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Beginning of January the dealer is coming to install new damper felts on a new Estonia 168.

Damper noise is very annoying when the tricord dampers come DOWN: pedaling, staccatto or portato playing in that section is quite awful.

First the dealer thought the sides of the damper felt was somewhat uneven and intended sanding them. Further thinking made him order new Renner damping felts from Talinn as he suspects the structure of the damper material not being OK.

Question

When the new damper felts will be installed should I make sure he also does a new damper REGULATION? I could imagine that,although Renner damper felt is being replaced by Renner damper felt, the thickness may vary a bit, so might the regulation?

schwammerl.

Even if the dimensions of the new felt were perfectly identical to the old, chances are they would not be installed so that no regulation would be required. Some regulation will be required.
I am curious if the dealer is a qualified technician?
Dealing with uneven trichord wedges as you have mentioned is normally done because damping is not efficient - one or more strings leak.
Damper noise like a thump when pedal is released is a different issue.
With the new felt there is a chance that you may have the same problem.

Gene,

Thank you for your reply.

However you make me worry a bit. Yes the noise apperas when the dampers come down - but not only when the pedal is released but also when an individual key is released.

You wil understand if I do not comment openly on the dealer's technical qualifications but what would you have in mind that could cause this phenonemon?

schwammerl.

A long distance diagnosis is a bit like going out on thin ice...
The damper felt may be just fine.
But what may be going on is that the tri-chord dampers need to be trimmed. They are probably extending down below the string plane at rest - correct?

If this is the case, replacing the damper felts and all the regulation may not be adressing the problem at all.

To do this, the dampers need to be removed and carefully trimmed with special shears (scissors) so that they are not capable of exciting the strings on their way up or down.

Some things to consider: very hard dense felt, (usually old and compacted) excessive lift lever return spring tension, lift lever with lead where not required or excessive lead (depends on what part of the piano), possibly the felt types on the damper blocks could be changed - example: if there are wedges front and back the tech may want to experiment with front wedge and rear flat.
Search the Renner web site, they give guidelines for how much resistance at the lift lever there should generally be for the different sections of the piano - with the proper gram gauge your tech could measure the lift lever resistance and compare to see if it is within a normal range.
Sometimes the grain direction of the felt can make a difference.
The felt that I like to use is made by Yamaha for the CF piano but it is not easy to get. It is soft, damps very well and I rarely have problems with excessive return noise but some noise is normal.

Gene, it is a brand spankin new piano. We are talking Estonia, not a 1940s Brambach. Surely the damper system doesn't need to be re-engineered....

Please don't ruin a completely good set of damper felt and the hours of regulation at the factory for no good reason. Dampers will make some noise. It's the nature of the beast. No way getting around this. Some makes will make more than others.
You can lessen this problem to some extent. Gene gave you one solution-trimming. I'll also add that brushing powdered teflon on the felts in addition to trimmimg will further lessen any noise, but you have to take to heart that there will always be some amount of noise caused by the felts and or the whole system. Again, it's the nature of the beast. It's the way the system functions and is designed. Try not to let it be your whole entire focus. Enjoy playing and you will in the end get used to it like every other grand piano owner.

Gurgen, you are right, I forgot that new pianos do not have any issues with installation of parts, they get it right every time.
I think that trimming felt for buzz or leaking string is good but not necessarily a cure for a thump on return.
In either case some experimentation may be necessary.

Gene, there is only one person who mentioned the word thump. and it was not Schwammerl.


Have a Cool Yule.

Thanks Jurgen, I did read "thump" into the thread and appologize for that.
Maybe Schwammerl will describe the noise in a bit more detail.

I have noticed some piano makers seem to set the head so it sets on the front slightly before the back. When the damper sits perfectly flat to the strings, it makes more noise on the return. So if the damper shuts off the note properly, try tilting the head so the rear lifts just before the the front.
My other suggestion would be to check the upstop rail. With use of the sustain pedal and no stop on the pedal, the upstop rail gets jammed. Now there is more room for the head to accelerate. The rebound could be causing excessive noise.

Oh, make sure the noise is not related to the tray returning or the key returning. With the action out, pump the underlevers and the tray by hand

Fine tuning a damper system is something best left to a seasoned pro. There are so many little tricks and techniques that go into a truly well-functioning system. In our area there is only a small handful of technicians who I would trust to be able to do high level damper work.

I too question whether the dealer could be well qualified for this task. Custom work is not the same as warranty work.

High level custom damper work, like high level tuning, voicing and regulating, is a specialty that the average technician probably isn't prepared for.

My advice: You should find the most experienced technician with the best reputation, and pay him well to get the most out of your piano.

Tank you all very much for the comments so far.

I will try to answer some specific questions raised and clarify a few issues.

