<html> <head> <style> .hmmessage P { margin:0px; padding:0px } body.hmmessage { FONT-SIZE: 10pt; FONT-FAMILY:Tahoma } </style> </head> <body class='hmmessage'> Hi Don, what were the results of your experiment with the hydrocel unit? Your region seems to be very extreme concerning humidity changes! Perhaps you could do a further experiment, using two of the units: one on the bottom, one on the upper side of an upright. In my area the humidity swings between about 30 % to 85 % (in rooms) and for these conditions the hydrocel is enough and a must for floor heatings. I used to live in a house directly on a riverside and had a floor made of wood. I.e. that in summer it was quite wet and in winter the wooden floor soaked all the humidity out of the room. I measured 27 % in winter. I installed one unit on the upper side of my private upright at the begining of the heating period. At that moment the piano was out of tune but I wanted to wait with tuning until the heating was on for at least one week (yes, I am lazy - instead of tuning twice). After one week the tuning was much better, so my piano tuned itself :-) Which material is used for the active part of hydrocel? No idea. Bt the main thing is it helps. Gregor > Date: Sat, 6 Sep 2008 07:44:59 +0000 > To: pianotech@ptg.org > From: pianotuna@accesscomm.ca > Subject: RE: Why After Two Years..... > > Hi Gregor, > > I'm glad to hear it helps. In most of North America the swings are so wide > that it simply can't keep up with the "load". I've done "hands on" > experiments with one in an upright piano, just to make sure. > > I do wonder if the "active" part of the hydrocel is one of calcium sulfate, > calcium chloride, cobalt chloride, silica gel or some combination of them. > > I'd love to experiment with this product called Art Sorb. > > http://www.cwaller.de/english.htm?howto.htm~information > > There is a product called Music Sorb but their own test results show that > it is inadequate to control a piano year round (i.e. staying within a + or > - 2.5% "window"). It does appear to smooth out humidity, so it is of some > use. Have a look here: > > http://www.musicsorbonline.com/PianoTest.htm > > What helps here is to isolate the piano--for uprights a plastic back > cover--and for grands bottom "dust" covers made from stretchy fabric--and > string covers. > > The next line of "defence" is a dehumidifying only system such as the > moisture master with adjustable controller. > > The very best system appears to be the Damppchaser, where in extreme > climates like mine (4% to 84%) an upright in a home may show pitch change > of less than 2 cents per year on any note in the instrument. > > At 10:24 AM 9/6/2008 +0200, you wrote: > > Yes, it´s the Hydrocel system. Cheap, simple and works well. The > tuning lasts longer and the pins get tighter. The customers fill it with > water in winter (i.e. heating period) and ignore it in the summer. In > summer it soaks humidity if the air is wet and gives it free when it´s > getting dry. I think it´s a good alternative to Damp Chaser, but it might > be too weak for very dry regions. Can´t say that because it´s not so > extreme dry in my area. Anyway: it´s better than nothing. > >Gregor > Regards, > Don Rose, B.Mus., A.M.U.S., A.MUS., R.P.T. > Non calor sed umor est qui nobis incommodat > > mailto:pianotuna@yahoo.com http://us.geocities.com/drpt1948/ > > 3004 Grant Rd. REGINA, SK, S4S 5G7 > 306-539-0716 or 1-888-29t-uner > <hr />Discover the new Windows Vista <a href='http://search.msn.com/results.aspx?q=windows+vista&mkt=en-US&form=QBRE' target='_new'>Learn more!</a></body> </html>