[pianotech] DC (was:To unplug or not to unplug)

Ron Nossaman rnossaman at cox.net
Tue Jan 25 05:50:41 MST 2011


On 1/25/2011 12:37 AM, Jon Page wrote:

> OK, I mis-spoke. It was not the humidity that affected the tuning,
> it was the temperature.
>
>
> Please excuse my imprecision on vocabulary/concepts.

Sorry Jon, but it is. That doesn't do us all that much good with tuning 
though, because the darned thing still moves as we tune. The frustrating 
thing is being unable to do anything about it. We open the DC equipped 
piano, and wait for it to go sharp as the strings cool. Then we try to 
tune it as the heat or A/C cycles. When we close it up after the tuning, 
it heats back up and goes a bit flat. It's just a limitation of the 
circumstance. A super climate controlled room would still go through 
those short term heat fluctuations as the system cycled. The alternative 
is finding the uncontrolled piano 30¢ off pitch in the tenor and low 
treble every single time we tune it, knowing that it's sounded pretty 
wretched for most of the time since the last tuning.

We have these marvelous electronic devices available today, that can 
give us measurements of tuning effects with a precision far beyond our 
capabilities of controlling the atmospheric conditions that produced 
them. It's like a teacher that has made it known that no matter what is 
turned in, there will be no 100% scores graded. So we have to grade on 
the curve. Short term temperature variations are a fact of life whether 
a DC is present or not, and at whatever level of precision we may be 
able to reach, we still have to grade on the curve at some point.

Ron N


More information about the pianotech mailing list

This PTG archive page provided courtesy of Moy Piano Service, LLC