Ryan,

If already only a small handful techs in the US are capable of doing serious damper regulation work then it is very likely there will only 1 or 2 in my country. Moreover you should know that because no formal education system is in place in Belgium for piano techs, people have either to get experience from working with a dealer or from learning the job in a piano factory in Europe or Japan. As a consequence most qualified techs are employed by dealers and good indepedant techs are almost impossible to find. That is why I already made a contact with a very competent tech in Germany who was recommended to me; he suggested to first try to solve as many issues as possible through the dealer as many those I mentioned were warranty issues in his opinion. Calling in a tech from Germany would be a costly matter as well because for e.g. 3 - 4 hrs work at my home I would have to pay him 6 hrs travelling (3 hrs way and 3 hrs back).
By posting this question on this forum I merely intend to acquire enough insight as to judge whether or not suggestions put forward by any tech here make sence.

Gene and Jurgen,

About the expression "thump".
You are both really challenging me here as piano sounds are already difficult to describe in words and on top of that I am not an English native.

I would say it is a sizzly thunp whenever one of those tricord dampers come down on the string. It is as like the damper does not shut off the string fast enough; when you help the the damper a bit coming down on the string somewhat faster/harder, you don't have that noise - just an observation.

curry,

If it would be simply "the nature of the beast" I would be extremely disappointed with this new instrument. This 'sizzly thump' is not the 'zing' one almost always hears when when pressing or releasing the sustain pedal; the noise that is produced when reasing a single key during e.g. staccattto or portato playing is really distracting and the tone is altered much.

Jurgen,

Yes, the tricord dampers do extend slightly below the string plane but at least on operating a key you cannot see the tips would touch/excite the strings; again it is not the traditional 'zinging' sound I am talking about.
In the picture below the dampers are raised unfortunately:



schwammerl.

As Ryan mentioned: a good damper job needs an excelent technician and there are not so many of them. I got that (usualy good) formal German training and might perhaps be better prepared than a Belgium tech, but even I don´t feel competent enough to solve a problem like that

But I have a competely different suspicion and I think it´s not a problem of the propper setting of the felts. I assume that it has to do with the mechanism of the middle pedal (btw: what it´s name?). I had the same problem with an Ibach grand from 1970 or so a few weeks ago. I will try to explain it without using the propper terms because I don´t know the English terms. I even don´t know the propper German terms

There is a rod that will be lifted when you press the middle pedal. When lifted, that rod keeps the dampers of pressed keys up. The damper flanges (?) have a "nose" that will be kept up by that rod. The problem might be that these "noses" touch the rod even when the pedal is not pressed and therefore the rod is not lifted. I.e. the flange with the nose falls down when you release the key and the nose touches the not lifted rod and produces that strange sound.

Schwammerl, do you feel able to remove the action out of your grand? If so, do it, but be carefull!!. Then take a look at these "noses" and the rod. Lift an affected damper by hand and let it fall down while you are looking at the nose of that damper. If it touches the rod then you found the problem.

On that mentioned Ibach i was looking around and around and couldn´t find the problem at first. I started with needling the damper felts because I assumed that the felts were too hard. After all I was really surprised when I found the solution. The reason was that the rod was deformed / bended. That should not happen with a brand new piano, but who knows? Perhaps the rod is just not propperly installed.

I hope you can understand what I wrote so long winded in poor English, I am no native speaker, too

Gregor

Ah, for that sound, changing the damper felts might work. Trim the felts so they do not hang below the strings. A good pair of moustache sissors is what to use. You can see the string mark on the felt. Trim any excess that is not being touched. Do this before you try changing felts.

A slightly sluggish damper flange can contribute to that problem also.

The noise usually created by damper wedges hanging below the strings is a whispery sound what many techs call "whooshing". Its caused by the dampers lightly strumming the strings when they lift off the strings.

schwammerl's complaint was when the dampers were coming down, so I doubt that trimming is going to solve his problem.

I think that "zinging" would be due to some harmonics leaking through because of uneven pressure on the strings. If you pluck each string individually you can usually hear if one is not damping well.

In Steve Brady's new book "Under The Lid" he has a section by concert tech Linda Smith about how to reduce damper "oinking". That is another word to describe poor damping on key release - especially on slow key release. It can be very noticeable and annoying. One thing she suggests is massaging the trichord wedges with a capstan tool. You can use the bent end to get in between the legs of the felt and spread them out a little bit while also loosening up the surface.

Steve's book is excellent by the way. A must read.

Ryan,

One could not describe the damper problem better as you did with the word oinking as opposed to whooshing which is indeed a totally different damper problem; a word certainly to take up in our piano vocabulary.

Would you spell the word 'oinking' phonetically you will here almost exactly what disturbs me.

schwammerl.

Schwammerl, we techs have a whole set of terms (I hesitate to call all of them "technical terms") with which we try to describe and differentiate sounds, regulation and voicing steps etc. Mostly, these are of little interest or use to players and piano owners.

Schwammerl,

The new felts should eliminate the problem if installed carefully. It is not possible to install new felts without regulating the dampers, so the answer to your original question is yes, the dampers will be regulated.