"Fully Tempered Duplex Scale" Tech article coming March

Posted by: Ed McMorrow, RPT

"Fully Tempered Duplex Scale" Tech article coming March - 01/31/13 10:48 PM

I suppose this is a type of a brag but I thought an announcement here would help inform the field.

I have a Patent applications pending titled "Fully Tempered Duplex Scale", (FTDS). If you attended my class at the 2012 PTG Nat'l convention you already know about it. I exhibited a Steinway B and Baldwin R that have been modified to display some of the technology my invention covers.

The March issue of "The Piano Technicians Journal" features an article by me describing what I have done in the realm of duplex scaling to rise to the level of invention. Of course I still have to complete the Patent examination process.

A FTDS can play a very significant role in producing an even, dynamic, sustained treble tone that blends well with the middle of the compass. I have done several pianos now with this feature and the response of musicians is very positive. I believe my FTDS shows that I have solved the vast majority of duplex/capo noise issues.

I am seeking to license FTDS to important parts of the piano industry. If you would like to play and hear exemplar FTDS pianos, I am in the Seattle area.

I hope my fellow technicians will read my article at least!
Posted by: Craig Hair

Re: "Fully Tempered Duplex Scale" Tech article coming March - 02/01/13 07:42 AM

Wow, I'm floored.
Someone who actually takes duplexing seriously. (As opposed to seriously scorning it.)
I guess its time to get that associate membership.
Posted by: Emmery

Re: "Fully Tempered Duplex Scale" Tech article coming March - 02/01/13 08:55 AM

I haven't really bothered with dealing with duplex scales on older models when I tune. Recently I did some checks on a Hailun 178 and was quite surprised how the duplex 5ths just fell into place with standard tuning methods. Just go the usual amount sharp to render the back string and drop back to pitch and it remarkably falls into place by design.
Posted by: alfredo capurso

Re: "Fully Tempered Duplex Scale" Tech article coming March - 02/01/13 09:47 AM


Hi Ed,

Thanks for informing on PW.

You wrote: ..."I have a Patent applications pending titled "Fully Tempered Duplex Scale", (FTDS)."...

This sounds interesting. What do you mean when you say "fully tempered"?

..."If you attended my class at the 2012 PTG Nat'l convention you already know about it."...

Unfortunately I was not there.

..."I exhibited a Steinway B and Baldwin R that have been modified to display some of the technology my invention covers."...

How were those pianos "modified"?

..."The March issue of "The Piano Technicians Journal" features an article by me describing what I have done in the realm of duplex scaling to rise to the level of invention."...

Is it possible to know what you have done, here in PW?

..."Of course I still have to complete the Patent examination process."...

Leave Patent aside, are you able to supply more information?

..."A FTDS can play a very significant role in producing an even, dynamic, sustained treble tone that blends well with the middle of the compass."...

I share your believe. About the "middle of the compass", may I ask you what would your reference be? In other words, how would you tune the middle compass? Do you tune "aurally"?

..."I have done several pianos now with this feature and the response of musicians is very positive."...

Is there any recording, perhaps a comparison of the kind.. "before and.. after"?

...I believe my FTDS shows that I have solved the vast majority of duplex/capo noise issues."...

Would you be able to expand on "duplex/capo noise issues"?

..."I am seeking to license FTDS to important parts of the piano industry. If you would like to play and hear exemplar FTDS pianos, I am in the Seattle area."...

I cannot visit you (right now), but I would love to be able to appreciate your invention, compared to a usual duplex.

..."I hope my fellow technicians will read my article at least!"

I too would like to read your article, for sure! For the time being, all the best for your project,

Regards, a.c.
.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 02/01/13 10:37 AM

Craig Hair;
There have been pianos in the Seattle are where the duplex was removed-so for me-recognizing the lack of tone was a no brainer. Glad you are in the "club" with me!

Emmery;
I think you may be referring to what I call the hitching length and others call the rear duplex. The article covers the front duplex, although the patent involves aspects of the hitching lengths behavior also.

A.C.;
If I posted the article here, I would be disrespecting the PTGJ Editor and Publisher. I am seeking to have a version of the article placed in Europiano and so far no rejection. You can subscribe to the PTGJ or order one copy of the March issue from PTG.org
Posted by: BDB

Re: "Fully Tempered Duplex Scale" Tech article coming March - 02/01/13 11:49 AM

Perhaps you could summarize what the advantages are.
Posted by: alfredo capurso

Re: "Fully Tempered Duplex Scale" Tech article coming March - 02/01/13 01:13 PM

Originally Posted By: BDB
Perhaps you could summarize what the advantages are.


And perhaps reply on other general items:

Originally Posted By: alfredo capurso

...Sniped...

What do you mean when you say "fully tempered"?

..."A FTDS can play a very significant role in producing an even, dynamic, sustained treble tone that blends well with the middle of the compass."...

I share your believe. About the "middle of the compass", may I ask you what would your reference be? In other words, how would you tune the middle compass? Do you tune "aurally"?

Is there any recording, perhaps a comparison of the kind.. "before and.. after"?

...I believe my FTDS shows that I have solved the vast majority of duplex/capo noise issues."...

Would you be able to expand on "duplex/capo noise issues"?

Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 02/02/13 11:18 PM

Please note; when I use the term "duplex" I mean the string length between the capo bar and the string rest nearest the tuning pin.

BDB,
The advantages that the "Fully Tempered Duplex Scale" has is that it solves the following problems:

FTDS eliminates the unnatural "whistles" and "chiming" sounds that sometimes accompany some notes of the typical duplex scale. Creates are more dynamic, full, (I like this descriptive term, Steinway used it a lot) sustained treble tone. Provides for a more complete utilization of the "pivot termination" conditions that reduces string fatigue. Perfectly blends the tone of the duplex portion of scale with the agraffe section. Reduces hammer impact noise and it's transmission into the plate. Creates a more smother rendering of the string over the string rests when tuning. (There are other advantages but I want to be brief).

