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#2295057 - 06/25/14 10:16 PM Re: Why and why not adding lead weight to key [Re: Weiyan]
Paul678 Online   content
500 Post Club Member

Registered: 11/13/13
Posts: 628
Interesting discussion, even if some of it is out of my
experience.

Does Yamaha add lots of lead weight into their piano keys?

It sure feels like it. It makes my already weak trills even
more challenging.

I prefer the easier trilling on the M&H that I just tried again.

But would it be better to get a Yamaha, because the heavier action
exercises the fingers more? And makes them stronger?

This way, if I get used to the heavier action, when I move to play
a lighter action piano, I will trill even faster! Like playing
basketball with lead weights on your ankles, and then taking them
off for the big game.

Or would it be better to just get the lighter action that suits
my current technique?

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#2295069 - 06/25/14 10:45 PM Re: Why and why not adding lead weight to key [Re: Paul678]
Ed McMorrow, RPT Offline
2000 Post Club Member

Registered: 12/09/12
Posts: 2117
Loc: Seattle, WA USA
Paul687,
There are actions that have such a level of inertia to them that they can injure some pianist when they try to play challenging pieces. It is very easy to overdo the "heavy practice piano syndrome".

In general Yamaha grands are in the higher side of inertia but broad generalizations are full of the hazard of specific example. They usually do get too light after significant hammer wear and shaping to maintain tone quality is performed. I usually remove a front key lead after significant shaping. That improves key return and soft playing control.
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#2295073 - 06/25/14 10:51 PM Re: Why and why not adding lead weight to key [Re: Weiyan]
A443 Offline
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Registered: 04/28/12
Posts: 1381
Loc: Manywheres
Wow, Ed McMorrow, RPT, it is nice to read/meet you: I was beginning to think that no one else in the world thought logically and rationally about how the piano functions!!!

This has all been rather frustrating. These concepts are fairly straight forward, and can be easily tested to prove their validity. That is after all, how I came to them in the first place. It's nothing new; it has all been done before all throughout history. These are not wacko theories; if they were, we wouldn't have all arrived at the exact same conclusions. Clearly, you've been at it a lot longer than me; it sounds like others have heard this concept before, yet continue to believe in something different. What is the deal with that? It is not a religion; it's where science meets the needs of the performing arts.

Are there any other thinking, analysing, experimenting, knowledgable technicians out there like yourself? Where is everyone hiding, and why is this even an issue? We can change any and all the variables to create whatever desired outcome the pianist wants. This is clearly awesome. What is wrong with giving pianists what they need to express what the want to artistically?


Edited by A443 (06/25/14 11:00 PM)
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#2295086 - 06/25/14 11:09 PM Re: Why and why not adding lead weight to key [Re: Ed McMorrow, RPT]
Weiyan Offline
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Registered: 10/04/11
Posts: 769
Loc: Hong Kong
Originally Posted By: Ed McMorrow, RPT
Weiyan are you asking about vertical pianos?


Most of my experience is vertical pianos. Grand also in my concern. Once serve a piano teacher's grand, there is 30 gram weight loaded to place not too far behind balance pin hold. I think its better to persuade to remove it, instead to move the weight backward near the backcheck. Add lead at that point causing uneven touch between C maj chord and A flat maj chord.

For uprights, the key stick is so short that the touch is quite is a lot difference from touch the front end to back end of the key. Black keys may have reverse leverage. Its difficult to balance out all keys.

My opinion is better left it as, do less better than more. For those dirty old yamaha better lube it instead to make the key heavier. I want more pro and cons, and consideration about weight the key. I can present the two sides of weighting key to customers.
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#2295093 - 06/25/14 11:13 PM Re: Why and why not adding lead weight to key [Re: Ed McMorrow, RPT]
Paul678 Online   content
500 Post Club Member

Registered: 11/13/13
Posts: 628
Originally Posted By: Ed McMorrow, RPT
Paul687,
There are actions that have such a level of inertia to them that they can injure some pianist when they try to play challenging pieces. It is very easy to overdo the "heavy practice piano syndrome".

In general Yamaha grands are in the higher side of inertia but broad generalizations are full of the hazard of specific example. They usually do get too light after significant hammer wear and shaping to maintain tone quality is performed. I usually remove a front key lead after significant shaping. That improves key return and soft playing control.


