Piano World Home Page Forums Our Most Popular Forums Piano Forum Can a Pianist's Touch Alter Tone? A Scientific Study to Refute The Myth

This isn't entirely clear....velocity is essentially the speed of the hammer swinging at the strings. Weight is one method of moving your fingers to get the hammer to that speed.


Yeah, that's the benefit of thinking in terms of weight, it gives you evenness between multiple notes.

Maybe it is not a myth. See here , the results of a purely mathematical simulation that indicate that touch affects the partials distributio. A close let off distance is needed for that results.


So by pure maths, it is demonstrated that the effects of the flexible shank can explain the pianistic touch, even without considering the predicted horizontal hammer rubbing. A well regulated action is determinant, as some flex in the shank. Maybe this is why high quality pianos are more expressive.

The piano is a mechanical device more complex than a mere hammer thrown in the air. Pianistic touch can be a discipline to control velocity, and also the flex of the shanks.

Are WNG carbon fiber shanks too stiff to flex, so less expressive?

And there, my friends, is the answer. Any questions?

Well, when you put it like that, it seems so obvious now...

When other factors are taken into account, the thing gets complicated. At the bottom of page 10 begins the results discussion, or just observe the figures and forget the pretty equations.

For myth believers, this is science supporting you.

Look at the difference that results when using double precision numerical representations compared with multiple precision:


That's a result of the high number of calculations used in the simulations.

You can look for yourself:



Edit: to me the shanks look about the same as regards to flex.

I selected my action to maximize performance and minimize maintenance. Longevity was another important factor to me. WN&G states on their website they designed their epoxy carbon fiber shanks based on ideal wood shanks, and their design also provides consistency in strength, flexibility and weight. I selected WN&G shanks because they met my criteria, and I love how they perform. I realize that wooden shanks can be selectively shaved to adjust flexibility and further optimize performance.

Greetings,
It's always interesting to make these comparisons, however, their validity has to be questioned. Regardless of what perceived manipulation a wooden shank offers, there is no way to get 88 of them the same, so drawing comparisons between WNG parts, which are identical at any sane level of measurement, with "wooden" parts means comparing a standardized component to a variable one. AND, even if you did manage to get 88 shanks to behave exactly alike, as soon as the temperature and humidity change, all that will change, too.

If a pianist is good enough to control the tone with flex in the hammershank, they will love the WNG parts because they all offer the same mechanism to control. If an artist is saying they can better control an inconsistent set of wooden action parts, I will have to see it to believe it. The pros I have replaced actions for, with WNG parts, all say the same thing, "I've never played one this even before".

That is in addition to the pinning, which on a wooden shank with felt bushings will need approx. 20 grams of resistance to match the stability of a WNG shank with 1 gram. An action with 20 grams friction will not play. I can reduce the friction of shanks and whippens so much that noticeably more of the pianist's effort is focussed on moving the mass of the hammer, not overcoming drag in the action.

I have never seen an audience of piano techs that could tell the difference in sound of a note played by various means, ( and, we have tried). If the amplitude, which is dependent on the speed of the hammer, is the same, the note sounds the same.

Regards,

So, I've read the paper several times now, looking for a way I can use this to improve my playing (I'm always looking for new ways to make sounds at the piano).

Here is the difference they found (one from a simulated legato note played FF, one from a simulated staccato note played FF, and the black line is a model they discarded as inaccurate). The notes are roughly the same volume, and the hammer hits the string with roughly the same velocity.



Overall the two graphs are notable for their similarity. The one exception is so striking an outlier that it seems to be a computer error, probably an integration error between their model and that of Chabassier, Chaigne and Joly. This is a common programming mistake, enough so that their are entire theories designed around trying to avoid them (but no known way works: integration errors are still serious).

Math can be used to elucidate or obfuscate. I don't think there's much here. It's notable that they were only able to find an effect when the note was played FF. Maybe I'm missing something here, but I don't see any way this can be used to play different effects on a single note with the same volume. Please correct me if I'm wrong.

That's right. The obvious differences between stacatto and legato notes were timing and the power spectra at close let off (1.5 mm fig 8). The authors imply the resultant sounds are distinguishable. There must be a whole range of subtle variations between the authors' extremes of stacatto and legato for the pianist to explore.

Yes, let's discuss that section.

The biggest problem with this section is they don't mention with what force the hammer hits the string. This is a problem because it is well known that when the hammer hits the string with a different force, a different volume and different color results. This is something that can reproduced by any pianist. The paper says they normalized the graph (though it doesn't say over what variable), and uses weasel words like 'qualitative' and 'crude modeling of reality.'

Because of these problems, the paper would not have passed peer review if this were the only section. Fortunately, it's not.

A less serious IMHO problem is the poor presentation. It's hard to understand the data when it's spanned across four graphs like that. For your viewing convenience, I joined two of them into a single graph:



Finally, I've read thousands of pages of literature on piano technique, and I can't recall anyone suggesting to only press the key part-way down. I've heard the opposite advice plenty, to keep pushing after the key has been completely depressed, but I've never heard anyone say to let go before the key has hit the bed. I think it would be hard to keep an even tone playing that way, but there is a lot I don't know . Has anyone heard of this technique, or taught it, or learned it, or especially know where it originated?

Exactly, that force is determinant. You have previously copy the force graph on a previous post, the data is there. The key press velocity is fixed to 3.41 m/s, and because of the shank flex, the hammer-string interaction force is different with distinct let-off distances or touch, as shown on the graph.



I don't think this paper has poor presentation, but that they focus on calculus methods, not on illustrating what we are discussing. Nevertheless I think that they show that thinking only in terms of hammer velocity and mass is a simplification, and that maybe shank flex is important. Another thing is that let-off distance have to be very close to see the difference.

You have joined to graphs, comparing legato touch with 1.5mm (blue) and 3.0mm (green), why not 1.5mm with respect staccato touch?

My upright has 1.5cm let-off distance , so maybe this is why I can't hear any difference (only the randomness of my bad technique). Maybe the natural randomness of human touch masks the difference on most cases, maybe bad regulation, hammer voicing, or maybe is simply imperceptible always. But now, I would not say that because of energy = velocity * mass and the pianist only controls (hopefully) the velocity ... and so on. Things could be more complicated.

I think, the paper is rather good, I have any reason for thinking that they have coded badly their algorithms, and with the maths expertise they show I suspect that this is not the case. This is a paper of a Maths department, not of a piano techniques', so the presentation is targeted at that.

The paper is a theoretical experiment, with shank flex, but without others factors. They have not yet included the possibility of a pianistic touch precursor coming from the horizontal hammer rubbing with the strings, that would add up the key shock noise. On the other hand they recognize a lack of a better model for the roller felt, or a better touch force modelling.

Mainly because I'm lazy; and because staccato was dealt with more ably in the previous section of the paper.