A.C.,
My term "Fully Tempered" used in conjunction with the term "Dulpex Scale" is derived from the way the T-modes and L-modes of the struck string, duplex length, and hitching length are established between themselves and their place in the compass. These relationships are "balanced" in a way somewhat similar the how we balance beat rates amongst the musical intervals when we tune.

I am sorry I cannot "scoop" the PTGJ so you will have to wait a bit for further details. Thank you for your interest and I hope to continue this conversation in the future.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/09/13 03:39 PM

If you want to read my article it is now available online at;
PTG.org
click on "view the PTG Journal"
click on "Journal PDF"
click on "March 2013"
I look forward to your comments.
Thanks Ed
Posted by: ando

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/09/13 04:17 PM

Originally Posted By: Ed McMorrow, RPT
If you want to read my article it is now available online at;
PTG.org
click on "view the PTG Journal"
click on "Journal PDF"
click on "March 2013"
I look forward to your comments.
Thanks Ed


Couldn't you just post a direct link?
Posted by: Withindale

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/09/13 04:27 PM

Originally Posted By: ando
Couldn't you just post a direct link?

PTG members only, I imagine, as login needed.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/09/13 05:15 PM

Ando; No I don't know how to post direct links.
Withindale; PTG Journal online as PDF is available to all. If you repost you must attribute for copyright.
Posted by: jim ialeggio

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/09/13 05:35 PM

http://www.ptg.org/userfiles/file/ptj/pdf/PTJ-2013-3.pdf
Posted by: CC2 and Chopin lover

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 06:46 AM

Could someone elaborate on why the agraffe set up could not just be continued into the treble section? What was it about that section of the instrument that necessitated the creation of the capo bar, which seems to me like a much less effective form of string termination?
Posted by: James Carney

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 08:12 AM

Originally Posted By: CC2 and Chopin lover
Could someone elaborate on why the agraffe set up could not just be continued into the treble section? What was it about that section of the instrument that necessitated the creation of the capo bar, which seems to me like a much less effective form of string termination?


88 agraffes are possible - Bechstein is noted for doing that.

The presence of the capo bar allows front duplex scaling, which most manufacturers incorporate into their designs.
Posted by: CC2 and Chopin lover

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 08:22 AM

Seems a lot of the issues of false beats, buzzing and improper string alignment could be eliminated, or greatly reduced, by just employing agraffes across the entire scale. In those Bechsteins that have already employed this approach, has anyone shown them to have less in the way of tonal color and complexity? Why is the rear duplex not sufficient to attain the desired effect?
Posted by: James Carney

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 08:51 AM

Play a Bechstein and hear for yourself what full agraffes sound like. It's a different experience.

It is quite possible to have capo sections with front duplex scaling and no false beats and perfect hammer/string alignment. Bosendorfer, Forster, Bluthner, and Steingraeber come to mind. I'm always amazed at how clean they are - they rarely have false beats, and if they do they can almost always be corrected.
Posted by: CC2 and Chopin lover

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 09:57 AM

Yes, but the question persists, why can't the same effect be accomplished with just the rear duplex? Also, why couldn't one create a front duplex system that worked with agraffes? Examining this photo:

http://www.precisionpianoservices.com/images/steinwaypianoduplex4-lg.jpg

one could easily see where the "V" bar could be eliminated, the plate could be extended distally and a set of agraffes could be drilled and inserted at the exact point where the string currently makes contact with the "V" bar. You could leave the duplex bars in place, while maintaining the same termination points, so as not to upset the scaling of the piano, and eliminate all the "typical" issues associated with the capo bar in the piano brands that did not make Mr. Carney's rather elite list.
Posted by: Olek

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 10:05 AM

ALso, in the high treble, having the hammers striking at the good location is not easy if there are agrafes, compromises are used (overblow) if not the hammer will touch the plate.

Strings lenght is more precise with agrafes, in the case of Bechsteins, string lenght differences within unisons could be similar from note to note. the advantage is only there, and there are more inconvenience, as less direct tone transmission within plate, so no "active plate" choice (and no front duplexes of course then)

The plate in the high treble is mostly "coloring" the impact tone.
Posted by: Larry Buck

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 10:22 AM

I would sat that front duplex scaling can be done either with or without replacing the duplex with agraffes.

A capo has a different attack, one many seem to prefer.

A clean sound quires very good terminations. It does not take an agraffe to have that.

Additionally, drilling for agraffes high in the treble is tricky so close to the edge of the casting. Those agraffes are tilted toward the speaking length partly for hammer clearance and partly to make sure the agraffe threaded hole is well supported.

A Capo does save manufacturing time and the difference of tone is only subjective. They both are good.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 11:23 AM

Bechsteins with 88 agraffes have bad false beats when the string path between the speaking length and the tuning pin through the agraffe is not straight.

The first duplex arrangement I know of was Steinway "Monitor" grands which had 85 agraffes.

My Fully Tempered Duplex Scale, (FTDS), in it's most beneficial employment would have special agraffes in the capo. I have yet to do that version.

As Olek also points out, I will add though that note 88 strike point is usually just under 3mm from the termination point. With 88 agraffes there is no room to get that close without gluing the top hammers on longer and at a rake to tip them back towards the ideal strike point.

Duplex scales of the prior art have noises and create uneven tone where the typical capo bar scale switches to agraffes and the top treble is weak and often ugly, sometime awful ugly! My FTDS solves those problems.
Posted by: Larry Buck

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 11:46 AM

Originally Posted By: Ed McMorrow, RPT


As Olek also points out, I will add though that note 88 strike point is usually just under 3mm from the termination point. With 88 agraffes there is no room to get that close without gluing the top hammers on longer and at a rake to tip them back towards the ideal strike point.


