<html> <body> A DC system really can't be effective in a grand without a string-cover.  Even then it doesn't really help the front key-pins.  An undercover is recommended if the place has forced air heating/conditioning. My wife's concert grand wouldn't stabilize until I made both additions above. Andew Anderson At 04:45 PM 2/17/2008, you wrote: <blockquote type=cite class=cite cite="">Yes, I do think whole room units are better. DC units do not address pin blocks in grand pianos. I had a customer with a 5 year old Kawai RX series with a DC unit installed and had loose tuning pins. I read 15% humidity in his home. I instructed him to purchase a humidifier immediately. With 6 weeks at 40% humidity the tuning pin were back to normal tightness. I got it back in tune and now it stays in tune. I have found that DC units do a fairly good job in upright piano.   Al Guecia   ----- Original Message ----- From: "Prof. Euphonious Thump" <<a href="mailto:lclgcnp@yahoo.com">lclgcnp@yahoo.com</a>> To: "Pianotech List" <<a href="mailto:pianotech@ptg.org">pianotech@ptg.org</a>> Sent: Sunday, February 17, 2008 5:21 PM Subject: Whole room humidity control better than Dampp Chaser. ( Right?) > Dear Everybody, >     My friend with the Bechstein grand someone's > giving him wonders if a Kenmore dehumidifier and a > digital hygrometer on the wall would be better than a > Dampp chaser at protecting his "baby". >     I'd certainly think so, but wanted to ask here, > as well. >    Thanks! >     Thump > > P.S. A he lives in an apartment, I imagine he has  a > reasonably small room he can close off for it. > > > > > >      ____________________________________________________________________________________ > Never miss a thing.  Make Yahoo your home page. > <a href="http://www.yahoo.com/r/hs">http://www.yahoo.com/r/hs</a> > </blockquote></body> </html>