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Hi.
I've noticed a strange high pitched metalic sound sound coming from F#2 on my Yamaha UX upright.
You can hear it on the video, it is there pulsing with 3-4 beats per second.
I'm quite sure it was not present before and it is very obvious, the mostly at the back of the piano where the soundboard is.
I do not see anything in the piano that could resonate and I think it comes directly from the strings.
I could not determine if it is only one or both strings causing this.
What do you think could cause this?

Here is the clip:


Thank you!
Dejan

maybe it f#3 and f#4 enter into resonance there, because their wool damper is not fully covered the ALL 3 strings

No:( I've tested all F# and muted them also separately and there is no change...dampers are very good anyhow..this is, as you can hear , a very high pitch which seems to me that is coming directly from the strings.

I've tryed do separately dampen each unison string but it is hard to tell if only one string or both are causing this.
If I had to choose I would say the left string of both is to blame...

It there such a thing as faulty string perhaps related to copper wiring that could cause this?
Piano is 76'.

Yes, you can have faulty strings. Anything designed or made by a human being can be faulty. Also, if it IS a longitudinal mode issue, this tends to show up over time.

Peter Grey Piano Doctor

Sure, makes sense..I tryed to mute both strings separately..the wah wah wah sound is much more present on the left string but also the right has some if listening REALLY closely..when both ring at the same time the effect seems to be exadurated and it is really noticable.
This is only observable when the key is struch and hold to sustain...it could be that I bought the piano with this issue but I just did not notice until now.

If it is a strings related (which I'm quite certain) what does this mean in terms of fixing it?
Replacement of strings?

This is what happens when a technician makes small movements at the pins over time, without tightening the coil and knowing how to adjust the backscale segment. Right now, you do have tone going into the board. That is the organ-like, wooden sound that you hear when you play the note. The metallic wah-wah-wah sound is energy that is staying on the string and not getting transduced into the board. Essentially what you have going on is that the tone that is getting transduced is fighting with the metallic string sound that is staying on the string, and that is creating the falsness that you hear. If nothing is done, and the piano continues to be tuned using small pin movements, this effect will worsen over time and seem to "spread" to other notes.

The system simply needs to be rest. The solution is to carefully back off the tension, tighten the coil, and reset the pin as you bring all of the segments back to pitch in an equalized manner. Bass string do not like quick movements, so you have to be very careful. There is always a chance a string will break, but this is true anytime the piano is tuned.

Concert pianos, because they are tuned often and with small movements, can sometimes develop this type of sound within a season, especially when the strings are still somewhat new. Tightening the coils and setting the pins is part of normal pre-concert season maintenance protocol.

1. Make sure there is no foreign matter touching the strings. Check the bass bridge for this.
2. Gently push the hammer against the string, pushing from the catcher, not the hammer head. With the damper pedal pressed, lightly strum the strings, and listen for a difference in tone. If there is, carefully sand the hammer until there is not.

Than you guys, you helped a lot to understand what is going on!

I don't know if what I do is similar to what piano411 is talking about. I don't claim that my method has the same effect that piano411 claims, however, my method does cure cancer and will make every woman on earth want to fall in love with you.

Tuning pins twist on their own axis while being tuned. We want to end up with a pin where the twist has been relieved and the string is at the correct pitch. i start by going south before I go north. How much I lower the pitch before reversing direction depends on how tight the pin is in the block. Depending on how tight the pins are in the block that can be 20 cents or more. I start with a strong and steady pull downward, and then push rapidly up towards my landing point. (I am left handed). I continue the push until the pin lands on the target point. My theory is that the pin travels a sufficient distance that any twist in the pin is relieved. The pins are very stable and solid. When I am on my game, I can hit the target nine times out of ten. I usually know when I have hit my mark or not before I make my test blows.

Piano411 can let me know if this is similar to what he does.

WilliamTruitt, have you ever put a tuning pin in a vise and try to twist it? If not, please try that someday. No matter how hard you try, I'm sorry to say, you're not going to introduce any twist into the pin.

With that said, I agree with you that there is something in the tuning procedure that does feel like a twist of the tuning pin. I don't mean to argue the point, because it does feel that way. I would suggest that this feeling is the final turn on the coil getting set onto the pin, which in turn influences where the pin will naturally end up once you take the hammer off. Since you are tuning left handed on grands, you will naturally eliminate some of whatever that twist actually is just because of the physics involved. Actually, it also applies left handed to uprights if you press towards the pin block as you turn.

The "twist" as heard in the video above, or how you describe it "how tight the pin is in the block" will require a pretty large change in pitch to sound more resonant. A larger flight south, before heading north. Anyway, your perception of the twist and how the pin feels in the block is what directly gets altered when the pitch is dropped a 5th, the coil set, and then brought back into tension. I'm not sure if these other people are paying attention to those details or not, but since you do, you would notice immediately the improvement in feel. The pin will feel smooth, and you will be able to hit your targets better. That is to say, the pin won't get in your way.

So, we can talk about these things in terms of sound (aka resonance and tone) or in term of how the pin feels. When it feels like the pin is not being cooperative, then simply resetting the system will help. Reset the coil, and get that feeling of "twist" out of the pin.