Ed, when over centering shanks, are not the angle of the shanks to hammer's center line obtuse and the hammers are bored slightly short ..?

Posted by: Larry Buck

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 11:53 AM

Originally Posted By: Ed McMorrow, RPT

Duplex scales of the prior art have noises and create uneven tone where the typical capo bar scale switches to agraffes and the top treble is weak and often ugly, sometime awful ugly! My FTDS solves those problems.


I might disagree here, We pay careful attention to termination, belly work and voicing.

I believe we have a fairly seamless transition from agraffe to capo ....
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 11:56 AM

Ed,
On the 2 I have re-hammered, I lengthened bore slightly and swept a rake into the bore on the top 10 or so hammers-so as to avoid over-centering there-because any hammer wear will shift strike point shallower more rapidly.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 12:08 PM

Larry,
I am sure your work is fine. But I have proven my FTDS makes a treble better. I am not proposing that without it your trebles will all be dead-but it does make an even, clean, singing, more easily tuned, treble compass possible. All prior art duplex scales can not be voiced as evenly nor as powerfully as an FTDS scale. You will have to hear it to understand.
Ed Sutton has been quite skeptical of Techs who think they have invented something new, at the 2012 convention I invited him to hear two of my pianos and after 15 seconds of playing and looking the first words out of his mouth were "now THAT is different".

The full complement of elements I am describing have yet to be done all in one piano. I have filed for 44 claims, of course I will probably not get them all, I may not get any if the patent office just throws up their arms and says that there is too much prior art. I may have to take a piano to the Patent office because hearing is believing.
Posted by: Larry Buck

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 12:15 PM

Ed,

I have read Jim Ellis's work, plodded through Conklin's work, studied Theodores 1872 patent on Duplex's, have a copy of Helmholtz third edition, Transcription by Ellis and am reading through that attempting to understand his potential influence on Theodore ..... what defines yours as different?
Posted by: Olek

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 01:35 PM

Originally Posted By: Larry Buck
Originally Posted By: Ed McMorrow, RPT


As Olek also points out, I will add though that note 88 strike point is usually just under 3mm from the termination point. With 88 agraffes there is no room to get that close without gluing the top hammers on longer and at a rake to tip them back towards the ideal strike point.


Ed, when over centering shanks, are not the angle of the shanks to hammer's center line obtuse and the hammers are bored slightly short ..?



Well that is how it was on older Bechstein, with a larger rake angle sometime, but only to allow the strike near the string termination enough.

(over center (or overblow) was also used just to adapt to the large plate deformation noticed on some pianos at older times. I noticed one up to 6mm differnce between center and the extremes, and the original hammers had then that overblow and 94 ° rake angle- very bad for the core of the knuckles in the end, due to the lateral pressure on them they bend)

The larger rake angle is not an obligation, as there is generally a large angle coming from the bridge (may be less on Bechsteins in the end but 3° are not uncommon on Steinways)

The shape of those old hammers was so thin they often twist in time, unfortunately. it is always a problem when changing them.
Hopefully a few mm more on the shank is not that a problem in the high treble.(but the front side have often to be filed a lot for the last high treble notes)
Posted by: Olek

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 01:36 PM

Overblow (with 1° angle minimum) is considered as a security to allow more open FFF nuances, via probably more shank flexing.
Posted by: Mark Davis

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 02:55 PM

Originally Posted By: Ed McMorrow, RPT
PTG Journal online as PDF is available to all.


Hello Ed,

This is great news but I wonder if you are not mistaken?

When did this take place?

I was under the impression that only members of the PTG and paying subscribers were allowed to view the journal.

Why would some have to pay for it and others not?

Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 11:48 PM

Larry,
There are several problems capo bars with duplex scales have and I am sure you have heard them all.
The problems are:
Snare drum, sizzle like sound that is heard at the fundamental frequency.
Pulsing, chiming sound that pulses with the fundamental but includes pulsing at higher partials.

The snare sizzle can be from either and/or; a too rounded V bar or a duplex length that is too close to a harmonic ratio with the speaking length.

The chiming sound is from the beats that arise between L-modes due to the divergent speaking lengths of the unison strings both at the V bar and at the duplex rest.

The pulsing, chiming sound is L-mode beats coming in and out of strong coupling with T-mode- again because of divergent speaking lengths plus duplex lengths too long for this place in the compass.

I do not know how to verify these descriptions with measurement. I do not see how the L-modes could be measured because the strings are so close together that there is no room for discrete magneto pickups. But I think my hypotheses is proven by the design it inspired. There are simply no other vibratory mode mechanisms to use to describe the origins of the sounds. Ellis's work proves L and T-mode beating/coupling.

Let take the venerable Stein B as an example;
C52 is the first capo/duplex note. On all the stock B's I have ever heard the tone of this note compared to B51 has an extra metallic shimmer to it that limits how full it can be voiced. Note 51 often has false sounds and duller tone due to poor string spacing and too soft string rest felt. Note 52 has a too long duplex and note 51 can have a too soft string rest which create a tonal scale break that most people probably just take as a fact of life that nothing can be done about.

You ask me what is different from Ellis and Conklin; they studied L-modes in the lower half of the compass.
Different from Helmholtz; I don't remember him having much to say about L-modes beyond the fact that they occur.
Different from Steinway; They got the front duplex ratios wrong in the patent, the hitching lengths (rear duplex) are better left closer to the fundamental, L-modes can not travel through the string over the bridge, I place the non-harmonic duplex ratios in the compass in such a way so as to maximize pivot termination (the pivot termination principle Steinway got right), at the highest point in the compass and blend the pivot effect into the reduced pivot conditions where the agraffe section begins. I eliminate, (at least in all the ones I have done so far) pulsing, chiming L-mode interactions by using a duplex string rest that essentially damps L-mode but not T-mode and that is very slippery to the string.

