Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Temperament and tuning stability?

For general information would someone please clarify why building up the tuning stability of a piano is a long term exercise, and why changing from one temperament to another affects it adversely?

Is it because of the strings, the pins, the piano adjusting to changes in tension, or what?

In a word: Yes.

Hello, I will try to be shorter than Opera Tenor .

The wire more or less loose its elasticity in 4-5 years, depending of the number of tunings also (it could be less) . So at the end of that period the pitch begin to be stable, fluctuating only with seasonal changes (HR and temp)
During that time if the tuning is done consistently (same aural tuner , or same tuning based on an ETD) bends install in the wire, and at the same time the "bed" of the tuning pin in the pinblock is more and more pronounced, the tuning pin is in its place.

It is not rare when bringing back in tune a piano, after a few years I have tuned it , to feel the pin coming back in place, and also the wire having a sort of "sweet spot".

With aural tuning, my experience is that different tuners are then less efficient for long term stability, even if I tend to respect the job of the precedent one if I find "traces" of a good tuning on an instrument.

AN element that also counts is the time spend by the tuner on the piano. I have seen Alfredo tuning a concert grand that was 3 years old and a little low in picth .
He spend 3 hours on it.

The piano was only tuned 1 year later, and that one is udes professionally for lessons and for the training of the pianist.

The first time I came to tune it again (so 1 year later) . I find a few unisons off, I did not even retune the whole piano.

Afterthat and with seaonal change it was necessary to do a complete tuning 3 months later, but that initial tuning did stay really solid.

I also can witness about pianos I tuned in a music school . I had 2 -3 large tunings/year , and I add to that "fast tunings", sort of touch ups, that I did in 30 minutes.

I also kept the action regulated and the hammers in "defensive" voicing.

When the contract finished 4 years later 14 months passed before I could see some pianos of the place again.
I was very surprised to find some of the grands with a 339 pitch but really playable and good "enough" for piano lessons.
Particularly no unisons horrible. And there are 2500 persons in that school , the instruments are highly solicited (I also have one broken string in 4 years)

It is not just "me" I have seen some other music schools where good tuners where working and where the stability of the tunings can be heard. there is something robust and "solid" in the tone of that kind of tuning, the pianist is at ease, On the contrary a less well settled tuning is unnerving (for some pianists not all are so sensitive to those aspects)

I like to have the pianos stabilized, then the tuning can be done once the year, and it is easy, it also allow to have more time for the little maintenance, cleaning, dust, little regulation...

Frankly I insist to tune often during the first years of the piano. Afterthat I will not be ashamed if the customer call me after 2 years (but he have to know that the action is may be less well regulated then and so some unwanted wear can happen)

Ok I'm going to take the opposite position! I change from ET to EBVT and back when the situation calls for it, and instability doesn't enter into the picture.

If a piano is not having its pitch changed, stability is a function of proper pin setting and string rendering, nothing else (assuming, of course, that the piano is structurally sound).

Loren, I agree. I've encountered only one exception. A piano that lives in a very stable environment which I've been servicing regularly for over 15yrs. The strings didn't want to make the small moves to EBVT.

Really? That's odd considering how small and varied the changes are.

I tune my piano in a different temperament frequently and never notice any stability problem with this.

Kees

For us non-pros, what's ET and EBVT?

ET = Equal Temperament - the 20th century standard

EBVT= Equal Beating Victorian Temperament - the hotly-contested brainchild of Bill Bremmer(see many, many threads here in the PTTF on the subject)

Thank you!

I suggest that we lisyen to the proofs, just show us how you tune . But we dont have the samemraning for stability. `and quality of tone. 2 different worlds.

with love. ..

Going back to my original question, I am beginning to suspect the "or what?" factor is the difference in perception from one tuner to another.

Loren and Kees have no problem with the pianos they have tuned. On the other hand, if he will allow me to bring him in as one among others, Johnkie has said he does not like another tuner interfering with a piano he is looking after.

My surmise is that Kamin and Johnkie would not tune a piano in exactly the same way, and both might say the other had upset the stability of their tuning. And I can't imagine either would be happy if the other changed in temperament.

Thanks for giving some sugar to the thread...

It may be possible, but probably no, as one can respect the tuning done before him.

Usually just looking at the way the tuner is working, or even just hearing it, one can have an idea of the final stability

(not long term, but basic stability, long term is different, and not a so easy goal, it may be more natural to some pianos/pianist/places than to others, but it just may take longer/more tunings in some case)

Generally speaking, the pianist have to accept what the tuner provide to him, nethertheless some pianists are really making differences, they notice what they prefer.

AT that point I understand they may prefer an UT than an ET version which is too bland or not harmonious enough.

Fior instance, when listening to that tuning I did while lowering the pitch, I can know it will be good for 6 months at best. The piano did move too much during the lowering (and tuning from above is agreable because the bridge raise and there is more downbearing pressure then, but it is rarely as stable as wanted only with a 1:30 job, in my experience)

Just a vertical piano, and no very exigent use of it, so the final stability can be a little under.

sample of tuning & corrections :

http://soundcloud.com/olek-4/unisons-corrections

I don't think this is the case. 100 year old wire still has its elasticity, more or less, after many, many tunings.

