[pianotech] PR follow up

[Andrew Anderson]

I would point out that piano requiring pitch correction over 100 cents  
probably never did achieve great stability after stringing.  I've told  
customers that a newly strung piano will need so much work.  You can  
do it now or string it out over the years and live with more  
instability and out-of-tune-ness.  Either way it will eventually get  
done.  I tuned a piano that was over 300 cents flat and they were  
quite certain it had never been tuned since it was purchased from a  
store in 1950.   The way this piano behaved, I am quite sure that it  
was never properly prepped.  I did my part and suggested that in 2  
months they might want to fine tune it again.  Sometimes they call,  
sometimes they wait and are happy for longer.

Andrew Anderson

On Aug 28, 2009, at 10:27 PM, David Love wrote:

> What else do you think accounts?  Soundboard compression?  When a  
> string breaks and the entire section goes out of tune is it the loss  
> of a few pounds downward pressure on the bridge?  If so, then simply  
> pressing down on the bridge should put the piano noticeably out of  
> tune.  But it doesn’t.   Additionally, when you destring the bass on  
> a piano where the bearing on the bass bridge is pretty much zero,  
> why does the tenor change so much in pitch?  On the other side, a  
> single string breaking makes a change of over 300 lbs of tension on  
> the plate.  The removal of the bass strings results in a net change  
> of 7000 -8000 lbs.  I would assert that it is primarily (if not  
> exclusively) the change in the way the plate flexes that is  
> responsible for the change in pitch.
>
> The stability after restringing has other issues including the  
> straightening of the wire at the terminations, the tightening of the  
> coils, loops and beckets, etc..  This is not really an issue on a  
> piano that has already achieved that type of stability.  The net  
> loss the comes about during a pitch raise is due primarily to  
> progressively added contractual tension to the plate.  Other factors  
> that affect stability are the ability for the technician to  
> stabilize the various string segments as Ron outlined in a previous  
> post, plus getting to a reasonable starting point from which to  
> start the fine tuning process.
>
> David Love
> www.davidlovepianos.com
>
> From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org]  
> On Behalf Of PAULREVENKOJONES at aol.com
> Sent: Friday, August 28, 2009 8:00 PM
> To: pianotech at ptg.org
> Subject: Re: [pianotech] PR follow up
>
> Some maybe. But you've tuned a piano immediately after stringing,  
> e.g. and there are all kinds of things happening that affect  
> stability. A radical pitch alteration, in smaller part, does much  
> the same thing, don't you think?
>
> P
>
> In a message dated 8/28/2009 9:58:14 P.M. Central Daylight Time, davidlovepianos at comcast.net 
>  writes:
> What about plate flex.
>
> David Love
> www.davidlovepianos.com
>
> From: pianotech-bounces at ptg.org [mailto:pianotech-bounces at ptg.org]  
> On Behalf Of wimblees at aol.com
> Sent: Friday, August 28, 2009 6:33 PM
> To: pianotech at ptg.org
> Subject: Re: [pianotech] PR follow up
>
> The most general phrases that seems appropriate to start the  
> discussion would be soundboard (de- and re-)compression over both  
> bridges, and the string segmentation tension differentials. Seems  
> enough. :-)
>
> Cheers,
>
> Paul
>
>
> Paul
>
> When I first started tuning 32 years ago, my dad told me that the  
> reason a piano goes flat after a pitch raise is because strings have  
> memory and want to "go back where they came from". Then I learned  
> that the reason a piano goes flat after a pitch raise is because the  
> soundboard compresses. Then someone told me that the bridge rolls  
> during a pitch raise.
>
> But my question are, how much memory does a string have, how long  
> does it take for the soundboard to compress, and when does the  
> bridge stop rolling?
>
> I have done some research on this, and my contention is that old  
> strings do not have memory, (a new one stretches, but not because of  
> memory), the soundboard stops compressing and the bridge stops  
> rolling as soon as the strings have been pulled up to pitch. After  
> that, it's just matter of stabilizing the tuning, just as you would  
> during a "normal" tuning. Is this the physics you're talking about?
>
> Have you done research on this? Have you taken an badly out of tune  
> piano, lets say 50 cents low, and done a pitch raise and fine tuning  
> in one setting, then checked it a day later, a week later, a month  
> later? Providing the environment in which the piano is sitting is  
> stable, what kind of results did you get?
>
> I ddi this about 10 years ago, and tracked my results, which showed  
> the pitch didn't alter. And I just did this on a 50 year old Everret  
> Studio sitting in my office. When it came in two weeks ago, it was  
> 45 cents flat. I pitch raised and fine tuned it. I just now played  
> it, and it's a little sour, but then it's sitting in front of an  
> open window and partly opened patio door. But in general it sounds  
> pretty good.
>
> Wim
>
>
> -----Original Message-----
> From: PAULREVENKOJONES at aol.com
> To: pianotech at ptg.org
> Sent: Fri, Aug 28, 2009 2:01 pm
> Subject: Re: [pianotech] PR follow up
>
>
> In a message dated 8/28/2009 6:36:33 P.M. Central Daylight Time, davidlovepianos at comcast.net 
>  writes:
> Please explain the physics as you know it that would account for this.
>
>

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