I also have claims regarding capo bar shape, capo bar mounting or stiffening methods, capo bar vibration control elements, agraffe mounting methods, hitching length proportions across the compass, and string contact elements at the bridge.

Does this help clear it up some? I do hope all who are interested will read my article carefully so I do not have to rewrite it a 100 times here. But I do appreciate the attention!
Posted by: RoyP

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 11:54 PM

I have been able to download the article on a couple computers. So I think it's accessible to anyone from the above link.

I wonder whether there is a correlation between the use of a capo bar and higher string tensions? Most of the pianos of which I am aware that use agraffes all of the way to the top tend to be European, such as the Bechstein. My understanding is that the new C.Bechstein line has a capo bar, and is designed to have more power, etc. Is this scale higher tension?

Sorry Ed. You posted while I was writing.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 11:56 PM

Roy,
The new Bechstein scale may have a capo but it most certainly does not have a "Fully Tempered Duplex Scale"!
Posted by: RoyP

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/12/13 11:59 PM

I suppose it doesn't!

I would like to hear one of your pianos. I was in Seattle last summer, but somehow missed it.
Posted by: Larry Buck

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 04:34 AM

Thanks Ed for your explanation.

I did read your article.

Yes, Helmholtz doesn't list longitudinal comments in either the contents or index.

Ellis cites the enormous difficulty in terminating longitudinal mode. Could you comment on how you are able to terminate this mode?

As far as the difficulties with the B scale at B4 and C5, I have been able to resolve the issues you describe. Terminations, Belly design, hammer choice, regulation and voicing have been sufficient. I don't attribute all of the instances you describe to the design as you describe it. I like the B scale as designed.

We have been working with a Dr.of Physics, His T/A and the local University for the last couple of years on Longitudinal modes in piano strings. His T/a will be by this Thursday for some "quality" time with a couple of pianos. Resonant vs non resonant front and back scale questions are actually on the table.

I am not questioning that you have achieved a successful sound and I would like to hear what you have done. I do want to HEAR what you say has been "eliminated" as well as "added". Any chance you will be at MARC this year?
Posted by: Roy123

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 08:01 AM

Ed,

I read your article, which contains many interesting ideas. It seems to me that an implicit assumption you make is that a front tuned duplex is necessary, or at desirable. There are some pianos that are designed not to require a tuned front duplex because the shape of the bearing point of the strings as they go under the capo bar, and the angle of the strings as they come off the capo are such that no (or de minimis) energy leaks across the front termination. In such a design, there is no possibility of loss of string energy due to a somewhat lossy termination (i.e., the transmission of string energy across the capo bar is not perfect), there are no longitudinal modes in the duplex section because there are no string vibrations in the duplex section, and therefore the various noises, whistles, and chimes that you describe can't exist.

The advantages claimed for pianos designed not to have string energy bleed across the capo are an increased sustained, and an improved tone. It seems from your description that a piano using the front termination taught by your patent may well sound very similar. I am interested in your comments.

Thanks
Posted by: James Carney

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 09:06 AM

Ed, is there a piano with your FTDS in New York City? Or will you have one at MARC or the Chicago convention?
Posted by: Olek

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 09:12 AM

It sound difficult to admit that Lmodes can pass thru the capos easily, however the front segment could be exited by, as energy seem to be able to attain even the tuning pin.
Any string segment may work as a resonator, but for Lmode I like to see what is the level of motion that correspond to the frequencies.

or do I miss something in the Lmode transmission schemes ? it seem clear (!) when I thing of the bridge and the wire itself, but the agrafe or capo part seem neutral enough to me.

the excitation that is perceived at the pin side, is it coming from the wire, or from wave reflected waves in the case and plate ?
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 10:51 AM

Roy123,
I most definitely have proven that a FTDS duplex design in the treble makes the tone better than any other prior art. I have the single most important proof; the pianos! Now we are left to argue why. I have tried my best to use what is known about L-mode and T-modes and their interactions to explain why. The FTDS is the result of the test of my hypotheses.

The counter bearing angle of the duplex string segment has no relation to L-mode reflection. Since L-mode is carried internally in the string, some of it from the localized tension differences the hammer strike produces it with, go right over the V-bar. It then can be reflected by the duplex rest. This is how each unison generates 6 different fundamental L-modes.

BB Mason/Hamlins have steep duplex counter bearing and they always have several notes that chime.

Monotone duplex designs can have the duplex damped or undamped with felt. The damped ones usually have no duplex noises but the tone sustains less and is more nasal. Monotone duplexes do not optimize pivot termination conditions across the compass. The Acetal co-polymer duplex rests I use, (and any other suitable material that damps L-mode and doesn't damp T-mode are claimed) damp L-mode and do not damp T-mode. This is different than the prior art. Felt damps T-mode.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 11:04 AM

Larry,
The L-mode termination issue Ellis struggled with is related to bridge rocking and resonances within the monochord structure.

Most pianists and technicians have come to expect and ignore many of the subtle duplex chiming noises the duplexes of the prior art all contain. I think if you listen carefully to your pianos you will find some-especially if you voice the treble up fully to equal the rest of the compass in volume for playing effort expended. Most pianos have weak trebles-especially if they have wonderful basses to contrast it with. All prior art duplexes have a tonal break where the agraffes end and capo begins.

I very much like the tone of the B scale. One of my FTDS pianos is a 1984 B. It has the best treble tone of any piano I have ever heard in my life. It did not sound that way before I modifies it to FTDS.

I have not been invited to either MARC or 2013 PTG Institute. I would be open to bringing a piano and presenting a lecture if the conditions were workable.
Posted by: BDB

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 11:27 AM

Originally Posted By: Ed McMorrow, RPT
Roy123,
I most definitely have proven that a FTDS duplex design in the treble makes the tone better than any other prior art...