Ok, so if I understand you correctly, the hammers themselves get too light after lot's of shaping, so you end up having to remove some of the lead weight in the key, to regain the balance of the system, right?

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#2295098 - 06/25/14 11:19 PM Re: Why and why not adding lead weight to key [Re: Gene Nelson]
Olek Online   content
7000 Post Club Member

Registered: 03/14/08
Posts: 7664
Loc: France
Originally Posted By: Gene Nelson
Olek-
If you want more power - stronger tone - why not weight the hammer?
1/2 gram of brass or lead rod in the moulding does wonders.
It will make your touch heavier by 5 or six times the 1/2 gram and it is easier to do.
Also, the heavier down weight will be combined with a increased upweight of about the same amount minus a little friction making the action faster.
This works only if your action is not too heavy already.


Thanks Gene, I have tried that and was not having a similar tone from one hammer to the next. May be also the hammer shank dynamics is modified in an unusual way.

What I did was using too heavy hammers to begin with, exactly what should not be done!
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#2295101 - 06/25/14 11:27 PM Re: Why and why not adding lead weight to key [Re: A443]
Ed Foote Offline
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Registered: 05/03/03
Posts: 1174
Loc: Tennessee
Originally Posted By: A443
Ed Foote, it is necessary that we learn to see the forest for the trees...

What you have said about the repetition spring and its interaction with key return is entirely correct, but even with the correct back checking height AND drop height, the spring can only partially accelerate/assist the key with its return from a dead stop--there is also a rebounded return where the key is bounced off the bottom of the cushion; the repetition spring plays no meaningful, if any, part of the key's return (e.g., staccato-like attacks, or when the fingers are pulled in for acceleration rather than being pushed straight down).

I know you know this, but the key-lever system is an out-of-balance seesaw--gravity works its affects on both sides of the equation. If the system is only 10g out-of-balance, the return of the key is very slow, just as it would be with a playground seesaw; the keys would not remain in contact with nor support the pianist's fingers on the return. Now, if you put the same system out-of-balance at 100g, it will be fast enough to always remain in contact with the pianist's fingers, no matter how fast the fingers are on the return


Greetings,

If you believe that a five pound ball of lead will fall faster than a 10 pound ball of lead, you logic with adding weight to increase repetition makes sense. I have, with experience, found that not to be true. If you are talking about added weight assisting the keys to bounce off the cushions,(back rail or front punchings?), you are implying that faster repetition comes from out of control movement. I don't think so. The harpsichords I maintain are nowhere close to the imbalance of a piano, yet they play as fast as a human can move the keys.

And, I will add, in 36 years of doing this work, and debating untold times, I have never heard anyone advocating increasing the speed of repetition by increasing the key weight, unless you are comparing the extremes of usable weights. So, if you have groundbreaking research to prove this, I am sure the Journal would love to have your article for peer review.

I believe I saw the forest when Alica De LaRocca told the stage manager that my piano action was the first in her life that she could play everything she wanted as rapidly as she desired, just as she found it. Anytime you would like to compare repetition speed between your actions and mine, just come on over to Vanderbilt and I will be happy to oblige.
Regards,

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#2295109 - 06/25/14 11:44 PM Re: Why and why not adding lead weight to key [Re: Paul678]
Weiyan Offline
500 Post Club Member

Registered: 10/04/11
Posts: 769
Loc: Hong Kong
Originally Posted By: Paul678
Interesting discussion, even if some of it is out of my
experience.

Does Yamaha add lots of lead weight into their piano keys?


Or would it be better to just get the lighter action that suits
my current technique?


There are many ancient Yamaha here. The key feeling is loose for piano in this age. A lot expensive than a new Hailun and Ritmuller. Techs do persuade them to add weight. They even side paid teacher to join the party.
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#2295111 - 06/25/14 11:47 PM Re: Why and why not adding lead weight to key [Re: Weiyan]
Ed McMorrow, RPT Offline
2000 Post Club Member

Registered: 12/09/12
Posts: 2117
Loc: Seattle, WA USA
Ed,
Alicia De LaRocca told me the same thing! Maybe she got confused by our same names.

