<!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 4.0 Transitional//EN"> <HTML><HEAD> <META http-equiv=Content-Type content="text/html; = charset=iso-8859-1"> <META content="MSHTML 6.00.2800.1264" name=GENERATOR> <STYLE></STYLE> </HEAD> <BODY> <DIV><FONT size=2></FONT><FONT face=Arial>I don't think anyone is = questioning the effects of RH changes on the tuning of a piano.</FONT></DIV> <DIV><FONT face=Arial></FONT> </DIV> <DIV><FONT face=Arial>I'm with Sarah and feel that proper full = environment humidity control is the best way to go - better than a full DC installation.</FONT></DIV> <DIV><FONT face=Arial></FONT> </DIV> <DIV><FONT face=Arial>I think where the arguement comes in is the fact = that probably 99% of full environment humidity control systems are improperly = designed, poorly functioning, turned off and windows opened up, turned = off over the holidays and summer, etc., etc. <DIV><FONT face=Arial></FONT> </DIV> <DIV><FONT face=Arial>But this does not change the fact that if one = installs a proper full environment humidity control system that holds the RH = constant within a few percent, it will be more effective than a full DC.</FONT></DIV></FONT></DIV> <DIV><FONT face=Arial></FONT> </DIV> <DIV><FONT face=Arial>And don't forget that even if you hard-wire the = DC system into the wall, who is ever going to notice that the circuit breaker = tripped 15 months ago and the piano hasn't had any humidity control since that time?</FONT></DIV> <DIV><FONT face=Arial></FONT><FONT face=Arial></FONT> </DIV> <DIV><FONT face=Arial>In my shop I have a Sears basement-type = dehumidifier. It keeps the shop right at 45% RH (within a percent or two). I never = varies. How in the world is a DC unit on a piano in my shop going to work better, or do = anything at all besides vapor, dry, vapor, dry, vapor, dry, etc., etc.?</FONT></DIV> <DIV><FONT face=Arial></FONT> </DIV> <DIV><FONT face=Arial>So I guess the bottom line is that if one is = willing to set up a proper full environment humidity control system that holds the = RH constant within a few percent, that is the best way to go. From a = practical standpoint, knowing that 90-some% of full environment humidity = control systems are not going to be real effective, the full DC-type system is = the way to go (they DO work quite well). And as someone pointed out, from a = practical standpoint a full DC-type system in a piano which is in an environment = modified by a full environment humidity control systems is the best around. </FONT></DIV> <DIV><FONT face=Arial></FONT> </DIV> <DIV><FONT face=Arial>Flame Suite Tighly Zipped,</FONT></DIV> <DIV><FONT face=Arial></FONT> </DIV> <DIV><FONT face=Arial>Terry Farrell</FONT></DIV> <DIV><FONT face=Arial size=2></FONT> </DIV> <DIV><FONT face=Arial size=2>----- Original Message ----- </FONT> <DIV><FONT face=Arial size=2>From: "DIANE HOFSTETTER" <</FONT><A href="mailto:dianepianotuner@msn.com"><FONT face=Arial size=2>dianepianotuner@msn.com</FONT></A><FONT face=Arial size=2>></FONT></DIV> <DIV><FONT face=Arial size=2>To: <</FONT><A href="mailto:pianotech@ptg.org"><FONT face=Arial size=2>pianotech@ptg.org</FONT></A><FONT face=Arial = size=2>></FONT></DIV> <DIV><FONT face=Arial size=2>Sent: Tuesday, January 13, 2004 2:51 AM</FONT></DIV> <DIV><FONT face=Arial size=2>Subject: Re: Where did the RH = Go</FONT></DIV></DIV> <DIV><FONT face=Arial><BR><FONT size=2></FONT></FONT></DIV><FONT = face=Arial size=2>> Sarah,<BR>> <BR>> For fourteen years now my partner = and I have been measuring and graphing the <BR>> tuning on every piano = immediately before we tune it.   We also record the <BR>> relative = humidity and temperature most of the time, whether it has a <BR>> Damppchaser = installation or not, and if it is functioning correctly.<BR>> <BR>> Then when = we next tune the piano and record all the data again, we have a <BR>> way of understanding how to service the piano to make the tuning as stable = <BR>> as possible.<BR>> <BR>> Over the years I have had fun with a variety = of experiments.  One day I <BR>> arrived to tune a piano in a room = that is routinely kept unheated with no <BR>> climate control in the = piano.  The maintenance people had just turned on the <BR>> heat before I arrived = and a stream of warm area was shooting out of the <BR>> register about ten = feet away.<BR>> <BR>> I was dismayed; the heat should have been turned = on hours before.  I knew <BR>> the tuning could not be reliable.  I = went ahead and graphed the tuning.  As <BR>> soon as I finished that = graph, I remeasured the tuning and graphed it again. <BR>>   Then I = remeasured and regraphed, and then once again.  I ended up with a <BR>> = graph showing four distinctly separate lines of the tuning as it changed = <BR>> with the relative humidity and temperature for each line carefully = recorded.