Tuning

Tuning influences

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Gigio85

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Opening post by Gigio85

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Genova

Good evening everyone and happy holidays given the period =D First of all, compliments to those who manage and are behind this spectacular site, between videos, forums and so on, you are number one.. getting to the point, I wanted to ask for clarification on something that seems insignificant to me, but I have already heard more than once.. I have been told that before tuning, it is important to check the position of the casters on the 3 legs of the piano which must be at a certain angle, this also referring to acoustics and normal use.. is it possible that something changes, in the sound or in the tuning, just because the leg casters are straight rather than perpendicular to the length of the piano? and eventually what other things influence sound, and consequently tuning? I hope I have written this in the right place, don't shoot me if not! =D Good evening to all, waiting for zampone and lentils! =D

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Reply 2 by Thesimon

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Ariccia, RM

Thank you for the holiday wishes, which I reciprocate, and for the site, welcome!

I confess I have never heard of such a thing. Strictly speaking, physically, nothing should change. The piano legs are firmly anchored to the case, therefore I do not believe it is affected by flexions if the ground contact point changes by something in the order of a centimeter. What I feel like saying is that the floor resonances, transmitted through the piano legs, certainly change by a few Hz, because varying the distance between the ground contact points varies the wavelengths of the resonances and thus their frequency. But in such a case, if one were to "notice" it, so to speak, it would be more the neighbor on the floor below than you, who plays and experiences the direct sound and all the reflections of the environment. Let's see if there is anyone else who has had direct experience, but honestly I believe that nothing changes...

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Reply 3 by Gigio85

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Genova

Ahahah ok and thanks for the answer.=D downstairs there is a deaf old lady, I would say it doesn't change much for her if a few Hz get lost in the walls =D in any case, regarding the leveling feet at the bottom of the legs, as far as you know, do they have to be in a certain position/angle or can they be haphazardly placed as the piano has been moved? I also mean in terms of weight distribution/stability or other factors.. even to me when they said it seemed like nonsense, but since nothing is left to chance in a piano I preferred to ask you who are experts in the field, since I have heard it from + people..

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Reply 4 by Andry

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Roma

well generally you check that all the wheels weigh on the floor/caster cups, especially in baby grand and parlor grand pianos which will probably have more weight on the upper part of the keyboard where there is more cast iron, but basically we are talking more about safety since the weight of a piano is in the hundreds of kg depending on the era and materials; we are easily around 300-500kg, so it is more than anything good practice to ensure that the weight is distributed across the legs as uniformly as possible

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Reply 5 by Fra

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A grand piano rests on three legs, making it impossible to have weight distribution problems; furthermore, no floor is perfectly flat or level.

A vertical piano is more prone to resting on 3 wheels; this is not good and one must ensure it is leveled somehow, not because it causes problems to the structure, but to prevent it from moving. The string tension is loaded onto the pillars at the back, certainly not onto the floor.

There are some uprights, more or less old, that rest on three wheels not due to serious flooring defects, but because over time they suffered a frame deflection due to unbalanced load distribution. An example was/is the Anelli model 30, which did not have a continuous brace on the bass section. The frame tended to flex forward on the bass part, and all those models ended up resting on 3 wheels. Even tuning them to unison was risky.

However, honestly, saying that tuning is influenced by positioning the piano perfectly level is a bit excessive. Rather, keep the humidity constant, as its variations alter the crown of the soundboard, causing the tuning to rise/fall on the central part of the plate with differences of even 2/3 Hz.

The longer the piano, the less it is affected by these variations, also in relation to the tension of the plate which depends on the design; plates with higher tension compared to the normal 70/80 kg per string are more sensitive to small climatic variations.

For example, old Ibachs had a central A that was 44 cm long instead of 40 cm; tuning it to unison is like taking, for instance, a G4 from a Steinway and stretching it until it sounds like an A4.

Here, very often people talk about tuning stability, stability, etc., in relation to the environment and the positioning of the instrument, which is certainly very important, but no one ever stops to discuss construction or design aspects regarding the type of plate, frame, lengths, thicknesses, etc..... I haven't understood if the subject is not of interest or if knowledge is actually scarce and it is more convenient to discuss the weight pressing on the leg....

In short, every piano is its own history.

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Reply 6 by Gigio85

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Genova

I wouldn't be able to tell you, but I can suppose that it's not that it's not of interest, but probably on the construction side, it is already taken for granted that pianos are built based on accurate calculations that change from house to house and are therefore not very debatable, while one focuses on external factors, such as the environment and the position of the instrument, which are more understandable and upon which one can intervene more; in the sense, if I know that I am playing in a cave rather than in the desert, I expect that the tuning won't hold, whereas if I know that the strings are of that diameter, that they have that certain load tension, etc., there is little I can do, unless I want to overhaul the piano by changing strings, etc.. =D anyway mine was just a curiosity, heard from others and which didn't seem very credible to me; it never would have occurred to me to think that the wheels could have any effect on the plate, that's why I asked.. and I see that I asked in the right place! Thanks for the answer =D you are always the best. =D

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Reply 7 by Andry

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Roma

certainly these details are not discussed due to a lack of knowledge, and also the fact that nowadays one only finds Yamaha, Kawai, or tuned Steinway around (obviously I am exaggerating to emphasize the point...) which are the best-selling brands to pianists studying at conservatories or piano teachers.

p.s. if you want to split hairs, dear friend, what you say is correct, but keep in mind that it is NOT impossible for a leg not to rest (partly because there are pianos with double legs, so 2 per side), then as in my case you could have an old piano that has the brass wheels inserted into the wood and screwed in (half a centimeter or less is enough and one of the two paired wheels does not touch), third but, in effect, improbable case: the legs have been replaced

it's just to talk; it is obvious that the question itself deserved a blunt answer: no, the direction of the wheels does not influence tuning, however, wanting to be imaginative, I reported my experience

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Reply 8 by Fra

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We are talking about nonsense; if it were as you say, by putting a piano on its side or simply transporting it, a disaster would occur.

