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#1937290 - 08/04/12 12:31 PM Re: Kawai Resonance Issue [Re: Bogs]
BDB Offline
Yikes! 10000 Post Club Member

Registered: 06/07/03
Posts: 20747
Loc: Oakland
This topic has become an argument about diction, the choice of words, rather than a discussion of the physics of piano sound.
_________________________
Semipro Tech

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#1937294 - 08/04/12 12:36 PM Re: Kawai Resonance Issue [Re: BDB]
Emmery Offline
2000 Post Club Member

Registered: 04/02/08
Posts: 2328
Loc: Niagara Region, On. Canada
Originally Posted By: BDB
This topic has become an argument about diction, the choice of words, rather than a discussion of the physics of piano sound.


Exactly. Sometimes when one reaches into a bag of weapons and finds none there, they resort to using the bag as a club.
_________________________
Piano Technician
George Brown College /85
Niagara Region

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#1937301 - 08/04/12 12:57 PM Re: Kawai Resonance Issue [Re: Bogs]
Olek Offline
6000 Post Club Member

Registered: 03/14/08
Posts: 6338
Loc: France
1 / 1 ; the window can also vibrate because bass frequencies carry more in solids than in air. indeed in both cases it is resonance. I suggest that the whole panel of the window is large enough to react to some low frequencies.

some kind of tuning of the windows occur there. ..

in the pian the bridge vibrates at different rates, the neighbour strings only react when the rate is enough for them.
then it sound its fundamental frequency, only exited by the bump of the hammer. If you put a finger on the bridge you can feel the vibrations. the neighbour strings filter and tunes the vibrations of the bridge...
hence my point a global better soundong of pianos :
with high level of consonance
with springy pins and lively upper segments.
_________________________
Isaac OLEG - http://picasaweb.google.fr/PianoOleg pro

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#1937346 - 08/04/12 02:35 PM Re: Kawai Resonance Issue [Re: Chris Leslie]
Jerry Groot RPT Offline
6000 Post Club Member

Registered: 11/07/07
Posts: 6828
Loc: Grand Rapids Michigan
Originally Posted By: Chris Leslie
Originally Posted By: Jerry Groot RPT

I still wonder, why a person would do this to a piano or anything else in the first place? Again, what purpose does it serve?


If some pianos have this effect then there may be implications for the sonority of the piano when using the sustain pedal. I would imagine increased cacophony if many adjacent un-dampened notes are more easily excited at their fundamental.


Holding down a note intentionally making it not play, and then seeing how many surrounding notes you can get to sound through it, or how many you cannot make sound, and then complaing about it, wondering if that is normal, is ridiculous. It is not normal to do that to begin with.

That, in and of itself, serves no useful purpose for the playing of the instrument. That was my point. What pianist plays the piano that way anyway? None that I know of.
_________________________
Jerry Groot RPT
Piano Technicians Guild
Grand Rapids, Michigan
www.grootpiano.com

We love to play BF2.

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#1937356 - 08/04/12 03:19 PM Re: Kawai Resonance Issue [Re: Bogs]
BDB Offline
Yikes! 10000 Post Club Member

Registered: 06/07/03
Posts: 20747
Loc: Oakland
Stravinsky's Serenade en La uses silently depressed notes to hold certain sounds, as do a number of pieces by other composers. The most notable piece is Ives' Concord Sonata, which calls for a block of wood to hold a cluster of notes. Even Paganini from Carnival by Schumann plays a bunch of loud chords with the pedal, and then plays another chord almost silently, which is held while the pedal is let up. The latter chord is heard without attack.
_________________________
Semipro Tech

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#1937360 - 08/04/12 03:29 PM Re: Kawai Resonance Issue [Re: Emmery]
Minnesota Marty Online   content

Platinum Supporter until October 5 2014


Registered: 05/15/12
Posts: 6054
Loc: Rochester MN
Emmery,

My credentials in the field are not relative to the general discussions at Piano World. I clearly state my name and location in my signature line.

If you must know, I hold a Master of Science in Acoustical Engineering from Loyola University. I need not defend my statements to you. Your window analogy is flawed for the reasons I have noted. My credentials are not derived by means of Google.

This is a discussion group. My curriculum vitae is not prerequsite to my participation in this forum. My musical credentials also are not necessary for participation in these forums. Those credentials are the intellectual and practical basis for my skill as a performing pianist and do not require posting on a billboard.

