temp change=how much pitch change?

[Bob Hull]

Hi Terry,
I agree with you that the DC system does help this, I
was thinking however of the more rapid  temperature
change scenarios from spot lights and other things.
When strings heat up or cool down the pitch will
change faster than a humidity control system can deal
with.  One hall where I tune has a huge garage door at
the loading dock end of  the stage.  When that is
opened for the percussion truck to unload in winter it
can change fast and the piano with it.  I usually try
to schedule around that.  

Bob Hull
--- pianolover 88 <pianolover88 at hotmail.com> wrote:

> <<I don't know what "damp-chaser" means>> You're
> kidding, right? Humididty 
> swings are considerably more threatening to piano
> tuning stability than 
> temperature. But the (full) DC systems stabilize the
> soundboard and keep the 
> moiture content consistent, so surrounding temp and
> humidity are not as much 
> of an issue, than a piano without a DC system.
> 
> Terry Peterson
> 
> 
> 
> ----Original Message Follows----
> From: Bob Hull <hullfam5 at yahoo.com>
> Reply-To: Pianotech List <pianotech at ptg.org>
> To: Pianotech List <pianotech at ptg.org>
> Subject: Re: temp change=how much pitch change?
> Date: Sun, 11 Feb 2007 20:20:07 -0800 (PST)
> 
> I don't know what "damp-chaser" means either nor do
> I
> follow Diane's tune it 4 cents flat.
> 
> A chart of temperature, humidity and pitch change
> results may be somewhat useful in terms of general
> tendencies however, I think that each piano and each
> room will react a little differently.  The speed of
> the temperature change, the reason for the
> temperature
> change (lights or hvac and type of hvac) all will
> have
> an impact the the amount of pitch change. Also, how
> long the piano has been at a previous temperature
> makes a difference.  Plate is a large heat sink and
> slow to change compared to  strings.
>     A specific example in my own customer base
> includes
> a very delicate tuning situation with a Hamburg D in
> a
> small recital hall.  The lights in that room will
> run
> up the temperature quite a ways before the
> thermostat
> will react.  Due to the small size of the room I
> cannot allow the temperature to change over .5
> degrees
> without changing the  pitch level drastically.  I
> keep
> a thermometer on the piano so I can jump up and
> adjust
> the lights to keep the temperature close enough.
> 
> Bob Hull
> 
> --- "John M. Formsma" <john at formsmapiano.com> wrote:
> 
>  > Huh? maybe a little more elaboration.
>  >
>  > JF
>  >
>  > pianolover 88 wrote:
>  > > Dampp-chaser.
>  > >
>  > > Terry Peterson
>  >
> 
> 
> 
> 
>
____________________________________________________________________________________
> No need to miss a message. Get email on-the-go
> with Yahoo! Mail for Mobile. Get started.
> http://mobile.yahoo.com/mail
> 
>
_________________________________________________________________
> Invite your Hotmail contacts to join your friends
> list with Windows Live 
> Spaces 
>
http://clk.atdmt.com/MSN/go/msnnkwsp0070000001msn/direct/01/?href=http://spaces.live.com/spacesapi.aspx?wx_action=create&wx_url=/friends.aspx&mkt=en-us
> 
> 



 
____________________________________________________________________________________
Get your own web address.  
Have a HUGE year through Yahoo! Small Business.
http://smallbusiness.yahoo.com/domains/?p=BESTDEAL