<BR>> <BR>> There is no question in my mind that changes in relative = humidity affect the <BR>> tuning dramatically and that a Damppchaser system = does an excellent job of <BR>> helping control that.  I have numerous = graphs to show it does.<BR>> <BR>> Diane<BR>> <BR>> <BR>> <BR>> = <BR>> <BR>> Diane Hofstetter<BR>> <BR>> <BR>> <BR>> <BR>> = <BR>> >From: "Sarah Fox" <</FONT><A = href="mailto:sarah@gendernet.org"><FONT face=Arial size=2>sarah@gendernet.org</FONT></A><FONT face=Arial size=2>><BR>> >Reply-To: Pianotech <</FONT><A href="mailto:pianotech@ptg.org"><FONT face=Arial size=2>pianotech@ptg.org</FONT></A><FONT face=Arial = size=2>><BR>> >To: "Pianotech" <</FONT><A href="mailto:pianotech@ptg.org"><FONT = face=Arial size=2>pianotech@ptg.org</FONT></A><FONT face=Arial = size=2>><BR>> >Subject: Re: Where did the RH Go<BR>> >Date: Mon, 12 Jan 2004 = 21:48:30 -0500<BR>> ><BR>> >Hi Don,<BR>> ><BR>> > > I = did not say your system didn't work. What I said was a DC system would<BR>> = > > work even better.<BR>> ><BR>> >Perhaps.  Perhaps = not.  I don't mean to be argumentative on this point.  <BR>> = >I'm<BR>> >really asking a question here:  Have you (or has anyone else) done<BR>> >measurements with a good, accurate hygrometer on a = complete DC grand<BR>> >installation, during dry ambient conditions, showing = that humidity is <BR>> >indeed<BR>> >evenly distributed all over = the soundboard, both under and on top, and in<BR>> >the action = cavity?  Also, have the same measurements been done inside the<BR>> >piano = with a closed lid and inside the action cavity during predominantly<BR>> >dehumidifying periods?  In other words, are DC's claims fully = <BR>> >substantiated,<BR>> >as determined empirically with a hygrometer?  I've heard lots of claims<BR>> >regarding = stability of pitch.  That's all well and good, of course.<BR>> >However, = how well does the DC system regulate humidity (in contrast to<BR>> = >pitch)?<BR>> ><BR>> > > I do recommend room type humdifiers as well--but = only to "assist" a DC<BR>> > > unit. If it is a choice of one or the = other the DC provides much better<BR>> > > year round control than is = generally possible with a room type. There <BR>> >are<BR>> > > = exceptions, but they are very rare.<BR>> ><BR>> >This sounds like a = reasonable approach.<BR>> ><BR>> > > Do you have measurements for = the summer time? Where I am I have <BR>> >documented<BR>> > > as low = as 4% and as high as 84%.<BR>> ><BR>> >Without humidification, = humidity levels inside my house vary from 27% in <BR>> >the<BR>> = >winter to 67% in the late fall.  I have forced heat and refrigerated = A/C,<BR>> >BTW.  I suspect humidity levels are far different in other = parts of the<BR>> >state.  I'm in Central Ohio.  In the lake = areas, humidity is undoubtedly<BR>> >much higher during moderate = weather.  Also, I have no idea what humidity<BR>> >levels occur in other = people's homes here in Columbus.  (I don't service<BR>> >their pianos. = <grin>)<BR>> ><BR>> > > I would love to have a = controller for a DC type system that had much<BR>> > > narrower limits. I = know, for example, that rare bird hatcheries have <BR>> >units<BR>> = > > that are calibrated to 1/10 of one percent humidity that power = an<BR>> > > "electronic" fan (read no blades--some sort of vibrating plate) combined<BR>> > > with an ultrasonic humidifer. I'd love to get = my pinkies on one!<BR>> ><BR>> >Well, I can't boast 0.1% limits = with my system (WOW!!), but I do quite a <BR>> >bit<BR>> >better = than the specs DC boasts.  I did a 100% non-DC-brand installation on<BR>> = >my concert grand, using a GE humidistat that cycles the system = adjustably<BR>> >between 40 - 44% (or occasionally as widely as 39 - 45%) when the = ambient <BR>> >RH<BR>> >is in the upper 40's.  The installation = is fairly recent, so I haven't yet<BR>> >been able to observe its = behavior at higher humidity levels.  I'll give you<BR>> >an update in the = spring if you're interested.<BR>> ><BR>> >Peace,<BR>> = >Sarah<BR>> ><BR>> ><BR>> ><BR>> ><BR>> >_______________________________________________<BR>> = >pianotech list info: </FONT><A = href="https://www.moypiano.com/resources/#archives"><FONT face=Arial size=2>https://www.moypiano.com/resources/#archives</FONT></A><BR><FON= T face=Arial size=2>> <BR>> _________________________________________________________________<BR>>= Scope out the new MSN Plus Internet Software - optimizes dial-up to the max! = <BR>>    </FONT><A href="http://join.msn.com/?pgmarket=en-us&page=byoa/plus&ST= =1"><FONT face=Arial size=2>http://join.msn.com/?pgmarket=en-us&page=byoa/plus&S= T=1</FONT></A><BR><FONT face=Arial size=2>> <BR>> _______________________________________________<BR>> pianotech list = info: </FONT><A href="https://www.moypiano.com/resources/#archives"><FONT = face=Arial size=2>https://www.moypiano.com/resources/#archives</FONT></A><BR><FON= T face=Arial size=2>> </FONT></BODY></HTML>