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Posted By: Radio.Octave dampers not lifting evenly with pedal - 12/19/20 01:40 AM
I've noticed that when I slowly press the sustain pedal, the dampers don't all raise at the same time. Also, then I release the pedal, some dampers touch the strings before others. This is causing some notes to buzz a bit. Is this an easy adjustment I can make myself, or should I just call my tech?
Posted By: piano411 Re: dampers not lifting evenly with pedal - 12/19/20 01:55 AM
This is how you set the damper timing for the key (when the key lifts the damper). To adjust when the sustain pedal lifts the dampers, you adjust the capstans under those levers. Normally, you make sure the damper timing for the key is correct, then you adjust the capstans afterwards. If one of those damper screws has loosened, the lever would be lower, which means the damper would raise before the others.

https://youtu.be/L5RiUK5OS_o?t=44

It depends how adventurous you are. Most people would hire someone to do it.
Posted By: BDB Re: dampers not lifting evenly with pedal - 12/19/20 02:07 AM
Kawai underdampers do not have capstans. Adjusting dampers so they raise evenly is not real easy, although I posted instructions some time ago. You should call your tech.

Keep in mind that flat dampers have different characteristics from wedge dampers.
Posted By: P W Grey Re: dampers not lifting evenly with pedal - 12/19/20 03:28 AM
Radio.octave,

What kind of piano do you have?

How old is it?

Has it had major work done on it within the last ten years or so?


Different makers have different setups for this. Also, after damper felt takes on a "set" from the strings, if you start moving these around and they "want" to sit differently on the unisons, you can find yourself in an almost endless chase trying to get things to quiet down.

Damper felt tends to get stiffer over time and therefore harder to re-regulate, and more buzzy. Also, regulation will not cure buzzy. BDB said it well that damper regulation is NOT easy to do really well unless you do a lot of it. Even a lot of techs cannot do it well.

Peter Grey Piano Doctor
Thanks, guys. It's a RX6. I just had it tuned a couple weeks ago. My issue is I'm getting the "buzzy" sound on certain notes as the dampers are coming down (at least that's what I think it is). I didn't seem to have this issue before the tuning. Is it possible that since the tension changed on the strings from tuning, it affected how the dampers contact them. It only seems to be noticeable on a few notes. If I play the problem note, and release the key extremely slowly, I can reproduce the buzzing sound. It happens just as the damper contacts the strings, immediately before the note is totally silenced.

I did tweak the capstan a bit, and now as I slowly press the pedal to raise the dampers, they are more in sync (there were only a couple that were obviously rising late). However, I don't think this was causing my problem since I'm still hearing the buzz.
Posted By: piano411 Re: dampers not lifting evenly with pedal - 12/19/20 06:47 AM
It's hard to guess without hearing it. Is it a metal on metal buzz? Sometimes the damper wire can buzz against the neighboring string. If you lightly move the damper head a mm in the opposite direction, you can check if this is the case. This is usually if the damper guide felt is too loose. There could be glue on the felt, if it is not a metal on metal noise. There could be a loose lead in a damper under lever. Just random guesses. A video would make it easier to tell.

Good for you, for evening up the capstans. I'm happy to hear when people can make improvements to their pianos like this!
Originally Posted by piano411
It's hard to guess without hearing it. Is it a metal on metal buzz? Sometimes the damper wire can buzz against the neighboring string. If you lightly move the damper head a mm in the opposite direction, you can check if this is the case. This is usually if the damper guide felt is too loose. There could be glue on the felt, if it is not a metal on metal noise. There could be a loose lead in a damper under lever. Just random guesses. A video would make it easier to tell.

Good for you, for evening up the capstans. I'm happy to hear when people can make improvements to their pianos like this!

Thanks. I'll try to make a recording to see if I can pick up the sound.
Posted By: P W Grey Re: dampers not lifting evenly with pedal - 12/19/20 02:49 PM
My guess on why you hear it more after the tuning is that previously the noisy out if tune unisons "masked" the buzzing of the damper felt. Now that they are nicer sounding, not only are you playing with more sensitivity, you are now able to hear more "defectualizms" in things not related to tuning. Therefore it "seems" like it wasn't there before but now is, whereas in reality it was there before but you weren't focusing on it. I have had this experience numerous times..."that wasn't there before, was it?...well yes it was". Okay, now I have to fix that.

Peter Grey Piano Doctor

P.S. No..."defectualizms" is not a real word...I made it up 😲
Posted By: Ed Foote Re: dampers not lifting evenly with pedal - 12/19/20 04:53 PM
Originally Posted by Radio.Octave
I've noticed that when I slowly press the sustain pedal, the dampers don't all raise at the same time. Also, then I release the pedal, some dampers touch the strings before others. This is causing some notes to buzz a bit. Is this an easy adjustment I can make myself, or should I just call my tech?