I have had many pianos in my house, uprights and grands of various brands. I have also seen several, tuned, disassembled, wrecked, but we probably have had different experiences. I also know several technicians, some with over half a century of experience, and major dealers in the sector, but no one has ever maintained what you are saying.

Now, one can certainly hold their own ideas even if they are fanciful, we read them, but do not say that I am wrong to write, bringing up pianos with double legs

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Reply 9 by Gigio85

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Genova

I also imagined that "no" was the answer, and I repeat, since I heard this from different people, and I don't think they agreed with each other, I wanted to know if you had ever heard anything like it, since it seemed like total nonsense to me.. and if you knew anything about it.. maybe they meant more than just tuning, saying that it influences the sound, but even there we are, as Fra says, talking nonsense.. surely a wheel turned at 45 instead of 90 degrees won't transform the sound.. on the other hand, I had some slight vibrations a while ago, which were canceled out by slightly changing the position of the wheels.. maybe it's a coincidence of things and the wheel has nothing to do with it, but that's how it went..=D thanks anyway for the answer!

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Reply 10 by Bianca

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Torino

By rotating the piano's caster wheels, the resulting "moments" induced on the piano case can change (since the wheels are not aligned with the legs). Because of this, the "vibrations" may vary. For the rest, it seems irrelevant to me....

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Reply 11 by Bianca

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Bianca wrote:

By rotating the piano's caster wheels, the resulting "moments" induced on the piano case can change (since the wheels are not aligned with the legs). Because of this, the "vibrations" may vary. For the rest, it seems irrelevant to me....

In fact, strictly speaking, even the tuning could change, since by changing the moments, the lengths of the strings change (imagine a more or less tense bow), but to understand by how much, precise calculations would need to be made for each type of instrument, and the result might still continue to be irrelevant.

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Reply 12 by Thesimon

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Ariccia, RM

The moment of what? This reasoning is not clear to me... Are you referring to torque? The lengths of the strings do not depend on how the pulleys are positioned; they depend on the distance between the nut and the rear anchor point. We are always talking about a rigid instrument, reinforced among other things by a robust cast-iron frame. By varying the distance of the support points by a few centimeters, I believe at most 2 cm, due to the rotation of the pulleys, it is difficult for me to think that it would even significantly affect the tuning... So, strictly speaking...

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Reply 13 by Bianca

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Torino
TheSimon wrote:

The moment of what? This reasoning is not clear to me... Are you referring to the torque? The lengths of the strings do not depend on how the casters are positioned; they depend on the distance between the nut and the rear anchor point. We are always talking about a rigid instrument, reinforced among other things by a robust cast-iron frame. By varying the distance of the support points by a few centimeters, I believe at most 2 cm, due to the rotation of the casters, it is difficult for me to think that it would even significantly affect the tuning... So, strictly speaking...

the bending moment. The leg rests on a caster that is not aligned with it (but is eccentric by a couple of centimeters). I also think it is insignificant, though...

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Reply 14 by Bianca

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Bianca wrote:

bending moment. The leg rests on a caster that is not aligned with it (but eccentric by a couple of centimeters). I also think it's insignificant, though...

since I can't make a drawing it's hard, but imagine that instead of legs there were L-shapes with casters at the bottom...

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Reply 15 by Bianca

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Torino
Bianca wrote:

since I can't make a drawing it's hard, but imagine that instead of legs there were L-shapes with wheels at the bottom...

anyway it's "nonsense" (aside from the vibration which could be a factor, I think), I challenge anyone to notice the difference by ear.

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Reply 16 by Bianca

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Bianca wrote:

since I can't make a drawing it's hard, but imagine that instead of legs there were L-shapes with wheels at the bottom...

also the case is not "resting" on the legs, but is configured as an "interlock"...

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Reply 17 by Gigio85

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Genova

I agree completely, you must have an alien ear to hear differences..and I'm already lucky if I hear the beats =D

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Reply 18 by Fra

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266

My guys, the notions of piano mechanics are interesting, but the concept applied to the piano soundboard caused by a tilted caster is pure delirium, almost like something from a physics student

Speaking of tuning, the tension of the strings exerted on the frame is not discharged on the [soundboard] but on the capos along the ribs and especially on the wedge located under the frame intersection.

The legs, unscrewed casters, or a slight slope in the floor have zero influence on the stability of the tuning

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Reply 19 by Fra

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Bianca wrote:

inoltre la cassa non è "appoggiata" sulle gambe, ma si configura come un "incastro"...

Such a tiny arm though, let's not even go there....

The legs slot into the cabinet and sometimes the pianos wobble; when these slots loosen, especially on the last leg that is assembled, where the movers deliver hallucinatory blows.

Other models, Kawai for example, have screws so that the leg becomes integral to the cabinet.

In any case, the weight of the piano rests on the legs; you cannot consider it merely as a slot/interlock mechanism

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Reply 20 by Bianca

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Torino
Fra wrote:

Such a tiny arm, but let's not go there....

The legs get stuck on the cabinet and the pianos sometimes wobble; when these fits loosen, especially on the last leg that is assembled, where the movers deliver hallucinatory blows.

Other models, Kawai for example, have screws so that the leg becomes integral to the cabinet.

In any case, the weight of the piano rests on the legs; you cannot consider it just as a fit

but of course, I was only trying to give an idea of why such an assumption would be made.

Anyway, precisely because the leg is integral to the cabinet, it is said to be a fit (and as such must be studied in statics) and not a simple support

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