Piano World Home Page
I purchased an Estonia L190 back in June of 2007.

I live in Oregon and had it in a house for a couple of years (until July of 2009). We then moved to a house not too far away from our old house. I have 2 older grands that are stable in their tuning, but the Estonia is still going out of tune, noticeably, every three months.

Is this normal? Or is there an issue with the piano?

Thanks in advance for your comments.

PS. The relative humidity in the room is consistent between 40% and 48%.
after 2 years or 6 tunings, the piano is stable, it may also depend of the technique used by your tuner.

It may depend a lot of the amount of stabilisation done at the factory, and in the shop prior to delivery.

After 4 years the wire hardly loose any lenght and the mistuning may be only due to seasonal changes, insuffisent pin/string setting, or extra heavy playing.

That said for concert venues the piano is still tuned twice, one before rehearseal and once before the concert, when things are done to the best.

good if you have a consitent moisture level, 40-48 is very good

The term for what is happening with the wire is called "creep" and it occurs in most all materials that are subject to stresses and/or temperature fluctuations. What differentiates it from "stretch" is that it is a permanent deformation of the material at stress levels below the yield strength. There are different stages of creep but as the process of work hardening and annealing balance out, the rate of creep decreases to a very low constant. On piano wire this is a year or two after being under tension. I will tune a new piano slightly higher than normal pitch if the customer does not mind. This helps to reduce the time for the strings to stabilize a little bit.

Years ago I knew a tech in Europe that actually had a stringing jig made from old pinblocks cast into concrete in his work shop. It was about 30 feet long. He kept wire prestrung under tension on it and after a couple years removed it. When he installed this wire as replacement for broken strings he claimed it was very stable and did not require the extra return visits to tune. He charged much more for this service obviously but many of his clients were happy with not having a rogue note come back and haunt them between the more frequent tunings/touch ups.

I just dealt with an Estonia 168 here in Vancouver with stability problems in the tuning.

This instrument has front and rear duplex scaling. Because of multiple tunings that did not equalize the strings over these areas I found a lot of built up energy within the duplex, both front and rear. If this negative energy is not released properly, after a tuning the instrument will not remain in tune for long, if at all. What you are getting then is the “creep” Emmery is referring to.

I spent between 3 and 4 hours working over a 2.5 octave area beginning at B below high C and up into the 7th octave. It took quite some time to get the string to render over these areas……. some 8 passes or more….tuning down, as the instrument was flying sharp continually……..

Interesting to note that in these instruments the center section of the treble is with agraffes and each string is tied as a single with a German loop. Beginning at B5 the strings are loop tied, and with the V-bar configuration.

To find out if the duplex has trapped energy, the duplex scaling would have to be plucked to hear if the strings are in tune with each other relatively…….if they are not then this is part of the problem.

I also found too much variation in the RH of the room. After moderating the environment of the room, the instrument has settled somewhat but the customer is not out of the woods just yet.

A tuning every 3 months on a new instrument in not out of the normal.
Another factor here is the comparison with old pianos. You don't mention what they are and how old they are, but sometimes an older piano with a kind of dead soundboard that doesn't have much life to it will be extremely stable, but it doesn't sound so good. Also, a new piano with a bright tone will tend to make slight unison changes much more noticeable.

I suspect these might be contributing factors to your experience. But your piano tuner should have some opinion about this!
How is the piano going out of tune? If the unisons aren't staying set, then I'd be more worried about the tuning techniques. But if it's just sections of the piano that seem out of tune with the rest of the instrument, then it may still be settling. In cents, how far off pitch is the piano (your technician should tell you this)? Are we talking a few cents off or 30 or 40 cents? Is the piano going flat or sharp?

I tune a lot of new Yamahas in customer homes and I see quite a bit of variability in the "settling time". Some of the U1 uprights are just rock solid after only one or two tunings. Others can take a couple of years to settle in.
It occurs to me that how long a new piano stays in tune may well depend on how long it sat in the show room.

For instance, if a piano were manufactured and strung only a month or two before the customer places it into his/her home, the tuning may not last as long as a piano that sat in a show room for a year or two.

This show room "aging", even if not being played very often would have a similar effect to the technician who "pre stretches" his wire with weights.

Roger
Originally Posted by Emmery
The term for what is happening with the wire is called "creep" and it occurs in most all materials that are subject to stresses and/or temperature fluctuations. What differentiates it from "stretch" is that it is a permanent deformation of the material at stress levels below the yield strength. There are different stages of creep but as the process of work hardening and annealing balance out, the rate of creep decreases to a very low constant. On piano wire this is a year or two after being under tension. I will tune a new piano slightly higher than normal pitch if the customer does not mind. This helps to reduce the time for the strings to stabilize a little bit.

Years ago I knew a tech in Europe that actually had a stringing jig made from old pinblocks cast into concrete in his work shop. It was about 30 feet long. He kept wire prestrung under tension on it and after a couple years removed it. When he installed this wire as replacement for broken strings he claimed it was very stable and did not require the extra return visits to tune. He charged much more for this service obviously but many of his clients were happy with not having a rogue note come back and haunt them between the more frequent tunings/touch ups.


Thanks for pointing this, Emmery. Is the wire loosing some of its diameter in the process ? I 'd like to find experimentations documented.
K Fenner method for that is to raise the wire so it is nearer the end of the elastic limit i.e a full M3 in the first plain wire, a m3 an octave higher, and 1/2 step less up to the treble, with groups of 4 notes left in that stress for 8 hours, then back. I've done it once and did not like the tone change, but the piano was stable immediately.
© Piano World Piano & Digital Piano Forums