When you venture into analogy based on flawed scientific deduction, your misconception should be presented to the forum. I did just that.
_________________________
Marty in Minnesota

It's much easier to bash a Steinway than it is to play one.

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#1937374 - 08/04/12 04:21 PM Re: Kawai Resonance Issue [Re: BDB]
Cinnamonbear Offline
3000 Post Club Member

Registered: 01/09/10
Posts: 3722
Loc: Rockford, IL
Originally Posted By: BDB
This topic has become an argument about diction, the choice of words, rather than a discussion of the physics of piano sound.


Don't they all, eventually? This one just happened sooner than most. Hitler. I will say, though, I am so glad for your most recent post, BDB, regarding the holding down of keys, silently, in a musical context per composition per recognized great composers.

Did you learn something, Jer? wink

P.S. What an awesome thread!

(Thanks Horowitzian! grin )

P.P.S. I like Leghetti, too, especially with CHAS sauce.


Edited by Cinnamonbear (08/04/12 04:29 PM)
Edit Reason: added "post script" and "post post script"
_________________________
I may not be fast,
but at least I'm slow.

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#1937384 - 08/04/12 05:04 PM Re: Kawai Resonance Issue [Re: Olek]
Cinnamonbear Offline
3000 Post Club Member

Registered: 01/09/10
Posts: 3722
Loc: Rockford, IL
Originally Posted By: Kamin
1 / 1 ; the window can also vibrate because bass frequencies carry more in solids than in air. indeed in both cases it is resonance. I suggest that the whole panel of the window is large enough to react to some low frequencies. [...]


I suggest the window needs to be re-glazed with Fletcher Terry Glazier Push Points, which distribute weight better than traditional 08-111 Diamond [shaped] Fletcher Terry Glazier Point for Professional Driver No. 1. These particular push points should be used wherever windows are glazed on truck routes, imho. Then, we can get back to talking about why adjacent strings vibrate. (BTW, DAP latex window-glazing-in-a-tube glazing compound is not the same as DAP '33' glazing compound in a tub. Very, very different compounds with very different properties. Wholly different, in fact..., although they both hold the window in, ultimately...)*

Upon further testing on the Lester, I noticed that B2 and C#3 made silently held C4 ring. I also noticed that B4 and C#5 made an upper partial of silently held C4 ring. Someone please learn me. Or, at least, school me. Or, at the very least, teach me.

Thank you, Jer, for leRnin' me where B0 starts.

And, I do mean leRnin'.

_____
* Did I just split an infinitive??!? Or, what? (ala Edie Arlisa Brickell)
_________________________
I may not be fast,
but at least I'm slow.

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#1937385 - 08/04/12 05:11 PM Re: Kawai Resonance Issue [Re: Cinnamonbear]
Cinnamonbear Offline
3000 Post Club Member

Registered: 01/09/10
Posts: 3722
Loc: Rockford, IL
Phew. BO stinks! Good thing B0 doesn't! In most cases. Unless tuned incorectly.*

_____
*and I do mean incorectly.
_________________________
I may not be fast,
but at least I'm slow.

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#1937396 - 08/04/12 05:55 PM Re: Kawai Resonance Issue [Re: BDB]
pianoloverus Online   content
Yikes! 10000 Post Club Member

Registered: 05/29/01
Posts: 19096
Loc: New York City
Originally Posted By: BDB
Stravinsky's Serenade en La uses silently depressed notes to hold certain sounds, as do a number of pieces by other composers. The most notable piece is Ives' Concord Sonata, which calls for a block of wood to hold a cluster of notes. Even Paganini from Carnival by Schumann plays a bunch of loud chords with the pedal, and then plays another chord almost silently, which is held while the pedal is let up. The latter chord is heard without attack.
Which means that what Jerry said is true only 99.9999999999999999999999999% of the time.

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#1937402 - 08/04/12 06:04 PM Re: Kawai Resonance Issue [Re: Bogs]
Jerry Groot RPT Offline
6000 Post Club Member

Registered: 11/07/07
Posts: 6828
Loc: Grand Rapids Michigan
Hahaha!!! 99.999999 % of the time. I like to be right that much! smile ,

Funny Andy!

I'm setting thinking BO or, BS? haha.

