Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Tuning stability

..."How do you know your tuning is actually stable?"...

Kees, that question, in the way it is worded, it's a bit odd. You do not really 'know' (for sure) when unisons will start sounding wrong (too many variables), but you can make sure you have done everything you could, in order to have your tuning as stable as possible.

..."Do you occasionally do checks by revisiting the customer later in the day, or next day, or next week to make sure your technique is actually working?"...

Yes, as others have confirmed.

..."In my experience it is possible to have all unisons in tune and stable against test blows, but a few of them still go out of tune after a couple of hours of normal playing."

Well, perhaps you are asking if it is 'normal' that '..after a couple of hours of normal playing..' a few unisons go out of tune? That should not be understood as the norm, but it may also depend on those many variables, as you may deduce from what has been posted.

Perhaps you wanted to ask what professionals do, so that their tunings are as stable as possible?
.

Most of the responses the OP's question are, to my way of thinking a breath of fresh air...honest...bowing to the complex and in some ways only partially knowable reality imposed by the interactive systems that comprise this instrument.

Kees, I have always felt that the questions about stability, my own questions included, jumped a key conceptual step. The questions always ask this or that about stability, but stability is never really defined. Most of the above responses consider stability to be a relative term, and in dealing with it as a relative quantity, begin to offer some hint of a definition.

In my view, stability refers to a band-width of musical acceptable imperfection, pretty darn close, but alive, and moving as the instrument moves within its environment and micro environment. There is some movement, there has to be some movement, but it must be musically acceptable movement.

Posts where stability pretends to perfection simply are not helpful, accurate or instructive, and give no hint as to a reasonable definition of the concept.

So, to those with more years than I at the lever, how about we try to offer some kind of a definition...is a quantifiable definition possible, or does quantifying it shoot the whole subjective aesthetic in the foot.

Jim Ialeggio

No, I wanted to ask what I asked, otherwise I would have asked what I wanted to ask.

Kees

Occasionally, if I need to return for another specific reason, but never to deliberately assess my tuning stability.

Woof!

Grrrr.

Just teasing Kees.

OK. I'll have a go.



When I have the opportunity to revisit a piano I tuned recently, I usually check the unisons to see if they still sound clean. Most of the time, they do.



If the pin is left "high" in the hole, and without sufficient positive tension differential, pin settling can occur over time (a few days?) that could reduce NSL tension to below the tension band limit and that would cause the pitch to drift.

Isaac refers to tuning "the knot" as a way to reduce this pitch drift.

What I was referring to when I said "What does that tell you" is that, even the professional engineers and producers who pay big money to use expensive recording studios full of engineers and expensive equipment, don't expect the piano to stay in tune more than a day, or even a half day, and will pay the extra expense to ensure it is at the highest level possible.

As for a quantifiable assessment of stability, I would say that unisons should not stray beyond the "swelling" or "blooming" quality. Yes, I know, that is qualifiable. (Is that a word?) So, let's use the PTG tolerance then. Nothing more than 0.9 cents off, left to centre, right to centre, and left to right. BTW, that's a pretty big window, but a 100% on the RPT exam.

Hope that helps.

When discussing tuning stability, I don't think it is wise to forget about the inharmonicity balanced temperament. If you compress or stretch the fit of the partials across the compass to extremes-any environmental change that increases this extremity-makes the piano sound out of tune quicker. If all the notes are centered in the middle of the sweet spot-any environmental caused changes in tension will take more movement to be noticed.

So if the piano is in the dry season and you tune with as little stretch as is musically acceptable-when the humidity rises the treble and bass will sound flat sooner. And if it is the humid season and you stretch the octaves as much as is tolerable-when it dries out the treble will just screech and the bass will sound pinched.

So if you float the basic pitch of a regularly tuned piano with the seasons you also need to "float" the stretch.

I do less and less test blows and more and more hammer technique to equalize tension in the NSL.

I buy and sell pianos and these pianos are an invaluable source of feedback about my tuning stability.

I was taught to pound the keys. Now I have learned to tune gently stroking the keys.

I don't like to pound the keys. By tuning and retuning the pianos I sell, I've learned that it's more stable to make a three or four passes tuning, that a one pass pounding the keys.

In grand pianos with high levels of friction in the NSL (understring felt) it is useless to pound the keys, the strings just do not render with a test blow, so it is better to equalize tension with the tuning hammer.

I'm with Rick Buttler when he says that unisons are to be first rough tuned before they can be fine tuned and that has a lot to do with stability.

Like most questions, the person answering will often consider what the questioner wants to know, not just what the questioner is asking. But feedback from the questioner is often needed to keep things on track...

