"><font face="Arial" size="3">Hi Everyone,</font><br><font face="Arial" size="3">I thought the pitch of a piano rises when the temp rises or goes sharp and when it's cold goes flat? </font><br><font face="Arial" size="3">Marshall<br></font><br><br><i><font face="Arial" size="3">Marshall Gisondi</font></i><br><i><font face="Arial" size="3">MARSHALL'S PIANO SERVICE</font></i><br> <i><font face="Arial" size="3">215-510-9400</font></i><br><i><font face="Arial" size="3"><a title="http://www.phillytuner.com/" href="http://www.phillytuner.com/" target="_blank">http://www.phillytuner.com</a> </font></i><br><br></div></div></div></font></font></blockquote></div></font></div></blockquote></div><br>