I don't agree on the issue of twist in the pin, but I am not interested in arguing about it. Nor am I interested in dropping the tension a fifth. That said, if I have lowered the pitch a sufficient amount for the grip of a particular block, it does feel smooth and predictable, so much so that I can predict the result before the pin settles in place. And I will know by feel when I am not there.

Perhaps we are feeling the same thing, we attribute different things to it.

Yes, I am sure we are observing the same things and calling it something different. That part doesn't matter to me. I have no doubt. Based on what you've said, I know exactly what you are talking about.

I want to point out that once you have cleared the grip of the block, which could go down 20-30 cents--which is by most people's standard a huge amount--when you go to target, it goes smoothly into place. You know by feel where it is going even before you really have a chance to hear it. The important part is that moving the pitch that much does not create any instability in the tuning like most people would assume. In fact, the stability after that movement is very solid. If you didn't clear the block, you would have to fight with the pin jumping around.

As a point of clarity, dropping a 5th doesn't directly apply to the aforementioned issue. Dropping a 5th allows for dealing with the backscale segment and to be able to adjust the coil. When the bottom turn is pressing firmly against the string as it goes out to the piano, there is additional technique that is possible that isn't otherwise possible when these two parts of the wire are not in contact. When the coil is tight, there is simply better control. That control allows for a better tuning through technique. You can't really do this at pitch.

Anyway, at this point, it doesn't matter that each of us attribute the observations to. The point is, we are both observing something, and are most likely compensating for it in very similar ways when it comes to basic technique.

I also want to state, once again, that left handed tuning is an important aspect to what is going on. I am a right handed person, and it is more comfortable for me to use my right hand, but there are things that can be achieved left handed that can not be achieved on the right side of the pin. I learned to tune right handed. Still, there are things you will never feel if you are not on the left side of the tuning pin. That's just how it is. Also, there are some finer movements that are only available on the right side.

Thanks for the interesting discussion:)
Piano411 mentioned in the previous post that the "sound issue" can spread to other notes...and today indeed also G#2 started to develop similar issue, it was 100% not present yesterday since I inspected every note very carefully.
It is not as obvious as the metalic wah wah wah on the F#2 but it is present!
This is really strange, I hope tech will come soon to fix all of this..but for the future I would also like to learn how to fix it myself.

Settling in after a move? How long does that take; days, weeks, months?

I don't know...but I'm sure if the issue would be presnet when I got it home I would notice very soon..and now also one other note is affected, which was 100% not the issue yesterday...it is mild bit I'm afraid it will worsen over time and become like the one from the clip above.
So far all symptoms mentioned above by piano411 are present..
I do not think it has to do with moving but more with extensive playing (2-3 hours every day) and the symptoms seem to show up.

So it turns out that we really are talking about the same thing (after separating the back scale effort by dropping a fifth). Your description fits my experience exactly. The conventional wisdom says that making that large a pitch change in the dropping and coming back up will not be stable. It is when we get that feel that from the pin that we are both describing. I attribute that to the twist in the pin being gone, for you it is something else. My movement down and back up is pretty quick. and I must retain the pressure of pushing on the pin the whole distance. If I relax my pressure on the way, the technique does not work in achieving stability. I can make the move fast or slow, but it must be constant. And it is predictable.

I do think it is an advantage to be left handed in using this technique, it feels more natural to be pushing rather than pulling. No credit due on my part, just an accident of birth.

And now it is really spreading..now ALSO E2 is developing similar symptoms...ih happened at the specific moment while I was playing. What the heck is going on!! it's funny really but I'm starting to freak out a bit, this thing is slowly creeping up on my piano!
While F#2 is a wah wah wah like on the clip I posted, G#2 and from 5 minutes ago also E2 are more like a constant disonance high pitch steady sound...I can compare the sound to "striking two forks together" or something..
Well, I guess it's gonna explode tomorrow or something:)

Hello there! Sorry to hear your piano isn't happy... Given the location of the troublesome notes, it should be easy to have a look at the bridge in those positions. Bottom door of the piano should come off easily enough (careful; it's heavy!), then have a good look at the bridge pins and capping on the suspect notes. I'm a bit worried that what you're hearing is a split opening up in the cap; I very much hope I'm wrong. Posting a closeup picture of the bridge in that area would be very helpful

Hi, here are pictures of the bridge..I've also marked the section of the strings making "issues" ..and F#2 unison causing most issues wahwahwah on the video above in my first post.
I do not see any cracks in the bridge...I've also took a picture if the upper side ot the steings (top of piano). All looks fine to me?

Bridge is fine. It's perfect. It has nothing to do with that.

A normal tuning will clear up some of what your are hearing. But, it will come back if the tuner doesn't do a normal reset of the tuning system. The strings are fighting against themselves creating interference and falseness in the string sound. Drop the pitch, tighten the coil, and then all of the segments of the string proportionally to where they need to be. Otherwise, the back segment of the string will continue to cause problems.

For some reason, there are a lot of self-taught technicians that are petrified of lower the tension on the strings. If you can't find one that has experience doing this for concert prep or rebuilding, just ask around. Apparently, not many people in this forum have experience with this kind of work.

If you say you want the coils on tightened, or seat/set the coils, they will know what to do. You have to lower the tension on the strings in order to be able to do that.