I am immediately suspicious of proofs of any sort of esthetics, since not everyone has the same esthetic values. The use of the word "proof" in your article is inaccurate.

Recordings might be more convincing than claims of proof.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 12:09 PM

BDB,
I hope you enjoy your suspicions. If you read my article I hope you noticed the prefatory paragraph Ed Sutton appended. He is a well known sceptic of "new" piano inventions.

I do not think tone quality, in a fundamental way, is taste. There is good taste and bad taste.

My theoretical foundation for tone is a concept I developed called "Musically Intelligible Sound", (MIS). It is rooted in combining linguistics, operatic vocal technique, the standard two terms form of defining the tone of an individual piano note, (I have my own preferred words for each part, )and my original contribution being; placing three categories of sound across the compass of the keyboard. MIS was to be the centerpiece of my second book titled; "Grand DeLight", subtitled; "The Natural Tongue of Piano Tone and Touch". I have 13 chapters roughed in but have not gone further due to other interests.

BDB my "proof" is the only one that matters to musicians!
Posted by: BDB

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 12:24 PM

As I said, recordings would be welcome. Ideally, it should be "before" and "after" recordings with everything else the same on the piano. That is, if the piano is restrung during the process, the piano needs to be restrung in the "before" recording.

Testimonials are rarely proof. I am reminded of the story of the pile of crutches left at a shrine, and the note left there by someone who understands this: "One wooden leg would be sufficient!"
Posted by: Mark Davis

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 12:41 PM

Originally Posted By: Mark Davis
Originally Posted By: Ed McMorrow, RPT
PTG Journal online as PDF is available to all.


Hello Ed,

This is great news but I wonder if you are not mistaken?

When did this take place?

I was under the impression that only members of the PTG and paying subscribers were allowed to view the journal.

Why would some have to pay for it and others not?



Ok, I queried with the PTG and Ed Sutton, responded with, "it is being changed to members only?".

So, we leave it there and to the PTG






Posted by: Zeno Wood

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 01:13 PM

What are you talking about? Are you looking for some sort of conspiracy? If the Journal was available on line to non-members of the PTG, then it was an oversight related to running a klunky website that has now been corrected.
Posted by: Mark Davis

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 01:59 PM

I am leaving all of this stuff alone as this is not my fight, but the PTG's.
Posted by: adamp88

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 02:50 PM

I'm a bit confused. If it was incorrect for Jim to post that link, then that's on Jim. You seem to be implying something broader?
Posted by: Mark Davis

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 03:20 PM

I will leave all of this stuff to the professionals.

Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/13/13 09:41 PM

I agree with Zeno-our PTG website is clunky!

My apologies to all who cannot access the article. If you send me your mailing addresses I will send a photo copy of the article to all who are interested-except BDB- it sounds like I might have to send him a whole piano!
Thanks Ed
Posted by: Olek

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/14/13 05:56 AM

Hello Ed,

yes I wish to read the doc, I have on the site but now it is not possible.

I suggest that you pass recordings of notes before and after.

Even with basic microphone that kind of analysis is not so difficult to provide in my opinion.

I dont understand why we dont seem more spectra analysis from the people providing piano wire, pitch locks, and other goodies that are supposed to clean or optimise a part of the tone.

SImply dont get why, even basic recording misses.

WHat is provided is recordings of pianos with 6-8mlikes and a lot of sound treatment, sometime, or tuners playing with the sustain pedal engaged.

However, I am all for reasearchs and discovering new things.

YEst the font duplexes are not providing a clean tone by themselves, I suppose they playu a role more in the dynamics (adbsorbing part of the impact hardness) than to enlight the spectra

SO you say that the L waves are passing thru the inner pârt of the wire ? this need to be examinated, as I understand the wire is deformed under the hammer impact, but this deformation is supposed to be stopped by the agrafe or the capo.

(while certainly there is something that passes from the wire to the tuning pin, at last with a hard blow the original wave is what allows to test pin setting or to create it, depending of the tuning method used. (it also allows to add a little tension in the front segment after having lowered it when tuning)

How can you detect the presence of Lmodes in the front segments ? with accelerometers , or with the method tou developped (where the presence is ascertain by its loss, if I understand well) ?

Please let us hear what it is about, whenever possible.

You, as a reasearcher, certainly have recorded samples as it is the case in all acoustical researches. Could you provide them please ?

All the best

Isaac OLEG
Posted by: jim ialeggio

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/14/13 08:24 AM

Isaac,

What equipment do you use to make the on-site demonstration recordings you've posted on the forum? I have found several of them demonstrate the point you were trying to make very well, while obviously not being a professional recording.

I'm thinking of 2 recordings in particular from, I think, the Unison thread:

1-tuning treble unisons with the sustain pedal engaged
2-also in the Unison thread, it was a pianist "testing" a CHAS tuning

In both of these the sound was not professional, but still the point and the sound made it through quite well, despite the manner of recording.

Jim Ialeggio
Posted by: Roy123

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/14/13 08:29 AM

Originally Posted By: Ed McMorrow, RPT

I most definitely have proven that a FTDS duplex design in the treble makes the tone better than any other prior art.


That proof would be quite an undertaking. To prove, for example, that the FTDS duplex design was better than a piano designed not to bleed energy across the capo, you'd have to take two identical pianos, prepare and voice them the same way, and verify by means of some measurements that their treble sections gave identical tones (to some agreed upon extent). Then, you'd have to modify one using the FTDS techniques and the other not to bleed energy across the capo. You would have to verify, by some objective tests, that the modifications to both pianos were competently designed and executed, i.e., they produced some objective standard of performance. Then, both pianos would have to be prepped and voiced to bring out their best tone--not just any best tone, but a best tone that was, in some aesthetic way, comparable (boy, would that be a task fraught with problems). Then, by means of listening and some additional objective tests, decide which one sounded better, or, in fact, if they just sounded somewhat different, but in a way that could not be classified as better or worse. The listening tests would have to be double blind to be of any worth.