I think A443 was referring to increased up-weight by reduced front leads speeding up key return.

A443. Thanks for noticing! It does sound like we have come to similar findings. I wrote a text titled; The Educated Piano, in the mid 1980's about LightHammer Tone Regulation, V-bar shaping, and other verboten topics. Steinway NY purchased 7 copies. Cristofori invented light hammers.

Have you perused my PW posts regarding my patent pending Fully Tempered Duplex Scale and the ones on Hybrid Wire Scales?
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#2295112 - 06/25/14 11:47 PM Re: Why and why not adding lead weight to key [Re: Weiyan]
A443 Offline
1000 Post Club Member

Registered: 04/28/12
Posts: 1381
Loc: Manywheres
Thanks, Ed Foote, for the invitation--that is very kind of you--but, do you maybe have a video of perhaps Alborada del Gracisco, L'isle joyeuse, or Gaspard de la nuit on your piano? I can tell most of what I'd need to know by listening and watching.
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#2295115 - 06/25/14 11:52 PM Re: Why and why not adding lead weight to key [Re: Weiyan]
Ed McMorrow, RPT Offline
2000 Post Club Member

Registered: 12/09/12
Posts: 2117
Loc: Seattle, WA USA
Weiyan,
One way you can improve repetition and increase touch weight in a vertical is to lighten the front end of the keys by using a Forstner bit to drill holes through the sides just like they do for installing key leads-but leave them empty. Then if you still want a more firm touch add a small lead to the back of the key as close to the end as possible. It is very easy to ruin the touch by having too much weight in the hammers, keys and action parts.
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#2295124 - 06/26/14 12:22 AM Re: Why and why not adding lead weight to key [Re: Weiyan]
Olek Online   content
7000 Post Club Member

Registered: 03/14/08
Posts: 7664
Loc: France
I think what matters the most in the action is that the parts get together so there is minimum loss when the keys are repeated.
The light inertia key can also be very tiring as the pianist have to follow the keys so yes some energy is expected.
I think pianists are use to control the uncontrollable .
There is of course a range of feel more adapted to different way of apprehending the keyboard, ala harpsichord player or ala A. Schnaebel .

Hopefully different pianos still may be pleasing different pianists.
WHen it comes to Steinway they have things at the limit, what they do cannot be done with a Renner action , and only works because an ensemble of parameters put together.

Forget one and the action does not play right (while it have been getting more tolerant now - out of the softer hammers to make a more easy tone to pianists with problems of touch - or to compensate for something else)


Analyzing their action may lend to the impression hammers are too heavy for the global ratio, for instance.




Edited by Olek (06/26/14 12:31 AM)
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#2295127 - 06/26/14 12:27 AM Re: Why and why not adding lead weight to key [Re: Weiyan]
Olek Online   content
7000 Post Club Member

Registered: 03/14/08
Posts: 7664
Loc: France
I happen to like the tone of light older hammers with a flat crown that compensates for mass, but the attack is damping partials still, an the tone does not seem to project as much (while I mostly have seen that in private homes)

To put in motion such heavy things as wound strings + bridge plus sounboard, a minimum amount of mass is necessary, the max you can accelerate while using action compression, shank/key stiffness reaction, etc

I am certain a piano with rigid keys (no flex an release) at all would be bad.

The pianist is "keeping balls in the air" predictability is certainly a must there, but due to the necessary process the mind of the pianist automatically maps the instrument in regard of inertia an stiffness, then forget it an concentrates on music. wink


Edited by Olek (06/26/14 12:30 AM)
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#2295131 - 06/26/14 12:42 AM Re: Why and why not adding lead weight to key [Re: Ed McMorrow, RPT]
A443 Offline
1000 Post Club Member

Registered: 04/28/12
Posts: 1381
Loc: Manywheres
Originally Posted By: Ed McMorrow, RPT
Alicia De LaRocca told me the same thing!
Me too...almost verbatim.

Ed Foote, let's be honest: we all know the condition of concert pianos out there is generally so poor, that when artists find a 'functioning' piano, they are thrilled beyond belief <---- that's not saying very much. I've been to Carnegie twice in the past few years where a key on the piano simply failed to return at all; luckily, it was not my piano and not my problem. It's all a matter of perspective--I tend to focus more on what the artist is able to say at the piano; that is the only thing that matters to me. I hope you can understand.

