Tuning

Flattened felts with string marks

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maquieto

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Opening post by maquieto

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Hi Paolo.. I've had this problem for a while now... the sound of the piano (Yamaha U3) turns out to be a bit flat... so to speak.

I would like to have the hammers refurbished or the felts shaved, but shaving had already been done some time ago...

At the moment I don't have the possibility to get to work on it... is a DIY remedy possible?

I remember years ago I took a pin and tried to regenerate the felt bit by bit... the effect wasn't great but... it lasted very little.

If you have any advice..

Thanks a lot.

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Reply 2 by pianoexpert

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Shaving a hammer head is not easy. Many technicians also make mistakes. One must also see to what extent the hammer head is worn, because if it is deeply grooved, a lot of felt must be removed to restore the correct shape. Furthermore, by shaving, the geometry of the action, the striking point, and the key weight change. If it must be replaced, a hammer head suitable for that model must be ordered, and the shanks must also be replaced. The old hammer head must ABSOLUTELY be preserved exactly as it is mounted. That is, it is very important. The sound of the new hammer head will also depend on proper voicing, and it will be necessary to check the keyboard balance, maintaining the same let-off and repetition points. The hammers must have the same radius and taper. Therefore, replacing hammers is also a job for experts.

The "pin" system has indeed softened the apex a little, and at the moment, the sound has turned out sweeter, but you still cannot transform a hammer head designed to have a fairly bright sound into one with an "extremely sweet" sound. One must strive not to distort the inherent structure of the hammer head itself.

Lastly, it may be that it is not yet necessary to shave or replace, but rather to perform good regulation along with tuning and voicing.

Let me know

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Reply 3 by maquieto

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Actually true... I wanted to put in a RENNER but they recommended other hammers that have softer felts.

In the meantime, I'll have it tuned now and then we'll see.

Thank you

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Reply 4 by pianoexpert

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Renner hammers are excellent. A very well-compressed hammer allows for good tuning and a good dynamic range.

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Reply 5 by pianoexpert

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I hadn't read carefully that the hammer has already been shaved. There is no even talk of a second shaving.!!!!

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Reply 6 by maquieto

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Indeed .....the sound is really down by now...flat flat and you almost have to give momentum on the forte to make the notes sing, otherwise you can't...I don't know if you heard the German [recording] I posted ...maybe from there the sound is barely audible..but...I don't like it.

For this reason, my tuner advised me to change the hammer rail (martelliera).

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Reply 7 by HansElzinga

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With Yamaha pianos, another possibility would be to disconnect the bass strings one by one, do a rotation, and then reconnect them. This will change the sound from flat to bright. However, you must be careful to rotate in the right direction, i.e., in the same direction as the coating.

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Reply 8 by maquieto

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if I haven't understood correctly... detaching the strings from the pins while remembering the assembly direction (high/low) and then putting them back in place.. This would practically relieve the pressure and the load on the cast iron? I am also waiting for Paolo's comment. Unfortunately, I know nothing about adjustments.

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Reply 9 by HansElzinga

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Loosen the string tension with the key. Keep the upper part of the string tied where it is fixed to the ankle and detach the pin at the bottom of the string loop using pliers. Be careful not to let the string slip from the pliers. This is not easy because there is tension and the string wants to return to its old shape. Holding the loop with the pliers, turn it once or twice (in the direction of the copper winding) and then tie the loop back to the pin. Once tied, tune the string with the key to the correct pitch. Then do the same with the next string, etc.

In this way, the (copper) winding of the string becomes tighter around the inside (iron), and then the sound will become bright again.

Let me know if you didn't understand everything and excuse my slightly broken Italian

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Reply 10 by maquieto

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Of course... perfectly clear..

What nationality are you?

I understand... you are saying that over time the string (or rather the copper coil that forms the string) loosens in its tension and therefore by giving it another turn you go to do something like a new winding, returning the string to its initial tension... the sound thus returns to tension and therefore becomes bright and less tired..

I would never know how to do it myself but I would say that it could work.

You have already done this on some pianos? Do you work in the sector?

Thanks, anyway.

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Reply 11 by HansElzinga

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You understood correctly. And yes, it would be a job for a technician. I am Dutch and in June I will be in Italy to do piano work, first in the Turin area and then in Acquapendente.

If I understood correctly, are they the low strings with a flat sound? Normally iron strings remain bright for longer.

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Reply 13 by pianoexpert

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The Dutch friend, inhabitant of a beautiful and dreamy country, says it well. But I would wait before doing this. Strings are turned when they are very dull, because the copper has lost some grip. So by turning them half a turn or even a full turn clockwise (only Steinway counter-clockwise), the copper comes closer to the steel. But I would wait. Replacing the hammer felt is the right thing to do, as well as the pins, taking care to keep the old hammer felt intact to be returned.... It is extremely important !!!!!! Same shape, same weight, same impregnation and "diamond" shape, especially in the high notes. Keyboard rebalancing check and preventive check of the center pins of the bridge notches and the escapement uprights. An accurate voicing after impregnation, to be performed carefully on the instrument after tuning. Proper regulation is also important, respecting the specifications dictated by the Manufacturer

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Reply 14 by maquieto

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Yes, yes indeed.. at the moment I'm not doing anything, also because I wouldn't know how to do it.

In what sense are you talking about the hammer mechanism to be returned..

Are you speaking for a comparison with the new one (setup, measurements) or some other reason?

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Reply 15 by pianoexpert

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Exactly. The original hammer action is part of the piano's identity, and if something goes wrong, the new one must be compared with the original one.

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Reply 16 by maquieto

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I find it a very intelligent thing.. I would say.. in fact, even the piano in all its components undergoes a general transformation as it is played. I don't remember if it was in this post, but it is seriously true that the piano sounds according to how it is played, right?

The voice changes depending on how the keys are pressed and everything modifies itself.

If something were wrong with the new hammer mechanism, it would be difficult to understand why without a reference.

Great thing.

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Reply 17 by HansElzinga

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Maestro Paolo, I wanted to ask you, why also replace the pins? Isn't it enough to just change the hammers? Normally I do this.....

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Reply 18 by maquieto

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Surely, even when playing, the wippens also deform based on the notes struck most frequently, and therefore, mounting new hammers on different wippens might result in an unevenness of the level line (at an optical level).

I believe that is the case. Let's hear what Paolo says.

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Reply 19 by giovannig

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The felt dampers dry out over time, so to restore the proper elasticity, it is good to change them when replacing the hammer rail. This provides the advantage of keeping the old glued hammer rail as a permanent reference. In my opinion, the savings on materials do not compensate for the hours of work spent ungluing the hammers, replacing the rollers (if the hammers are worn, the rollers will be too), and remaking the pins if necessary...

I don't know if Paolo thinks like me...

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Reply 20 by giovannig

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Steingraeber today, to achieve greater elasticity, even installs bamboo pins. The elastic impact of the hammer on the strings is extremely important to produce a clean and powerful sound, minimizing energy dissipation that can lead to a perception of "fatigue" on the keyboard, along with incorrect felt elasticity in relation to the string plate (hammer choice).

Other elements that introduce dissipation, besides the frictions well known to everyone, are for example the key bushings, the center roses, and the number of paper shims used to level and ensure the keyboard breaks in uniformly. As well as the strings themselves.

The state of freshness of all these components certainly improves the positive perception of our instrument, details that are often neglected during a restoration due to mindset rather than economic reasons.

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