Allow me to say some thing different from yours guys :) Wood is "viscoelasticity" material(I know I am good at misspelling, but not this time, I got this English word from a material expert).under new/different loading,viscoelasticity material will deform(change its shape) when the time goes by, that means, after a pitch correction, the pitch will change for a certain period, not only immediately. I first noticed the viscoelasticity character of wood when I did research on soundboard vibration. I tired to get the modulus of spruce by adding load on a piece of wood. the wood simply keeping shinking/yieling under loading--for a long time! I did more serious research on the subject and found that the viscoelasticity character of wood has been proved by some scholars on wood. Even though the viscoelasticity character of wood is hardly noticed by our tuners, there are still one or two clues for this: 1, using a tuning machine, raise the pitch of a note (ideally in the middle range, or the center of the soundboard), and keep playing that note very softly, most likely, you will see pitch dropping for a few seconds, why the pitch drops afterwards? 2, when doing a pitch raise, fast tuner usually see more pitch drop than slower tuner; or fast-tuned notes drop more than slow-tuned notes. The reason for that is fast-tuned note doesn't have enough time to drop. In other words, viscoelasticity material always needs time to find its new position. Well, I said too much about the "viscoelasticity", let me say something about my preferred way to do pitch raise. when concert instrument needs pitch raise, I usually try to do a "fine pitch raise" first, make sure the tuning is playable but not perfect, then give the piano some time to find its new balance. One or two days later, I fine tune it. A touch-up may needed after fine tune (mostly for tuning stability).the tuning will last much longer (we usually tune concert pianos once a week, due to the busy schedule). To separate the pitch raise and fine tuning gives the soundboard enough time to find its new balance, also to give the string enough chance to equalize it tension. Merry Christmas to every one! Baoli Liu,RPT Madison Chapter --- pianolover 88 <pianolover88@hotmail.com> wrote: > Oh yeah....MERRY CHRISTMAS!!!!!!!!!!!!!!!!!!!! > > Terry Peterson > > > > ----Original Message Follows---- > From: bobdavis88@aol.com > Reply-To: Pianotech <pianotech@ptg.org> > To: pianotech@ptg.org > Subject: Re: Let's Get This Settled was How to > explain a > pitchadjustment..and! > Date: Wed, 21 Dec 2005 12:48:31 -0500 > > David Love says: > "Once you correct the pitch and do a > fine tuning, all other things remaining constant, > the piano will stay in > tune." > > I think so too. My approach is "Rough tune it 'til > it stops moving, then > fine tune it." Maybe that's once, maybe it's three > times - depends on how > good my calculations/guesses are for overshoot. > However, if I get it settled > down (+/- about a cent) before I fine tune, if I go > back a year later and > the humidity has been kept stable by whatever means, > the piano sounds really > good. It's less expensive for the client to be > paying for rapid pitch > adjustments than a full return trip in a few weeks. > > Bob Davis > > -----Original Message----- > From: David Love <davidlovepianos@comcast.net> > To: 'Pianotech' <pianotech@ptg.org> > Sent: Tue, 20 Dec 2005 20:56:41 -0800 > Subject: RE: Let's Get This Settled was How to > explain a pitch > adjustment..and! > > > My experience says it doesn't matter. Once you > correct the pitch and do a > fine tuning, all other things remaining constant, > the piano will stay in > tune. The piano doesn't really settle. Moving the > piano cross country may > challenge the piano in terms of EMC but nothing > more. An upright can go out > of tune with a move across the room because the four > point weight bearing > can tweak the stresses in the case a bit if the > floor is not exactly level. > The three point weight bearing of a grand makes it > immune to such problems. > > David Love > davidlovepianos@comcast.net > > -----Original Message----- > From: pianotech-bounces@ptg.org > [mailto:pianotech-bounces@ptg.org] On Behalf > Of Alan Barnard > Sent: Tuesday, December 20, 2005 8:25 PM > To: Pianotech > Subject: Let's Get This Settled was How to explain a > pitch adjustment..and! > > Terry's post begs the question (and please > understand I ain't challingin' > nobody on nuttin' ... I'm just seeking information > and opinions and > science, here) ... > > Do a piano really need time to "settle" after .. > > 1. Big pitch change? > 2. Small pitch change? > 3. Moving it across country? (other than > environmental acclimation) > 4 Moving it across the room? > > I have been under the impression--and it may be > altogether wacky--that > every change that is going to occur in the piano > occurs immediatly upon > cranking the pin. I thought someone (Dr. Sanderson, > perhaps) tested this > and proved it. > > So an adjunct question: Let's say we find a piano 15 > cents flat. We pitch > correct and fine tune and walk out the door with a > follow-up appointment > set for three months. When that day arrives, for > those who have set such > appointments, is the piano any flatter or more sour > than it would have been > if we found it A440 but still came back in three > months? > > Same question, only now the piano was originally 35 > cents flat. 60 cents? > 120 cents? > > Certainly I've restrung pianos and found them pretty > sick in a couple of > months but have always attributed that to new wire > stretch, not tension > settling. > > Helmet on, raincoat on, rubber duckie in hand, I > await your missives, if > not missiles ... > > Alan Barnard > Salem, Missouri > > > > [Original Message] > > From: pianolover 88 <pianolover88@hotmail.com> > > To: <pianotech@ptg.org> > > Date: 12/20/2005 6:24:24 PM > > Subject: Re: How to explain a pitch > adjustment..and! > > > > Depending on the amount of PR, ususally more than > 12C, I always schedule > a > > "follow-up" tuning in 1-3 months, explaining that > after restoring all > that > > loststring tension, the piano now must "settle" > and adjust to that added > > tension, and it some shifting of will occur. So > the follow-up is crucial > in > > building long term stabilty. And that tuning will > leave the piano much > more > > stable because tuning pin movement will be much > smaller than during the > > initial PR and tuning. Again, never a problem. > Yes, it does help to have > a > > high confidence level and be able to effectively > communicate and impart > > information to your client in a clearand concice > manner. I am a salesman > as > > well as a technician; that has made the > difference between just getting > by > > to making a six figures. > > > > Terry Peterson > > > _______________________________________________ > pianotech list info: > https://www.moypiano.com/resources/#archives > > > _______________________________________________ > pianotech list info: > https://www.moypiano.com/resources/#archives > > > _______________________________________________ > pianotech list info: > https://www.moypiano.com/resources/#archives > __________________________________________________ Do You Yahoo!? Tired of spam? Yahoo! Mail has the best spam protection around http://mail.yahoo.com
This PTG archive page provided courtesy of Moy Piano Service, LLC