Some people (idiots in my opinion) also compose music to be played in chords in the lowest octaves of the piano. That makes the piano sound horrible tuning wise, to me and to most reputatble technicians. We get the nost complants from people playing the piano in the manner. Does that mean the piano should be played that way then? Just because someone wrote something for it or, thought of it? Or, thinks it sounds good?? Noooooo but, they do it anyway... Hey, I know, I might as well use my iPAD for a cutting board! There's an idea! smile Whatever blows your hair back.... Once again, I say, what useful purpose does the OP have for doing what he is doing? I repeat. No useful purpose.

By the way, I lost my glasses recently today, as a matter of fact, so I can barely see what I am typing let along what you said so if there are more than usual, mistakes, da'ts what fer how come! I blind bat now... frown

_________________________
Jerry Groot RPT
Piano Technicians Guild
Grand Rapids, Michigan
www.grootpiano.com

We love to play BF2.

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#1937405 - 08/04/12 06:23 PM Re: Kawai Resonance Issue [Re: Jerry Groot RPT]
Cinnamonbear Offline
3000 Post Club Member

Registered: 01/09/10
Posts: 3722
Loc: Rockford, IL
Originally Posted By: Jerry Groot RPT
[...] Hey, I know, I might as well use my iPAD for a cutting board! [...]

ROTFL!!! laugh laugh laugh *

_____
*Is that "diction"?
_________________________
I may not be fast,
but at least I'm slow.

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#1937409 - 08/04/12 06:32 PM Re: Kawai Resonance Issue [Re: Jerry Groot RPT]
Cinnamonbear Offline
3000 Post Club Member

Registered: 01/09/10
Posts: 3722
Loc: Rockford, IL
Originally Posted By: Jerry Groot RPT
[...] Does that mean the piano should be played that way then? Just because someone wrote something for it or, thought of it? Or, thinks it sounds good?? [...]


What if...

Somebody composed something because their tuner tuned their piano a certain way, and it sounded good because of the way the composer composed it because of the way the tuner tuned it?!? Tonal Temperament (TT), anyone? Anyone????

grin
_________________________
I may not be fast,
but at least I'm slow.

Top
#1937413 - 08/04/12 06:46 PM Re: Kawai Resonance Issue [Re: Bogs]
BDB Offline
Yikes! 10000 Post Club Member

Registered: 06/07/03
Posts: 20747
Loc: Oakland
There is a sonata for a 5 + 7 tuned piano in one of Owen Jorgensen's book. The piano is tuned with the 5 black keys equal tempered and the 7 white keys equal tempered, as opposed to the 12 chromatic keys being equal tempered. Then there is Harry Partch's music, using a 69 note per octave just intonation, not for piano, but he did tune some harmoniums that way. There are also a number of pieces for quarter tones, sometimes with pianos especially made, sometimes with two pianos.

All of these are probably less successful than the various ways of using resonances within a piano. After all, that has always been available, and the most important pedal on the piano, the damper pedal, relies on them.
_________________________
Semipro Tech

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#1937438 - 08/04/12 07:29 PM Re: Kawai Resonance Issue [Re: BDB]
Cinnamonbear Offline
3000 Post Club Member

Registered: 01/09/10
Posts: 3722
Loc: Rockford, IL
Originally Posted By: BDB
There is a sonata for a 5 + 7 tuned piano in one of Owen Jorgensen's book. The piano is tuned with the 5 black keys equal tempered and the 7 white keys equal tempered, as opposed to the 12 chromatic keys being equal tempered. Then there is Harry Partch's music, using a 69 note per octave just intonation, not for piano, but he did tune some harmoniums that way. There are also a number of pieces for quarter tones, sometimes with pianos especially made, sometimes with two pianos.

All of these are probably less successful than the various ways of using resonances within a piano. After all, that has always been available, and the most important pedal on the piano, the damper pedal, relies on them.

Ha-ha-ha! Sometimes, BDB, you are truly amazing! smile
_________________________
I may not be fast,
but at least I'm slow.

Top
#1937510 - 08/04/12 09:38 PM Re: Kawai Resonance Issue [Re: Minnesota Marty]
Emmery Offline
2000 Post Club Member

Registered: 04/02/08
Posts: 2328
Loc: Niagara Region, On. Canada
Originally Posted By: Minnesota Marty
Emmery,

My credentials in the field are not relative to the general discussions at Piano World. I clearly state my name and location in my signature line.

If you must know, I hold a Master of Science in Acoustical Engineering from Loyola University. I need not defend my statements to you. Your window analogy is flawed for the reasons I have noted. My credentials are not derived by means of Google.