Greetings,
It is an easy adjustment for a novice to make. The difficulty is doing it without doing more damage than a tech's visit would have cost. I see far more DIY damage than improvement, so I see the odds of you getting what you want by doing it yourself as a first timer as slim. I speak for many techs when I say that " if you must go for it, be cheerful when you get our bill to repair it." So, here's one way

Do a closer check of your dampers. It isn't enough to say they don't lift together. Does one end lift before the other? Or perhaps, the middle rises first? Or, is more a scattershot result? Lift them all up with the pedal, then play a full bottom to top, two finger(get the sharps in there), glissando as hard as your fingernails will bear. Immediately begin lowering the dampers onto the strings, paying attention to the progression. Going slowly will allow you to pin point the last remaining string to be sounding. It will tell you if the dampers are mostly together with a few early and late ones, or if they are all over the place. This is the reverse of watching them lift and can tell more about how things are working vs appearing. Notice that some dampers begin moving while still damping (trichords), while others free the string at first lift,(blocks).
Going slowly enough , you may be able to detect which ones sing on landing. You can roughen the felt with a small strip of 320 silicon/oxide paper. I have had this problem in the recording arena, here. Close mics pick that yawp up. The abrasion therapy isn't a long term solution, but will buy maybe a year or two for a home piano. A flexible strip about 1" wide and 10" long will do it. You may want to check out the price of having some dampers replaced before getting too aggressive with the sandpaper.....

The above is all DIY guidance, woefully lacking in caveats, detail, and responsibility. Anyone with a RX6 that is having damper problems really should call their tech.
Regards,
Thanks, Ed. Yeah, I don't want to do anything too risky. I did pull out the action and look at everything, and to my untrained eyes, things look reasonably normal. There were a few stragglers that raised late after I pressed the pedal, but I tweaked them, and they look good. I'll have to take a close look as they come down. The one problem damper seems to be the D above middle C. Maybe it's not coming down evenly. (see video below)


Originally Posted by P W Grey
My guess on why you hear it more after the tuning is that previously the noisy out if tune unisons "masked" the buzzing of the damper felt. Now that they are nicer sounding, not only are you playing with more sensitivity, you are now able to hear more "defectualizms" in things not related to tuning. Therefore it "seems" like it wasn't there before but now is, whereas in reality it was there before but you weren't focusing on it. I have had this experience numerous times..."that wasn't there before, was it?...well yes it was". Okay, now I have to fix that.

Peter Grey Piano Doctor

P.S. No..."defectualizms" is not a real word...I made it up 😲

You're probably right about it being like this before, but the sound was masked. Here's a quick video where I tried to reproduce the sound. I play the problem note first, then a neighbor which seems better, then back to the problem. Do you hear the brief buzzy sound a split second before the note is totally damped? It's pretty subtle.

https://www.youtube.com/watch?v=qyI9z3SGy9s&feature=youtu.be
Posted By: piano411 Re: dampers not lifting evenly with pedal - 12/19/20 09:53 PM
Good video. Now it is clear what is being talked about. It is not a metal to metal buzz, or a wood to metal buzz, it is the sound of the felts and the string buzzing against a harder style damper material (and the wedge shape felt). The dampers need some tweaking, but, sadly, I think it is probably beyond the scope of DIY, in this particular case. It is not a difficult fix, but you have to observe, adjust some things, and then observe some more.
Originally Posted by piano411
Good video. Now it is clear what is being talked about. It is not a metal to metal buzz, or a wood to metal buzz, it is the sound of the felts and the string buzzing against a harder style damper material (and the wedge shape felt). The dampers need some tweaking, but, sadly, I think it is probably beyond the scope of DIY, in this particular case. It is not a difficult fix, but you have to observe, adjust some things, and then observe some more.

Thanks! Good to know. I will probably try to get my tech out at some point. thumb
Couple things you can observe:
Besides even lift - the damper needs to go up and down perfectly straight/vertical. If you can’t detect left or right travel on the damper block look at the damper wire as it goes through through the guide rail hole. It takes a special wire bending tool and knowledge of where to bend the wire- call a tech.
Besides up and down the wedges need to be centered and split wedges are not always equal width on both sides, also if strings are not level or the center string is not perfectly centered to the outside strings it takes special tool and skill - call a tech.
With the damper seated, pluck each string and if you detect an after ring some fine adjustments are needed - call a tech.
Sometimes you can simply iron the felt to flatten fuzzy fibers - call a tech.
There is more. Like if the damper block rotates slightly when lifted.
Sometimes on those notes close to the Lo tenor break, the wire spacing is wider at the back side of the damper block than the front making for some custom fitting.
If the split wedge is moving straight and perfectly centered on the strings, carefully raise it and when you let it fall you should be able to see the two outside strings move outward equally and center string remain still.
Posted By: piano411 Re: dampers not lifting evenly with pedal - 12/19/20 11:29 PM
Originally Posted by Radio.Octave
Good to know. I will probably try to get my tech out at some point. thumb
Yeah, I prefer it when pianists are willing to take care of their own pianos. There is so much that they should be able to do on their own. On this one though, if you look through what Gene_Nelson wrote, there are a lot of little things to pay attention to. While it is an easy fix, it is something that you have to check a few things out. It looks from the video that the right string is not damping like the other two. But, I'd have to put my hands on it to really check and see what is going on. Probably the damper head needs to be moved ever so slightly to the right. That is a wire bending operation, which also requires a subsequent bend to square the hammer, so it get really complicated to describe. There are a lot of things that can go wrong with this kind of adjustment.
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