Piano World Home Page Forums Our Most Popular Forums Piano Tuner-Technicians Forum Buzzing sound and damper regulation.

Hello everyone.

A couple questions arose while servicing my piano for which I couldn't find the answer I was looking for on the internet.

There is a buzzing sound in a 1964 Rösler, when playing F3, F#3 and G3. It is coming from a piece of wood layer about 1 cm thick and it is separated from the 2 cm thick wood layer under it by a gap of about half a centimeter. Under the 2 cm layer is another layer that starts from the upper left corner and runs under the two other layers. The piece that buzzes, viewed from the front of the piano, starts from the center of the leftmost area behind the strings and runs diagonally to the center uppermost side. It covers the rest of the rightside of the area behind the strings. So I'm guessing it is the uppermost layer of the soundboard? The piece that buzzes is separated from the rest of the uppermost layer by a thin crack, the separated part is about 15 cm wide.

My question is, how is the uppermost layer of the soundboard attached to the layer beneath it? If I press moderately on the buzzing piece of the uppermost layer, the buzzing stops. I'm thinking the uppermost layer should be attached to the layer beneath it and if I could somehow attach them together even lightly with a glue of some sort or a screw, it wouldn't buzz anymore. How should I approach this problem? There are many other cracks in the soundboard, but they aren't problematic.

Another question I have is about damper regulation. There are screws on the dampers to adjust when the sustain pedal lifts the dampers. Since the screws regulate when they lift with the pedal, does it matter whether I regulate the moment when the damper rises when pressing the key by bending the damper wire or the damper spoon? If I bend the wire to make the damper lift later when pressing a key and then turn the screw to make it lift at the same time with the other dampers when the pedal lifts them, is it any different from bending the spoon?

I am a beginner and perhaps I am slightly overthinking this. Any insight is welcomed.

Forgive me for being blunt here-
But, you'll probably regret it in the end if you try to do this stuff without experience... DIY is fine for certain jobs, but you're getting rather technical with the things you are mentioning...
If you mess-up the damper regulation (yes there is a difference in adjusting the spoons compared to the wires)- it can get real ugly.
I don't mean to discourage you (well, yes I do actually LOL), but a tech would be a good person to call on here- believe me, I'm not just saying this because I am one- but for your own sake...
You can learn from him/her while they do the job right- if you watch and ask lots of questions.

Now- IF you are not afraid- and don't care about possible consequences--- get a book on Piano Rebuilding, this will give you just about all the info you are looking for (section with soundboard repair, and regulating).

Hi partistic.

There are too many "layers" and "gaps" in your description for me to to understand what you may be talking about. But then, I only have 29 years' in the field.

Did you find a mentor yet as I had recommended some time ago?

One more thing - Christmas is a good time to have someone give you a book on piano technology if it is too expensive for you to buy yourself. Once you can name piano parts, it will be a lot easier to communicate with others.

Agreed Supply-
I was lucky enough to be able to apprentice back in the 90's under a couple of pro's... The first thing the rebuilder did was to set a chart down in front of me with a diagram and the part names...He told me to memorize their names and then we would continue.
You have to learn the language- just like with computers, or many many other things.

Thank you for your answers.

I would love to find myself a mentor and work for free after my schoolday as an apprentice with a piano tuner and restorer, if I could only find the chance. I love working on things myself, especially all sorts of mechanical things.

I have acquired myself the Reblitz book. I have not read it through cover to cover, but the best I can read the relevant parts, I cannot find any information about two layers of boards covering most of the soundboard (? I think it is the soundboard ?). I would very much appreciate if anyone could give me a good diagram. I couldn't find any screws that hold the uppermost layer tight against it's lower layer, so I'm thinking it is glued. Since I probably can't glue it back together without unstringing the piano, I'm thinking I should just wedge something between the keybed and the board, since moderate pressing against it stops the buzzing completely.

If anyone could give me the name of the board that is loose so I can do search the book or the internet on fixing it, I would highly appreciate it.

I made a couple of picture to illustrate what I am talking about.



The edge of the board that is loose is marked with the arrow. It covers the rest of the soundboard on the right, as far as I can see.





There are some sort of holes in the board beneath the loose one, which look like they might have some sort of a screw in it, but there doesn't seem to be any. Nor is there a screw head on the backside of the piano. There are also some higher round parts on the loose board, which look like they would fit in the holes.