Another thing that I will do is revisit a home piano a month or so later after replacing a string to bring it back up to pitch. (I charge enough at the replacement to cover this). This gives me a chance to see how the stability is.

Or for that matter anytime I tune a piano that I have tuned before is an opportunity to check stability. You expect to hear some slow beating in the intervals and a jump in the pitch across the break causing bad octaves. But there should not be any horrible unisons.

For my better home piano, I will have a couple imperfect unisons a few days later that I will touch up, and a few more a few weeks after that. Then it is fine for a few months until a humidity change overwhelms the dampchasers and things don't sound right across the break.

Doel, you did not ask what level of stability we achieve, but it seems it would only make sense to give this info, too.

Thanks everyone for the replies, looks like there are plenty of opportunities to check stability over time.

Would anyone care to expand on this and report the level of stability observed (measured in cents with an ETD, or beatrates determined aurally) with best practices over the timeframe of one or a couple of days?

Kees

What is noticed on rental concert instruments that are tuned day after day is that some tuning may stay for a certain number of concerts, very well, asking not an enormous work to maintain, then suddenly the tuning "explode" while nothing particular happened.

I agree on the description of stability as a zone where the tone is nice and the piano can be played without real annoying notes or intervals.

It relates to unison but also generally speaking to the way the piano is consonant. Some "medium" tunings can pass the seasons very well.
Very stretched ones can be very noisy at some point while retaining their progressiveness more or less, and unison.

A good tuning is something very firm, stable that gives confidence to the pianist.there is a specific energy that comes from that sort of tuning and a tuner "knows" the piano is stable.

I was happy to see the same pianos again and again with school work, and discovered how firm the foundations of a tuning can be set.
Hopefully, as it is annoying to be obliged to dismount the whole piano because the tuning have moved too much. It is necessary of course but we try to have that done late whenever possible.

Usually unison are not suppose to create audible beats. it
may happen but rarely.

Voicing of course impacts the longevity of the tuning. A well voiced piano will keep musicality even when the unison begin to meowwl ... !

Good unison have levels of 0.4cts diff between the couple and the "ballast" string, so I would think that 0.9 ct is yet not much audible.

Kees,

All you need is a tuning lever.

You don't ever need to worry about stability.

If a tuners tuning does not hold well, grasp your tuning lever and correct it. Play your piece. Repeat as needed.

If it were that simple Hakki I think every piano player (with particular reservation to the term "pianist") would be tuning their own piano. Don't you?

That technique would significantly reduce your productivity while practicing, and would upset the audience during a recital.

Last week I was at a concert where the World Premiere of a Piano Concerto were performed. In the middle of the concerto some of the unisons of the Steinway D began to drift. From there on it was a pain for the performer, for the conductor for the orchestra, for the audience and for the composer who was in the audience to listen until the end of the concerto. And yet we all applauded fiercely as if non of this has happened.

What did the tuner think of that?

I know him and I noticed he was there too.

Was this the first time it happened? No.
What did the administration do? Did they fire him? No.

Have you never attended a concert that the unisons did not drift until the very end? I bet not.

Without a bit of evidence to what extent the tuning of the instrument in question deviated, the mentioning of the superfluous details seems somewhat irrelevant. Having been to many concerts with a concert grand on stage I can't say I've been to any where the piano was so bad that the conductor, pianist, and composer in attendance winced in pain due to any shift in the tuning. I have seen some nasty percussive pieces give Steinway's, Bösendorfers, and a Yamaha their due in pounding it in. But only with minor unison drift not much worth mentioning.

I don't know what that tuner was thinking of the end result, and since it seems you didn't ask them, I suspect you may not either. If the piece in question was more along the lines of "piano abuse" I think the composer should be fired, or lose their commission, before the piano technician loses their job.

My unisons have never drifted in concerts so that someone could actually notice it...ever!!! I've been requested after previous mishaps by other technicians, but have never had a problem with the same piano/space. The tuning might take 4-6 hours, but when I am done, it's done: the pianist will never knock it out. That's what happens when you pre-bang on a tuning till it's done moving.

Perfect!! Bravo!!

That is what is expected. That is what ought to be.

Wish all the concert halls were lucky enough to have a tuner as good as you are. But unfortunately not all of them are as lucky.

But, but ...! If you beaten the strings so to take out all remaining available stretch the piano is unable to move anymore, and when it move that are the strings that begin to deform.
That job s done by the pianist, for the tuner's benefit usually.

I did use much time for tuning (generally more within 2 tuning s the same afternoon) But I am more or less sure that the highest stability may be attained in less than 3 hours.

ANd then be made "definitive"

Regards