This is a discussion group. My curriculum vitae is not prerequsite to my participation in this forum. My musical credentials also are not necessary for participation in these forums. Those credentials are the intellectual and practical basis for my skill as a performing pianist and do not require posting on a billboard.

When you venture into analogy based on flawed scientific deduction, your misconception should be presented to the forum. I did just that.


First of all Marty, this discussion was originally dealing with peoples thoughts, analogies and theories on a decent subject. You claim I made an analogy with the window pane that was incorrect. I responded that the analogy is not mine, found in countless text books, articles, citations, Wiki ect...

Instead of making a valid explanation of your view, or actually looking to see why exactly this analogy is used by countless experts, you abondon everything by suddenly claiming your expertise puts you beyond all that. You brought in credentials, I didn't.

Like I said, if a truck engine vibrates at a specific rpm, and a window on a nearby home rattles because of it, but then stops when the rpm changes, that is sympathetic resonance. Called an acoustical engineer in Guelph, he also confirms the analogy is correct. He also confirmed that an mechanical vibration that isn't sympathetic (as you claim) will rattle that window through a wide range of frequency. Marty, you are missing this important difference. Non sympathetic vibration will work in a wide frequency range...the analogy mentioned states the opposite.
_________________________
Piano Technician
George Brown College /85
Niagara Region

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#1937531 - 08/04/12 10:39 PM Re: Kawai Resonance Issue [Re: Emmery]
Minnesota Marty Online   content

Platinum Supporter until October 5 2014


Registered: 05/15/12
Posts: 6054
Loc: Rochester MN
Originally Posted By: Emmery
Originally Posted By: Minnesota Marty
Emmery,

My credentials in the field are not relative to the general discussions at Piano World. I clearly state my name and location in my signature line.

If you must know, I hold a Master of Science in Acoustical Engineering from Loyola University. I need not defend my statements to you. Your window analogy is flawed for the reasons I have noted. My credentials are not derived by means of Google.

This is a discussion group. My curriculum vitae is not prerequsite to my participation in this forum. My musical credentials also are not necessary for participation in these forums. Those credentials are the intellectual and practical basis for my skill as a performing pianist and do not require posting on a billboard.

When you venture into analogy based on flawed scientific deduction, your misconception should be presented to the forum. I did just that.


First of all Marty, this discussion was originally dealing with peoples thoughts, analogies and theories on a decent subject. You claim I made an analogy with the window pane that was incorrect. I responded that the analogy is not mine, found in countless text books, articles, citations, Wiki ect...

Instead of making a valid explanation of your view, or actually looking to see why exactly this analogy is used by countless experts, you abondon everything by suddenly claiming your expertise puts you beyond all that. You brought in credentials, I didn't.

Like I said, if a truck engine vibrates at a specific rpm, and a window on a nearby home rattles because of it, but then stops when the rpm changes, that is sympathetic resonance. Called an acoustical engineer in Guelph, he also confirms the analogy is correct. He also confirmed that an mechanical vibration that isn't sympathetic (as you claim) will rattle that window through a wide range of frequency. Marty, you are missing this important difference. Non sympathetic vibration will work in a wide frequency range...the analogy mentioned states the opposite.


I am missing nothing. If you really called one of my colleagues (unnamed), you obviously did not quote your own analogy exactly as written. Your analogy is incorrect and I have pointed out exactly why. You are now tempering it in an attempt to prove it true. Many of the things you have stated, are defending a premiss which is not the original.

I was the one who brought up credentials?

Originally Posted By: Emmery
Your own "expertise" however appears self proclaimed, and not important enough to even put in your signature.


If the truck changes gears, the window will still rattle. I does not negate the mechanical vibration being transmitted to the window frame. The intensity of the rattle may change or even stop. It has nothing to do with sympathetic vibration. There may, in fact, be minor resonance between the glass and the truck, but it is mechanical vibration, not sympathetic vibration, causing the glass to rattle.

You are wrong. You need not attempt to teach what I have already learned through formal education.

Please send me the bibliography of your sources to substantiate your claim.
_________________________
Marty in Minnesota

It's much easier to bash a Steinway than it is to play one.