Hello everybody.

I lodged some sort of a book between the unknown board covering the soundboard (or is it THE soundboard?) and the metal plate which has the strings. The buzzing stopped, but it seems the piano is a little bit more quiet. I guess the lodged book is stopping the board from vibrating.

So I'm not sure if the book is a good long term solution. All I would like to know is what is that mysterious board and how should I reattach it. I was thinking about slaughtering some PVA glue in the crack and pressing on it until it dries. Is that a good idea?

Another problem I encountered, the dampers on the lowest bass wires that dampen only one string are so wide they rub against each other. Should I knife them?

All I want is the piano to be in a reasonably playable condition. It was 2-3 semitones flat, hammers let off at half the striking distance, dampers started moving immediately etc. Now it is miles better, I just want to fix the buzzing. It is in tune, I did some voicing and regulating. The buzzing is the only problem. Please I would appreciate any suggestion.

The actual repairs are pretty straightforward. I know what I would do, but would I give the procedure on a public forum right out there for God, the public, and lawyers to see? Not on your life! One lawsuit by a DIYer many years ago cured me of that bit of foolishness.

The advice to hire a tech is not self-serving. It comes from years of cleaning up messes made by owners.

Doesn’t matter really what that board is; just use a wedge and some yellow carpenter’s glue and re-attach it where it appears to have broken free. Use the book or some other type of wedge to push the pieces together…. The book was touching the plate and the sound board at the same time; this is why the muted sound.

Well put

There seems to be no holding you back. Go ahead, knife them [sic].

Just make sure that the glove doesn't fit, that way they have to acquit. ...sorry, I just had to do it

No Kidding David? Wow! And, they wonder why we are Leary of giving advice over the internet!

Personally I GREATLY appreciate any wisdom that a skilled technician (in any trade) ever gives me. Would I sue someone because I undertake a task myself and screw it up? Certainly not, and that's a terrible shame. Please don't stop sharing knowledge. I often do this myself in other things (computers and audio tech) and it brings great pleasure.

I'd never touch a nice piano. I too have an old piano which I got when I suddenly had much more time on my hands. It has a couple of small issues (it buzzes, hence reading this thread, but mainly just on middle C) but they don't bother me too much as to start messing. It may well not be worth the effort (not sure it holds tune yet), but all the keys play reasonably. The main thing is that I enjoy it.

Partistic, the only advice I can offer is to tackle each problem one at a time, and go very slowly. I can't imagine that the rubbing dampers are such an issue, unless they stick completely. If they do, then maybe very light filing of the sides may resolve the issue - and of course only one side of each damper may do it. Only do the ones that need it, but i think fix your buzzing issues *first* because how often do the lower keys ever get played? Prioritise. Less risk, most gain.

Go slowly and never ever commit to cutting, glueing or cleaning anything you are unsure of.

I hope the language barrier is not too much of a problem.

Happy Holidays and a successful New Year to all.

I cut the dampers repeatedly with various knives and scissors, they wont be causing me problems anymore. They offered some resistance, as the dampers were relatively hard and had some sort of a strong thick layer on it. I don't know, perhaps some previous technician lacquered the dampers before.

I filed and poked with needles all the dampers with two or less strings to get rid of the thick thin hard layer stuff and the dampers work much better now. Previously I had many problems trying to get the dampers damp properly, because the contact area didn't have soft felt, but some sort of hard stuff.

The very low keys needed twice the weight to press them down, it was around 130 g when I measured them. Pretty heavy. Now they are alright, still heavier than others but within reason at least.

Tomorrow I will get some glue from the construction shop and dump it in the crack.

Thank you all for the advice and suggestions!

I glued it back together. Now there is no buzzing. It is great. I used a drinking straw to pour the glue through the strings to the crack.

The piano is now decent. Dampers are good too after knifing. Thank you all for the advice and encouraging words.

There is no reason to be afraid of giving advice. You guys shouldn't worry too much, people are good and nice, they have good hearts. I'm going to do my best anyway. It would be very ridiculous and shameful of me to sue someone for my own stupidity if I screw something up, and no court would ever take it seriously.

I mean, if my friend gives me a drink and I die because of choking on it, it would be ridiculous if he would get sued later.