Ed McMorrow, RPT, I'll have to go get your book; it sound like a very interesting read! I'll try reading your patent application again; I kind of got side tracked...the patent legalese doesn't necessarily make for an easy/efficient read, especially when I have to also think about the topic at hand and all the implications. ;-)
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Email: klavierbaukuenstler@gmail.com

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#2295135 - 06/26/14 01:03 AM Re: Why and why not adding lead weight to key [Re: Paul678]
Ed McMorrow, RPT Offline
2000 Post Club Member

Registered: 12/09/12
Posts: 2117
Loc: Seattle, WA USA
Paul678,
Yes.
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#2295141 - 06/26/14 01:25 AM Re: Why and why not adding lead weight to key [Re: Weiyan]
Gadzar Offline
1000 Post Club Member

Registered: 12/15/06
Posts: 1775
Loc: Mexico City
Which falls faster? A wooden ball or a ball made of lead?

It has been proved that they fall at the same time.

The acceleration is the same:

G = 9.81 m/s2

So back weight in the keys does not make them to return faster.


Edited by Gadzar (06/26/14 01:39 AM)
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#2295146 - 06/26/14 01:37 AM Re: Why and why not adding lead weight to key [Re: Weiyan]
Olek Online   content
7000 Post Club Member

Registered: 03/14/08
Posts: 7664
Loc: France
There is a neat demonstration of that by Poletti seeing the piano action as 2 weights balanced a rope

https://drive.google.com/file/d/0B6GjQDkF_AMQQVI5Z3NhS3F4cGc/edit?usp=sharing

he leave aside the catapult an kinetic energy. Just about mass.

I also believe that the flexing and release of the action may add acceleration (at what point ?)


that is at the point the acceleration is more than that where the mass begin to be interesting.

PS on Kg of feather fall more slowly than .... wink


Edited by Olek (06/26/14 01:38 AM)
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#2295148 - 06/26/14 01:48 AM Re: Why and why not adding lead weight to key [Re: Weiyan]
Olek Online   content
7000 Post Club Member

Registered: 03/14/08
Posts: 7664
Loc: France
The mass of the front of the key, by braking the key is helping the finger to take more easily control on key flex and hammer shank flex I think.

Yes it may have changed the way piano is played.

Now I think there should be some relation between mass of the key , mass of the pianists arms, and level of acceleration of the hammer/shank.

Heavy keys and low ratio are horrible.

The breaking of inertia gives some immediate tactile return in the finger that knows at that point what the rest of the resistance will be.

WIthin limits - make sense




Edited by Olek (06/26/14 01:49 AM)
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#2295432 - 06/26/14 05:58 PM Re: Why and why not adding lead weight to key [Re: Weiyan]
Gene Nelson Offline
1000 Post Club Member

Registered: 09/10/04
Posts: 1508
Loc: Old Hangtown California
I don't have a lack of understanding.
Just the will to try to pass your litmus test.
Ed explained some of it but consider this:
Olec uses a lead weight at front of key to assist acceleration of hammer and it gets him more force at the string from the hammer.
I add weight to the hammer to increase the force at the string of the hammer.
As I and Ed stated - F=MA so that a starting energy accelerates a hammer to some value giving a force at the string. The same starting energy accelerates a slightly more massive hammer to a slightly slower value giving the same force at the string - all things being equal.
The latter will increase up and down weight while the former will decrease down weight and decrease upweight.
In the real world F=MA works but in the piano action maybe not quite.
Parts flex especially the hammer shank.
Action saturation sets limits.
Pianist can vary the starting energy that accelerates the hammer.
All things being equal one would think that Olec's approach and mine would net the same tonal result but not the case. The heavier hammer gives a better tone.
Have I taken a piano action into a physics lab to measure acceleration and force and observe string vibration patterns? No. but I know how my technique effects touch weight, I can redesign touch weight to cope with what I do and the tone and I can make a heavy hammer work within certain limits. Certainly hammer string contact time is a limit and all of the things I have explained are the tools that I use to avoid and work within this limit - I would not know how to provide scientific data to demonstrate hammer felt resiliance or the voicing techniques that I use or the resulting tone that can be produced - sorry.
Moving 5 and 100 pound weights around has no relevance to piano actions.
What more would you like to know?
BTW - I own Ed McMorrow's book and have read it cover to cover more than once. I refer to it frequently - he is a brilliant technician.