Top
#1937538 - 08/04/12 11:19 PM Re: Kawai Resonance Issue [Re: Minnesota Marty]
DoelKees Offline
1000 Post Club Member

Registered: 05/01/10
Posts: 1540
Loc: Vancouver, Canada
Originally Posted By: Minnesota Marty

If the truck changes gears, the window will still rattle. I does not negate the mechanical vibration being transmitted to the window frame. The intensity of the rattle may change or even stop. It has nothing to do with sympathetic vibration. There may, in fact, be minor resonance between the glass and the truck, but it is mechanical vibration, not sympathetic vibration, causing the glass to rattle.

A loose window in a pane is a highly nonlinear system and the usual concepts of resonance don't quite apply. Rattling can occur at pretty much any frequency, but only if the excitation force is just right. You basically bounce the glass back and forth between its points of attachments. With a higher force you can make it rattle at a higher frequency.

For linear systems this is not true. The resonance response is directly proportional to how close the excitation frequency is to the natural resonance of the system and is independent of the excitation force.

I guess this shows that piano's are complex nonlinear systems, not easily emulated by digital keyboards.

Long time ago I was woken up in Holland by a rattling window which I assumed was caused by a truck which was not supposed to be allowed to drive through the narrow street I lived in.

It turned out to be caused by a small earthquake caused by gas extraction cave collapse some 100 Km away. It had just the right frequency and force to make it happen.

Kees (Credentials available on request)

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#1937599 - 08/05/12 06:13 AM Re: Kawai Resonance Issue [Re: pianoloverus]
Olek Offline
6000 Post Club Member

Registered: 03/14/08
Posts: 6338
Loc: France
Originally Posted By: pianoloverus
Originally Posted By: BDB
Stravinsky's Serenade en La uses silently depressed notes to hold certain sounds, as do a number of pieces by other composers. The most notable piece is Ives' Concord Sonata, which calls for a block of wood to hold a cluster of notes. Even Paganini from Carnival by Schumann plays a bunch of loud chords with the pedal, and then plays another chord almost silently, which is held while the pedal is let up. The latter chord is heard without attack.
Which means that what Jerry said is true only 99.9999999999999999999999999% of the time.


How good to go with the flow then ! (I dont trust your number anyway)
I just cannot understand how, a piano technician, that is supposed to work for and with musicians, may belive that music may be some basic 3 or 4 chords and simple tunes derived from religious hymns for the main part.

That is so much of a simplified ,reduced point of view on the richness of our world that it escapes me. (I believe it is due to early mind programming)

When looking at it more closely even the origins of those actual standards where richer, rhythmically speaking most often but also from melody point of view.

End of the rant

I just heard yesterday a radio program on Alan Lomax & family , very interesting samples of treasures from the past.
_________________________
Isaac OLEG - http://picasaweb.google.fr/PianoOleg pro

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#1937602 - 08/05/12 06:33 AM Re: Kawai Resonance Issue [Re: Minnesota Marty]
Olek Offline
6000 Post Club Member

Registered: 03/14/08
Posts: 6338
Loc: France
Originally Posted By: Minnesota Marty
Originally Posted By: Emmery
Originally Posted By: Minnesota Marty
Emmery,

My credentials in the field are not relative to the general discussions at Piano World. I clearly state my name and location in my signature line.

If you must know, I hold a Master of Science in Acoustical Engineering from Loyola University. I need not defend my statements to you. Your window analogy is flawed for the reasons I have noted. My credentials are not derived by means of Google.

This is a discussion group. My curriculum vitae is not prerequsite to my participation in this forum. My musical credentials also are not necessary for participation in these forums. Those credentials are the intellectual and practical basis for my skill as a performing pianist and do not require posting on a billboard.

When you venture into analogy based on flawed scientific deduction, your misconception should be presented to the forum. I did just that.


First of all Marty, this discussion was originally dealing with peoples thoughts, analogies and theories on a decent subject. You claim I made an analogy with the window pane that was incorrect. I responded that the analogy is not mine, found in countless text books, articles, citations, Wiki ect...

Instead of making a valid explanation of your view, or actually looking to see why exactly this analogy is used by countless experts, you abondon everything by suddenly claiming your expertise puts you beyond all that. You brought in credentials, I didn't.

Like I said, if a truck engine vibrates at a specific rpm, and a window on a nearby home rattles because of it, but then stops when the rpm changes, that is sympathetic resonance. Called an acoustical engineer in Guelph, he also confirms the analogy is correct. He also confirmed that an mechanical vibration that isn't sympathetic (as you claim) will rattle that window through a wide range of frequency. Marty, you are missing this important difference. Non sympathetic vibration will work in a wide frequency range...the analogy mentioned states the opposite.


