This is a multi-part message in MIME format. ---------------------- multipart/alternative attachment I don't think anyone is questioning the effects of RH changes on the = tuning of a piano. I'm with Sarah and feel that proper full environment humidity control is = the best way to go - better than a full DC installation. 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. 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. 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? 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.? 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.=20 Flame Suite Tighly Zipped, Terry Farrell ----- Original Message -----=20 From: "DIANE HOFSTETTER" <dianepianotuner@msn.com> To: <pianotech@ptg.org> Sent: Tuesday, January 13, 2004 2:51 AM Subject: Re: Where did the RH Go > Sarah, >=20 > For fourteen years now my partner and I have been measuring and = graphing the=20 > tuning on every piano immediately before we tune it. We also record = the=20 > relative humidity and temperature most of the time, whether it has a=20 > Damppchaser installation or not, and if it is functioning correctly. >=20 > Then when we next tune the piano and record all the data again, we = have a=20 > way of understanding how to service the piano to make the tuning as = stable=20 > as possible. >=20 > Over the years I have had fun with a variety of experiments. One day = I=20 > arrived to tune a piano in a room that is routinely kept unheated with = no=20 > climate control in the piano. The maintenance people had just turned = on the=20 > heat before I arrived and a stream of warm area was shooting out of = the=20 > register about ten feet away. >=20 > I was dismayed; the heat should have been turned on hours before. I = knew=20 > the tuning could not be reliable. I went ahead and graphed the = tuning. As=20 > soon as I finished that graph, I remeasured the tuning and graphed it = again.=20 > Then I remeasured and regraphed, and then once again. I ended up = with a=20 > graph showing four distinctly separate lines of the tuning as it = changed=20 > with the relative humidity and temperature for each line carefully = recorded. >=20 > There is no question in my mind that changes in relative humidity = affect the=20 > tuning dramatically and that a Damppchaser system does an excellent = job of=20 > helping control that. I have numerous graphs to show it does. >=20 > Diane >=20 >=20 >=20 >=20 >=20 > Diane Hofstetter >=20 >=20 >=20 >=20 >=20 > >From: "Sarah Fox" <sarah@gendernet.org> > >Reply-To: Pianotech <pianotech@ptg.org> > >To: "Pianotech" <pianotech@ptg.org> > >Subject: Re: Where did the RH Go > >Date: Mon, 12 Jan 2004 21:48:30 -0500 > > > >Hi Don, > > > > > I did not say your system didn't work. What I said was a DC system = would > > > work even better. > > > >Perhaps. Perhaps not. I don't mean to be argumentative on this = point. =20 > >I'm > >really asking a question here: Have you (or has anyone else) done > >measurements with a good, accurate hygrometer on a complete DC grand > >installation, during dry ambient conditions, showing that humidity is = > >indeed > >evenly distributed all over the soundboard, both under and on top, = and in > >the action cavity? Also, have the same measurements been done inside = the > >piano with a closed lid and inside the action cavity during = predominantly > >dehumidifying periods? In other words, are DC's claims fully=20 > >substantiated, > >as determined empirically with a hygrometer? I've heard lots of = claims > >regarding stability of pitch. That's all well and good, of course. > >However, how well does the DC system regulate humidity (in contrast = to > >pitch)? > > > > > I do recommend room type humdifiers as well--but only to "assist" = a DC > > > unit. If it is a choice of one or the other the DC provides much = better > > > year round control than is generally possible with a room type. = There=20 > >are > > > exceptions, but they are very rare. > > > >This sounds like a reasonable approach. > > > > > Do you have measurements for the summer time? Where I am I have=20 > >documented > > > as low as 4% and as high as 84%. > > > >Without humidification, humidity levels inside my house vary from 27% = in=20 > >the > >winter to 67% in the late fall. I have forced heat and refrigerated = A/C, > >BTW. I suspect humidity levels are far different in other parts of = the > >state. I'm in Central Ohio. In the lake areas, humidity is = undoubtedly > >much higher during moderate weather. Also, I have no idea what = humidity > >levels occur in other people's homes here in Columbus. (I don't = service > >their pianos. <grin>) > > > > > I would love to have a controller for a DC type system that had = much > > > narrower limits. I know, for example, that rare bird hatcheries = have=20 > >units > > > that are calibrated to 1/10 of one percent humidity that power an > > > "electronic" fan (read no blades--some sort of vibrating plate) = combined > > > with an ultrasonic humidifer. I'd love to get my pinkies on one! > > > >Well, I can't boast 0.1% limits with my system (WOW!!), but I do = quite a=20 > >bit > >better than the specs DC boasts. I did a 100% non-DC-brand = installation on > >my concert grand, using a GE humidistat that cycles the system = adjustably > >between 40 - 44% (or occasionally as widely as 39 - 45%) when the = ambient=20 > >RH > >is in the upper 40's. The installation is fairly recent, so I = haven't yet > >been able to observe its behavior at higher humidity levels. I'll = give you > >an update in the spring if you're interested. > > > >Peace, > >Sarah > > > > > > > > > >_______________________________________________ > >pianotech list info: https://www.moypiano.com/resources/#archives >=20 > _________________________________________________________________ > Scope out the new MSN Plus Internet Software - optimizes dial-up to = the max!=20 > http://join.msn.com/?pgmarket=3Den-us&page=3Dbyoa/plus&ST=3D1 >=20 > _______________________________________________ > pianotech list info: https://www.moypiano.com/resources/#archives > ---------------------- multipart/alternative attachment An HTML attachment was scrubbed... URL: https://www.moypiano.com/ptg/pianotech.php/attachments/f6/14/d4/14/attachment.htm ---------------------- multipart/alternative attachment--
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