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#2295451 - 06/26/14 06:50 PM Re: Why and why not adding lead weight to key [Re: Gadzar]
Ed Foote Offline
1000 Post Club Member

Registered: 05/03/03
Posts: 1174
Loc: Tennessee
Originally Posted By: Gadzar
Which falls faster? A wooden ball or a ball made of lead?
It has been proved that they fall at the same time.
The acceleration is the same:
G = 9.81 m/s2
So back weight in the keys does not make them to return faster.


No, that is not true, (unless you are dropping them in a vacuum). The 5 lb. ball of lead and the 10 lb. ball of lead will drop the same speed, and two wooden balls of different weights will fall the same, but the density of the lead will have it on the ground before the wooden one, i.e., a 1 lb ball of lead will fall faster than a 100 lb ball of wood.

consider dropping a marble and a marshmallow at the same time. They weigh about the same, but there is a dramatic difference in how fast they fall.
Regards,

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#2295460 - 06/26/14 07:14 PM Re: Why and why not adding lead weight to key [Re: Gadzar]
DoelKees Offline
1000 Post Club Member

Registered: 05/01/10
Posts: 1736
Loc: Vancouver, Canada
Originally Posted By: Gadzar
Which falls faster? A wooden ball or a ball made of lead?

It has been proved that they fall at the same time.

The acceleration is the same:

G = 9.81 m/s2

So back weight in the keys does not make them to return faster.

That would be true if you dropped the key from the leaning tower of Pisa, but not for a pivot mechanism.
Imagine a see-saw rate of fall with 1) One person slightly heavier than the other 2) One person much heavier than the other.

Kees

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#2295476 - 06/26/14 07:37 PM Re: Why and why not adding lead weight to key [Re: Weiyan]
Gadzar Offline
1000 Post Club Member

Registered: 12/15/06
Posts: 1775
Loc: Mexico City
If you add lead to a key, you increment weight but you increment mass (inertia) in the same proportion, the result is you left unchanged the falling acceleration.

In the see-saw the same happens! The heavier person applies a greater force but has a higher mass and that results in the same acceleration.

a = f/m

a acceleration
f force
m mass

If you apply a force with no increment in mass, as with a spring, then you have a greater acceleration.


Edited by Gadzar (06/26/14 07:40 PM)
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#2295494 - 06/26/14 08:05 PM Re: Why and why not adding lead weight to key [Re: Weiyan]
bkw58 Offline

Silver Supporter until December 19, 2014


Registered: 03/14/09
Posts: 1749
Loc: Conway, AR USA
I enjoyed working with the solution MBA brought to the table. Shame, the high cost.
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#2295509 - 06/26/14 08:42 PM Re: Why and why not adding lead weight to key [Re: Gadzar]
DoelKees Offline
1000 Post Club Member

Registered: 05/01/10
Posts: 1736
Loc: Vancouver, Canada
Originally Posted By: Gadzar
If you add lead to a key, you increment weight but you increment mass (inertia) in the same proportion, the result is you left unchanged the falling acceleration.

In the see-saw the same happens! The heavier person applies a greater force but has a higher mass and that results in the same acceleration.

a = f/m

a acceleration
f force
m mass

If you apply a force with no increment in mass, as with a spring, then you have a greater acceleration.

I guess you have never played on one.

Imagine A and B sitting on the see-saw with their feet on the ground and the thing is horizontal. What happens if they lift their feet? 1) A is equal mass to B, nothing happens, acceleration is zero 2) A now downs a big gulp and we repeat. Now the side with A is accelerating very slowly down as he is a bit heavier. 3) Now let A hold a 10kg weight and repeat. I assure you the side A is sitting on will now accelerate much more rapidly.

Kees

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#2295511 - 06/26/14 08:46 PM Re: Why and why not adding lead weight to key [Re: Weiyan]
Gadzar Offline
1000 Post Club Member

Registered: 12/15/06
Posts: 1775
Loc: Mexico City
If you considere an isolated key (no whippen) you'll see that it is a pendulum, the return of the key to its rest position once it is released is only subject to gravity.