Until such tests were done, I would have to say that your assertion about the superiority of FTDS design was somewhat anecdotal.
Originally Posted By: Ed McMorrow, RPT

The counter bearing angle of the duplex string segment has no relation to L-mode reflection.

Yes, I believe this is true.

Originally Posted By: Ed McMorrow, RPT

Since L-mode is carried internally in the string, some of it from the localized tension differences the hammer strike produces it with, go right over the V-bar.


Well, the L mode is much like sound in air. Just as sound in air causes compression and rarefaction, and also produces movement in air molecules, the L mode produces longitudinal movement of the string--if it didn't how would the L-mode energy be coupled to parts of the piano that could vibrate and produce sound? The extent to which the L mode can go through the capo termination would depend on the details of the termination. You apparently have determined that using a particular plastic dampens L modes. Perhaps that plastic could be used at the string-bearing point of the capo and damp L modes there. If so, a piano could use this feature and also use a high enough string angle over the capo not to bleed T mode energy across the capo, and therefore may have the superior sustain of such a design.

Originally Posted By: Ed McMorrow, RPT

BB Mason/Hamlins have steep duplex counter bearing and they always have several notes that chime.


If M&H BBs have tuned front duplexes one must assume that the design of the capo does not stop T-mode string energy from crossing the capo.

Originally Posted By: Ed McMorrow, RPT

Monotone duplex designs can have the duplex damped or undamped with felt. The damped ones usually have no duplex noises but the tone sustains less and is more nasal.


I believe that this statement is not true in general, though it might be true of some poorly designed monotone duplexes. Also, consider that any T-mode energy that bleeds across the capo is T-mode energy that is no longer in the string. It would be difficult to believe that T-mode energy in the string can make it past the capo into the tuned duplex section, and then make it through the capo again into the main portion of the string without substantial energy loss. Therefore, one would think that a piano designed not to bleed T-mode energy across the capo would have superior sustain, other things being equal. If I may indulge in an anecdotal statement, I have played a piano designed not be bleed energy across the capo, and this piano had neither a nasal tone, nor short sustain.

Originally Posted By: Ed McMorrow, RPT

Monotone duplexes do not optimize pivot termination conditions across the compass.


If, by a pivot termination you mean one in which the string effectively pivots at the capo due to T-mode vibrations, then you are indeed correct--a piano designed with a monotone duplex is, or at least, should be, designed to have a true, full termination at the capo, in which nothing crosses the capo. If fully successful, no L- or T-mode energy would cross such a capo.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/14/13 12:08 PM

ROY123,
The people who can evaluate whether my FTDS works are ones who have heard many pianos, and particularly the scales with prior art duplexes, and have heard the same scales with FTDS. They recognize the improvement. As some level the double blind sort of A to B test you are requiring looks good on paper, and if I were seeking tenure at University would be needed, but to provide practical service to musicians-"I don't need no stinking badges" (To quote the banditos from the movie Treasure of The Sierra Madre).

At some level all that matters is that an FTDS makes a piano function better as a musical instrument and provides a more stable regime for those elements. My thinking may seem different than many of the tropes that have become standard about pianos, but I think it is simpler, and based on known physics. What I have uncovered is that inaudible L-modes can produce audible beats.

My claims involve capo bar elements that stiffen and damp L-mode. I have not made an instrument with all of the elements in place in one piano.

The importance of pivot to the very short treble strings cannot be overstated. The T-mode must be able to flex the portion of string between the V-bar and the duplex rest. Even when you get down to the agraffe section, placing the agraffe side of the string rest felts 10mm or so behind them and using the densest felt produces an audible difference. As does chamfering the agraffe string holes so as to allow the fullest pivot string motion. I have verified all of this with A to B comparisons.

My apologies to all who expect me to set up a recording studio and then post the clips here. I would rather spend the time making another instrument.

I do have a long professional track record of successful innovation which Mr. Sutton aknowledged in his prefatory paragraph. I know that is saying "Trust me" but that is where I am at.

I have heard several pianos which have been changed from a duplex to a monotone and they all had weaker, thinner treble tone.
Posted by: kpembrook

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/14/13 12:29 PM

Originally Posted By: Ed McMorrow, RPT
ROY123,
As some level the double blind sort of A to B test you are requiring looks good on paper, and if I were seeking tenure at University would be needed, but to provide practical service to musicians-"I don't need no stinking badges" (To quote the banditos from the movie Treasure of The Sierra Madre).


I would agree. Double-blind tests to disprove the null hypothesis are entirely appropriate for drugs and medical procedures where people's lives are at stake. However, this is not by any means the only way to "know" something. In fact, only a microscopic percentage of all we know comes to us that way. To suggest we won't reliably know something about Ed's development until we exhaust what might well be the entire piano industry's R&D budget for a few years just isn't real.

Certainly it's not appropriate to dismiss or muzzle small innovators when their presentation is well-reasoned and reflects some sort of practical interaction with the real world through direct observation of phenomena. This is NOT to say that there shouldn't be questions and critiques as time goes along. Those are entirely appropriate. But to dismiss something or someone just because they don't have a corporate research budget won't be helpful to consideration of innovation in our morbidly conservative industry.
Posted by: jim ialeggio

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/14/13 12:42 PM

Originally Posted By: Ed McMorrow
Even when you get down to the agraffe section, placing the agraffe side of the string rest felts 10mm or so behind them and using the densest felt produces an audible difference.


Could you clarify the language here. S&S has a "ski slope" of felt in the tenor agraffe section which behaves as a mushy, high friction, kind'a counter-bearing (a bit of a pain to the tuner sometimes). Are you saying placing dense felt on the non-speaking side of the agraffe, in addition to the ski slope?

