DC / value ??

Don pianotuna@accesscomm.ca
Wed, 17 Sep 2003 13:50:27


Hi Carl,

Because the piano started *out* at 42% the summer bulge in pitch was that
much less. My oberservations over many years tell me that for each 5% of
humidity change the pitch at A4 will change about 4 cents, *if* the piano
is allowed to stabilize at the new humidity. Just how much time that takes
is an unknown factor.

At 02:19 PM 9/17/2003 -0500, you wrote:
>Similar observation here. Piano teaching facility has a Kawai piano
>in one of the rooms. Recently I installed a DamppChaser unit to try
>and educate the owner on the value of same. Doing the fall tuning,
>I found that it was sharp as well, but not as sharp as you describe.
>When we talked, I made mention of this to the owner, and he was
>very quick to point out that the unit had in fact been unplugged all
>summer.   My reaction was . . . uh, ??. I'm guessing that because it
>did have the benefit of the DC for the time before being unplugged,
>it probably was in a better position to handle the extra humidity which
>was evident in our area this very hot and humid summer. By the look and
>body language of my customer, I have serious doubts that he buys this
>theory.
>I'm very curious as to what the condition of piano might have been if it was
>
>plugged in those extreme summer days. I had installed this unit at my cost,
>in
>hopes that there would be significant benifit, which could result in the
>installation
>of many units, in the rest of the school. Very difficult to overcome the
>resistance
>of spending this much money at best, and now there is the appearance that
>they
>are of little or no benefit. What bothers me some, is the fact that I like
>to tune to
>440, but as these pianos range so much away from pitch, it obviously takes a
>lot
>more work to maintain them. As these pianos are quite new, you would expect
>that standard pitch should be no problem. I'm now thinking that I should
>tune a
>little sharp, ( 442 ? ) so that they will be easier to stabilize. Generally,
>they are played
>alone, so I don't suppose it would cause any problems.
>If tuning took place later when the heat was on, pitch might lower
>naturally, but teaching starts first week of Sept., and request to tune
>was for 3rd. week of Aug., far from any dry heat which is what comes
>from a furnace.   ????????
>Curious how other guys handle this situation.
>
>Carl / Winnipeg
>
>Clyde Hollinger wrote:
>
>> Friends,
>>
>> I'm back after a two-week vacation to the Canadian Maritime provinces.
>> Nice trip!
>>
>> One of my tuning jobs today was a Kawai UST-8 with a complete
>> Dampp-Chaser system, a piano I've been tuning annually since 1995, in an
>> elementary school.  Even though the system seemed to be working properly
>> (the dehumidifier was cranking out the heat), the tenor plain strings
>> were up to 11c sharp, making a pretty nasty sounding piano -- before I
>> tuned it, of course!
>>
>> Here's my two best guesses why this was so.  Either the piano was
>> unplugged all summer and recently plugged in, or the tank got empty and
>> was just recently filled.  The teacher wasn't there for me to ask.  Both
>> would have the same effect, methinks.
>>
>> Long shot guesses would be that it's just been too humid for the piano
>> to keep after, or that the system isn't working properly.  Thoughts?
>>
>> Personal notes:  I developed tendonitis in my tuning lever shoulder two
>> weeks before vacation.  I didn't go to the doctor, since I thought it
>> would have time to heal while vacationing.  It didn't.  This morning I
>> tore a muscle in my right leg calf, which hurt pretty much, so I went to
>> the doctor and we discussed both problems.  He wants me on crutches, but
>> we can't do that because of the shoulder, so I hobble pretty badly as I
>> walk.  I'll be starting physical therapy for the shoulder later this
>> week.  All while trying to do four weeks' worth of tuning in two!  Fun,
>> fun!
>>
>> Regards,
>> Clyde Hollinger, RPT
>>
>> _______________________________________________
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>
>_______________________________________________
>pianotech list info: https://www.moypiano.com/resources/#archives
>
>

Regards,
Don Rose, B.Mus., A.M.U.S., A.MUS., R.P.T.

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REGINA, SK
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