I am missing nothing. If you really called one of my colleagues (unnamed), you obviously did not quote your own analogy exactly as written. Your analogy is incorrect and I have pointed out exactly why. You are now tempering it in an attempt to prove it true. Many of the things you have stated, are defending a premiss which is not the original.

I was the one who brought up credentials?

Originally Posted By: Emmery
Your own "expertise" however appears self proclaimed, and not important enough to even put in your signature.


If the truck changes gears, the window will still rattle. I does not negate the mechanical vibration being transmitted to the window frame. The intensity of the rattle may change or even stop. It has nothing to do with sympathetic vibration. There may, in fact, be minor resonance between the glass and the truck, but it is mechanical vibration, not sympathetic vibration, causing the glass to rattle.

You are wrong. You need not attempt to teach what I have already learned through formal education.

Please send me the bibliography of your sources to substantiate your claim.


Please guys, you are not wrong none of you, I get the difference now, you are in semantics...

I wish however to see the credentials wink a scan of the diplomas would be perfect, with id card, passport, may be some genetic imprint, so I will be sure I exchange with a knowledge person !!! wink


Edited by Kamin (08/05/12 06:41 AM)
_________________________
Isaac OLEG - http://picasaweb.google.fr/PianoOleg pro

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#1937693 - 08/05/12 11:58 AM Re: Kawai Resonance Issue [Re: Bogs]
Minnesota Marty Online   content

Platinum Supporter until October 5 2014


Registered: 05/15/12
Posts: 6054
Loc: Rochester MN
Hi Isaac,

I have sent you my blood sample for the required DNA testing.

_________________________
Marty in Minnesota

It's much easier to bash a Steinway than it is to play one.

Top
#1937702 - 08/05/12 12:24 PM Re: Kawai Resonance Issue [Re: Minnesota Marty]
Emmery Offline
2000 Post Club Member

Registered: 04/02/08
Posts: 2328
Loc: Niagara Region, On. Canada
Originally Posted By: Minnesota Marty
Originally Posted By: Emmery
Originally Posted By: Minnesota Marty
Emmery,

My credentials in the field are not relative to the general discussions at Piano World. I clearly state my name and location in my signature line.

If you must know, I hold a Master of Science in Acoustical Engineering from Loyola University. I need not defend my statements to you. Your window analogy is flawed for the reasons I have noted. My credentials are not derived by means of Google.

This is a discussion group. My curriculum vitae is not prerequsite to my participation in this forum. My musical credentials also are not necessary for participation in these forums. Those credentials are the intellectual and practical basis for my skill as a performing pianist and do not require posting on a billboard.

When you venture into analogy based on flawed scientific deduction, your misconception should be presented to the forum. I did just that.


First of all Marty, this discussion was originally dealing with peoples thoughts, analogies and theories on a decent subject. You claim I made an analogy with the window pane that was incorrect. I responded that the analogy is not mine, found in countless text books, articles, citations, Wiki ect...

Instead of making a valid explanation of your view, or actually looking to see why exactly this analogy is used by countless experts, you abondon everything by suddenly claiming your expertise puts you beyond all that. You brought in credentials, I didn't.

Like I said, if a truck engine vibrates at a specific rpm, and a window on a nearby home rattles because of it, but then stops when the rpm changes, that is sympathetic resonance. Called an acoustical engineer in Guelph, he also confirms the analogy is correct. He also confirmed that an mechanical vibration that isn't sympathetic (as you claim) will rattle that window through a wide range of frequency. Marty, you are missing this important difference. Non sympathetic vibration will work in a wide frequency range...the analogy mentioned states the opposite.


I am missing nothing. If you really called one of my colleagues (unnamed), you obviously did not quote your own analogy exactly as written. Your analogy is incorrect and I have pointed out exactly why. You are now tempering it in an attempt to prove it true. Many of the things you have stated, are defending a premiss which is not the original.

I was the one who brought up credentials?

Originally Posted By: Emmery
Your own "expertise" however appears self proclaimed, and not important enough to even put in your signature.


If the truck changes gears, the window will still rattle. I does not negate the mechanical vibration being transmitted to the window frame. The intensity of the rattle may change or even stop. It has nothing to do with sympathetic vibration. There may, in fact, be minor resonance between the glass and the truck, but it is mechanical vibration, not sympathetic vibration, causing the glass to rattle.