Also if this is what you are describing, how does it assist the pivot, being so close to the agraffe. Or, are you differentiating between pivot and L mode damping in the treble sections and L mode damping only in the tenor agraffe sections.

A pic would be helpful if you could manage it.


Jim Ialeggio

Posted by: Phil D

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/14/13 07:01 PM

Originally Posted By: Ed McMorrow, RPT

My apologies to all who expect me to set up a recording studio and then post the clips here. I would rather spend the time making another instrument.

I do have a long professional track record of successful innovation which Mr. Sutton aknowledged in his prefatory paragraph. I know that is saying "Trust me" but that is where I am at.

I have heard several pianos which have been changed from a duplex to a monotone and they all had weaker, thinner treble tone.


I've been following this thread with great interest, as this sounds like a big innovation. I'm on board with the physics and the rationale, but I don't have rebuilding or designing experience, I can only relate to what I have encountered wtih existing duplex scaling. Hence, I'm probably a bit more easily convinced than others on this forum! grin

I just wanted to jump in here because I believe it is not unreasonable for people to want to hear samples of this technology. Nobody is asking you to set up a recording studio - in fact Isaac is bemoaning the lack of really simple recordings that just get the message across - if your technology makes the kind of difference to the sound that you seem to be claiming, then there's no requirement for a professional recording to bring it out - simply any recording using an external microphone, of an untreated piano and a piano with the FTDS. Even a very simple recording of an ascending major scale in the treble of your FTDS-equipped B would be illuminating, I'm sure - do it with your phone, even.

I'm not asking for scientific comparison. I'm just curious what it sounds like, as I'm sure a great number of other people here are!
Posted by: alfredo capurso

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/14/13 07:50 PM


Nice post, Phil, thanks.

Hi Ed,

Plus one.
Posted by: accordeur

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/14/13 08:06 PM

Yes, nice post Mr. Dickson.
Posted by: ando

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/14/13 09:15 PM

Originally Posted By: accordeur
Yes, nice post Mr. Dickson.


Agreed, this whole thread is too secretive. It's all words and no action. I gather Ed is trying to somewhat protect this idea, but it's coming across as a bit cagey. No pictures, no sound, just concepts. How exactly are people supposed to evaluate this technology?
Posted by: BDB

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/14/13 09:47 PM

I can understand that until the patent is granted the details should not be gone into. I have also been willing to give the benefit of the doubt for inaccurate use of scientific claims. But I would like to hear a demonstration. There have been too many claims of miracle discoveries around here that, when we actually get to hear them, are not that impressive. I, for one, am not about to recommend that anyone buy a self-tuning piano, or a granite bridge, after hearing the samples.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/15/13 01:18 AM

Thanks Keith for a well said post!

Olek and A.C.; PM your addresses and I will send article to you.

Jim; Reduce the width of the paperboard string rest by about 7mm at note 51 and taper that off about 15 notes below. Bond the densest woven felt appropriate to the paperboard and place it about 10mm behind agraffe 51. Make overall thickness enough to make a solid, definite point of contact at the agraffe edge of the ski-slope string rest.

Phi D; Call me at 01-425-299-3431 on march 19th between 9:00AM and 6PM US west coast time and I will play the treble over the phone for you. That is the first day I will have the shop to myself again since a bunch of music teachers are using my showroom for classes for the next few days.

ANDO; I think you must realize that musical instruments must be directly experienced to have a truly meaningful experience. One of these days I will get my web-site up and it will have recordings of each piano I have available. As of now other activities take precedence.

BDB; Again I can't send you an FTDS piano-but I have and do demonstrate them to all who desire to come by my shop. Or when I am invited to present at a PTG or close facsimile thereof group-I will bring a piano if it is at all possible. I am with you on the self-tuning granite piano, (did I just say that or is someone stoned out of their mind?). FTDS is the real deal my friends and I am very proud of it. I also will say that there are many many wonderful pianos without it-but it does make it easier to make a beautiful treble. Warm with power. Plus it blends across the compass seamlessly.
Posted by: ando

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/15/13 02:35 AM

Originally Posted By: Ed McMorrow, RPT


ANDO; I think you must realize that musical instruments must be directly experienced to have a truly meaningful experience. One of these days I will get my web-site up and it will have recordings of each piano I have available. As of now other activities take precedence.


Ed, I have no doubt that what you are working on has great merit. I have looked into the L mode problem in some depth and believe addressing this is pivotal to building a supreme sounding piano. The fact that you have made a rigorous study of this and implemented a carefully calculated solution is a credit to you.

I just think it should be a matter of utmost priority to include some sound examples of what your modifications do to the sound of a piano. The discussion itself is very interesting and stimulating, but it really needs the sound example for the points to be driven home.

I think you are vastly overstating the effort and difficulty of making some recordings and posting them. There are any number of ways you can post recordings quickly, easily and for free. They don't need to be hosted on your own site at this point. All you need is some clickable links in threads like this one and you will be greatly advancing this debate.

If you want any help or suggestions with how to do this, feel free to PM me. It's really quite easy. As far as making the recordings goes, there are numerous portable recorders that are capable of very high quality and save in various formats that are ready to transfer to a suitable host that we can all access (I myself use a very inexpensive Roland R-09 digital recorder, it's more than adequate for this purpose - built in high-fidelity stereo condenser mics, able to record in wav or mp3 format of any quality level). I urge you to give this some thought.
Posted by: BDB

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/15/13 03:02 AM

The more difference, the worse the recording can be! Chromatic scales are sufficient. You might be able to do it with a phone or a laptop computer. You can always listen and decide for yourself if it shows what you want it to show.
Posted by: Olek

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/15/13 05:21 AM

1° Sorry for the rant, ED wink

WHat I say is that when we talk of L modes we should record them, we can hear them so they can be recorded.