There is no other force acting on the key. So the acceleration is no other than G.


Edited by Gadzar (06/26/14 08:53 PM)
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#2295519 - 06/26/14 09:06 PM Re: Why and why not adding lead weight to key [Re: Weiyan]
Gadzar Offline
1000 Post Club Member

Registered: 12/15/06
Posts: 1775
Loc: Mexico City
You all are confusing force with acceleration. By adding weight you increment force but no acceleration.

When you add lead, you add force and mass in exactly the same proportion and thus acceleration is left unchanged!
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Rafael Melo
Piano Technician
rafaelmelo@afinacionpianos.com.mx

Serving Mexico City and suburbs.

http://www.afinacionpianos.com.mx

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#2295544 - 06/26/14 09:48 PM Re: Why and why not adding lead weight to key [Re: Gene Nelson]
DoelKees Offline
1000 Post Club Member

Registered: 05/01/10
Posts: 1736
Loc: Vancouver, Canada
Originally Posted By: Gene Nelson

I add weight to the hammer to increase the force at the string of the hammer.
As I and Ed stated - F=MA so that a starting energy accelerates a hammer to some value giving a force at the string. The same starting energy accelerates a slightly more massive hammer to a slightly slower value giving the same force at the string - all things being equal.

I think you are confusing "force" and "energy". The hammer doesn't really apply any specific "force" to the string, it applies an "impulse". An impulse is a time varying force over a short duration.

Assuming the same force on the key, and the key dip is D, then the energy transferred to the hammer is FD. The kinetic energy of the hammer is .5MV^2 so the strike velocity V is sqrt(2FD/M).

When the hammer, moving at speed V, hits the string it is rapidly decelerated, stops, then accelerating by the string in the opposite direction until the contact is broken. During this process the force on the string looks somewhat like 1/2 period of a cosine, and the total duration of the contact event is proportional to sqrt(M).

So a lighter hammer (smaller M)results in a shorter impact event, which results in more high frequency content, and vice versa.

Of course reality is more complex, but this is the basic physics.

Kees


Edited by DoelKees (06/26/14 09:48 PM)

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#2295565 - 06/26/14 10:57 PM Re: Why and why not adding lead weight to key [Re: Weiyan]
BDB Offline
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Registered: 06/07/03
Posts: 21583
Loc: Oakland
I am of the opinion that no matter what the mass of the hammer, the string will attempt to bounce it back in 1/f seconds, where f is the frequency of the note. How successful it is at that depends on a number of properties of the hammer, and mass is only one of them.
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#2295571 - 06/26/14 11:15 PM Re: Why and why not adding lead weight to key [Re: BDB]
DoelKees Offline
1000 Post Club Member

Registered: 05/01/10
Posts: 1736
Loc: Vancouver, Canada
Originally Posted By: BDB
I am of the opinion that no matter what the mass of the hammer, the string will attempt to bounce it back in 1/f seconds, where f is the frequency of the note. How successful it is at that depends on a number of properties of the hammer, and mass is only one of them.

Sounds like a reasonable approach to refine the physics intuitively. But what is f? The fundamental? The strongest partial?

Long time ago I looked at hitting a bell with a metal hammer. If the hammer impacts, the local surface is propelled away but returns very rapidly to collide again with the hammer; this would correspond to your f being one of the higher partials. After this second collision the process repeats several times, each event involving lower partials and more complex motions of the bell. These multiple impacts (called micro-collisions in the literature) are an essential feature in determining the resulting sound.

For the case at hand it is even more complex, as the hammer itself is not rigid, and the contact area also comes onto play.

Yet the conclusions from the "level 1" approximation, that a lighter hammer excites relatively more higher partials (resulting in a "thin" sound) remains valid I think.

Kees

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#2295580 - 06/26/14 11:39 PM Re: Why and why not adding lead weight to key [Re: Weiyan]
BDB Offline
Yikes! 10000 Post Club Member

Registered: 06/07/03
Posts: 21583
Loc: Oakland
Unless the string is vibrating in another mode, the frequency is the fundamental. There is only one string. There are no other strings vibrating at any other frequencies.
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