You are wrong. You need not attempt to teach what I have already learned through formal education.

Please send me the bibliography of your sources to substantiate your claim.


Marty, because the original topic in the posting has to do with resonance, the analogy I copied copied and presented had to do with resonance. Resonance phenomena can occur from mechanical resonance, acoustic resonance, electromagnetic resonance, nuclear magnetic resonance (NMR), electron spin resonance (ESR) and resonance of quantum wave functions. Sympathetic resonance will occur from mechanical conveyance of the energy along side of non-sympathetic resonance. This is why the rattle can occur at a specific frequency and diminish or dissappear at different frequencies.

The part I put in bold in your quote is incorrect. Mechanical resonance can also be sympathetic. It is a specific frequency where the input mechanical vibration matches the resonant frequency of the object and/or its interface with another object closely and the natural dampening qualities of the object is reduced or negated. I
In the case of a rattle on a window which is not solid in its frame is dependant on the clearance between them. A wide clearance will correspond to a slower frequency, a narrow clearance will respond to a higher frequency. It this case the resonance is based on the interface of the two objects.

On a piano, the wide spectrum frequencies of the hammer blow attack (not the string harmonics) are being mechanically conveyed through the bridge to other strings. If part of that spectrum matches the natural resonant frequencies of another string, these will become more pronounced comparatively. A buzz from a loose rib can also occur at specific frequencies and this too is dependant on the fit between them.




Edited by Emmery (08/05/12 12:48 PM)
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#1937731 - 08/05/12 01:12 PM Re: Kawai Resonance Issue [Re: Emmery]
Withindale Offline
1000 Post Club Member

Registered: 02/09/11
Posts: 1795
Loc: Suffolk, England
Originally Posted By: Emmery
On a piano, the wide spectrum frequencies of the hammer blow attack (not the string harmonics) are being mechanically conveyed through the bridge to other strings.


A possible explanation for adjacent strings becoming excited is mechanical transfer through the bridge and soundboard system:
  • The impulse resulting from the hammer strike produces some movement of the bridge in the string direction.
  • This movement produces smaller movements at the adjacent strings.
  • Those movements are sufficient to set the adjacent strings vibrating.
Whether this effect will happen or not depends on the piano. My piano does not exhibit it but Phil's does. Kawai say the GE-20 does and Maurus hears it on his Shigeru Kawai SK-2.

As Kawai try to make their digital pianos sound as realistic as possible by "harmonic imaging", it seems the effect results from the design and construction of their grand pianos.

I wonder if adjacent notes sounding off was intentional or an accidental by-product of some other design goal.


Edited by Withindale (08/05/12 01:17 PM)
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Schiedmayer & Soehne, 1925 Model 14, 55" upright
Ibach, 1922 49" upright (project piano)

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#1937994 - 08/06/12 02:41 AM Re: Kawai Resonance Issue [Re: Emmery]
maurus Offline
500 Post Club Member

Registered: 05/21/11
Posts: 752
Originally Posted By: Emmery
Kees, I've heard linguolabial trills with more depth and musical quality than what Musica Ricercata has to offer...I'm sad to say. When an artist gathers enough recognition to put out trash or nothing as an example of their work...the only thing more silly are the critics who waste their breath talking about it.

Its in the same league as Cages' 4' 33" (opening and closing the piano lid)....

http://www.youtube.com/watch?v=HypmW4Yd7SY

and Robert Rauschenbergs' "White Paintings"...




Interesting to what lengths this thread about a rather simple phenomenon has gone. And thanks for pointing out your aesthetic preferences to us, Emmery.
_________________________
Shigeru Kawai SK-2, etc.

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#1938087 - 08/06/12 09:52 AM Re: Kawai Resonance Issue [Re: Bogs]
Olek Offline
6000 Post Club Member

Registered: 03/14/08
Posts: 6338
Loc: France
WHen I was younger there where window panel tuners, it was queite a common profession.

They pass in the streets ringing a bell and singing "window tuner" , "window tuner" .

They used a trcuck engine mounted on a dolly to detect which panels wher vibrating and wt which frequencies so they could adapt the technology used to the kind of vibrating detected.

Unfortunately all those simple and traditional trades have been lost today, the adoption of less noisy exhaust systems have ruined them. just a few remain around airports



BTW some of my my windows ring at the B1 C2 range, because of the surface of the panel probably.


Edited by Kamin (08/06/12 09:57 AM)
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