What technicians call "new strings stretching" is actually not the stretching of the strings at all. It is the gradual adjusting or compliance of the wire to the various curves and bends at the tuning pins, terminations, duplexes and hitch pins. After a few years, and a number of tunings, the bends in the wire have more or less reached their final state, and tuning stability is dramatically improved from the original state. Proper "string work" can accelerate the wire's conforming and leads to earlier and better stability.

This of course has nothing to do with the temperament used, I apologize for the digression but I thought this should be mentioned as it came up.

Well, I get the information from Klaus Fenner studies, the bends only could not lower the pitch as much...
The elasticity of 100 years old wire exists but is low (hence iH is high).

Klaus Fenner gave a method to use all the extra elasticity in 3 days by over stretching the wire by 4 notes series (from a M3 to a half step, ranging from the low end of the long bridge to the high treble)

I noticed after 4-5 years the pitch begin to be stable better.

Indeed when I say loose its elasticity, the string elongates, to, me.

There may be something in what you say about the bends and curves, whop had studied that to this analysis ?

(I agree my point is exaggerated, also)

With all due respect to Klaus Fenner, the string does not elongate over time. The string conforms to the curves and bends that it is forced into. In doing so, the tension decreases and hence the pitch drops. Overstretching the string will accelerate this process.

Try this: on a newly strung string, at pitch: Take a pair of pliers (duck bill work well) and grab the tuning pin coils. Turn the coils as if to tighten them. The actually do tighten and the pitch drops almost 1/2 step! Failing to do this at the time of stringing, it will happen gradually over time. Ditto at all the other points where the string is being forced around a termination or hitch pin etc.

This is what is commonly called "stretching of new strings": a mis-nomer. In fact there is very little, if any, non-elastic stretching going on. This is because the tension of the string is still well within the elastic range of the wire. If the tension is let down the string will return to its original length. Once the elastic limit of the string has been reached the string wire will actually begin to elongate. This happens far above pitch, just below the breaking strength.

Thanks for the answer, Jurgen I will try this today, as I have just a freshed stringed piano.

I had understood that it had to do with the metallurgy of the wire, when it is under tension (and it is a domain I dont master at all ).
Of course the wire is kept under its elasticity limit (near of is said to be better to have a purer tone, as it may decrease iH or make the spectra more clean) .

Is not the elasticity raising with more tension ? If the elasticity can differ, the way the string come ba&ck to its previous lenght may differ also (?)

Then, we have the stretch parameter which is included in the scaling spreadsheets , what does it relates too is it a fixed dimension (that would explain how first class bass winders send us perfectly aligned bass wire )

Indeed if the wire stretch it may loose bit in diameter, it is said top be the case on old wire.

Do you have any study to support what you say please ?

Anyway, what you state there is a very strong argument for not to change temperament , (nor tuner) if you are pleased with the piano.

The bends and kinks in wire are felt by the tuner after some years, that strange BTW as I always wondered how it was possible that a note come back to its original pitch when returned in its original bend (in agrafe for instance) .

I like to find a document that give the part difference between the stretching due to the tension and elasticity installation, and the one due to the bends (indeed there is a long piece of wire around the tuning pin, enough to lower the pitch.

I am a practical tuner so I am mostly curious to understand of have an idea on how the things may be working.


Thank you.

Jurgen,

From my own background knowledge, I would agree with you: Stretch (i.e. deformation) only occurs in the plastic range, and since the strings are still in the elastic range, they don't stretch.

But there have been many posts on this forum about so-called creep. They state that creep is a permanent deformation, that it occurs even in the elastic range, and that the rate of creep gradually decreases.

A few examples:

Emmery's reply (third post) in this thread:
https://www.pianoworld.com/forum/ubb...g%20does%20it%20take%20a%20new%20pi.html

Emmery's (4th post) and krikorik's (14th post) in this one:
http://www.pianoworld.com/forum/ubbthreads.php/topics/1573779/Aggressive%20String%20Stretching.html

And another that also contains a link to explain the mechanism(s) of creep:
http://www.pianoworld.com/forum/ubbthreads.php/topics/1711072/1.html

Are you saying that those posts are incorrect?

This discussion pops up every few months, and it would sure be nice to obtain some clarity on "creep or not".

Thanks Mark, I cannot find the link you talk about, in the last thread (did not go thru the whole pages, too) .

It seem to appear that creep factor is negligible, in regard of pitch lowering, even if real (I call it the "hardening" of the wire)

In any case then, the main effect of stretch may come from the bends and turns who really "stretch" the wire.

The metal may also change its organization when put under stress.

I noticed that Paulello wire is stabilized very soon, if compared to Roslau.

Difficult to find studies on the subject. Discussions, yes, but searches are not so evident.

does a piano wire deforms

"creep" seem to be related to stress under high temperatures, does not seem to apply well for piano wire.

Then, one technique given to me for massaging new wire is to use a wooden T shaped piece than the stringers can push on while standing (the piano is then vertical).
The plain wire are then massaged up and down, and the job have beenn "done well if the strings are warm" afterthat (traditional method that may have been used in some piano factories)

Warmness... is it a sufficient level of warmness to modify something in the string metal itself ?