Then the specrtra shows the amount of L mode in a given note.
They are particularly easy to point in recordings as their frequency does not change.

Anytime I am unsure of what I hear, and if time permit I record it and look at the display when listening to the recorded note.

Anyway this is a very pretty basic part of any acoustical work and should be included as part of the proof when a theory is theorized.

It is done for tunings , it is done for voicing, it is done for testing wire quality, the factories use spectra analysis since the 50's and now the equipemnt is availeable to any computer owner , so no need for "laboratory material"

Even accelerometers can be find if the theory is to be worked at a higher level .

But I record with a simple H2 on a laptop, so I dont get how studies on tone can be done without recordings, this is simply missing to your credibility.

I had a demonstration of a goodie that is p^roduced by a Swiss tech, that is supposed to help the tone by neutralizing some disturbation to high frequencies caused by static electricity (or some similar concept)

Difficult to say if it works as we are in placebo effect range there.
I heard something, others also, some hear nothing, I even heard a less good tone on a less than good piano.

Then if there is ANY tone change, it can be recorded.
I recorded and seem to find a cleaner spectra BUT there it was difficult the differnce is almost not audible.

SO I left the analysis and recording job to the inventor of the goodie, who is also making speakers, si he is supposed to know a thing or twoo about spectras.

NNpe, no proof with graphs , then the audience and buyer have to "believe" ... I amf French, we are Cartesians, I dont accept such proposals.

The same with all that talk about tuning and tone quality, the samples are rare , the spectra analysis nonexistent, and no description of tone is given.

I will agree that the job is usually done by people that are not the best in Maths or physics but when some are prentending to theorize they should give us more material, so the audience can make up his mind without having to pay too much.

That is the way the things are sold that annoy me, most often, I have lost enough time with so called new concepts (I probably also lost my listening ability at some point due to the partial match theory of tuning taken too precisely)

Analysis is a very important part in any concept, but the rules have to be given.

About tone, this is another subject, anything that helps to even tone from note to note is good, not anything that allow to clean the spectra.

That is fun and interesting , as we can see extreme samples in many directions today. All kind of energy preservation and spectra optimisation devices...









Posted by: Roy123

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/15/13 07:24 AM

Originally Posted By: kpembrook
Originally Posted By: Ed McMorrow, RPT
ROY123,
As some level the double blind sort of A to B test you are requiring looks good on paper, and if I were seeking tenure at University would be needed, but to provide practical service to musicians-"I don't need no stinking badges" (To quote the banditos from the movie Treasure of The Sierra Madre).


I would agree. Double-blind tests to disprove the null hypothesis are entirely appropriate for drugs and medical procedures where people's lives are at stake. However, this is not by any means the only way to "know" something. In fact, only a microscopic percentage of all we know comes to us that way. To suggest we won't reliably know something about Ed's development until we exhaust what might well be the entire piano industry's R&D budget for a few years just isn't real.

Certainly it's not appropriate to dismiss or muzzle small innovators when their presentation is well-reasoned and reflects some sort of practical interaction with the real world through direct observation of phenomena. This is NOT to say that there shouldn't be questions and critiques as time goes along. Those are entirely appropriate. But to dismiss something or someone just because they don't have a corporate research budget won't be helpful to consideration of innovation in our morbidly conservative industry.


My comments about double-blind listening tests were informed by the vast body of evidence from psychoacoustics . You may poo-poo it, but the evidence unambiguously shows that human perception of tone quality is incredibly suggestible. We all tend to think, myself included, that we hear what we hear, and that we can't be fooled, but the truth is far different. So, I'll repeat, any listening tests that purport to differentiate sound quality are simply not worth much unless done blind.

[edit] I thought it appropriate to add that double blind tests need not be expensive. For example, a test could consist of 2 pianos behind a curtain with people listening and a third party playing one or the other, or it could be two pianos whose innards are not visible, both of which can be played by various people. There are many ways of doing double-blind testing, and many of them are not expensive.
Posted by: Roy123

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/15/13 07:43 AM

Originally Posted By: Ed McMorrow, RPT


The importance of pivot to the very short treble strings cannot be overstated. The T-mode must be able to flex the portion of string between the V-bar and the duplex rest. Even when you get down to the agraffe section, placing the agraffe side of the string rest felts 10mm or so behind them and using the densest felt produces an audible difference. As does chamfering the agraffe string holes so as to allow the fullest pivot string motion. I have verified all of this with A to B comparisons.


Well, any pivoting across the capo represents T-mode energy that bleeds across--some, or all of which is ultimately lost to heat, and which therefore can detract from sustain. The extent to which the string can pivot over the capo is the extent to which the capo does not terminate the string but instead simply enforces a node in the string at that point. Clearly the string doesn't pivot at the bridge--why is that not a problem?

The chamfering of agraffe holes may improve tone by providing a cleaner termination instead of by providing improved pivoting. Only careful testing, not listening, would be able to discern the difference. You say that the string "must" be able to pivot at the front termination. This is a strong claim, and until you or someone else shows by a well designed test that a non pivoting termination is nonfunctional, I'll have to be skeptical.

If my memory serves me correctly neither the Steingraeber nor the Walter grands use tuned front duplexes. As such, I believe they are designed to minimize or eliminate to the extent possible any energy bleed across the capo. I believe this is a stated design goal of the Walter grands. Are you really suggesting that these two piano companies produce grands with poor sustain and nasal tone in their treble sections?
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/16/13 01:27 AM

Olek,
Accelerometers on the v-bar could tease out L-modes from T-modes but I don't know how to measure the L-mode damping in the duplex segment by the duplex string rests.

I don't think I am as far out there as the "Static electricity" guy. The present state of the art acknowledges L-modes as being significant to piano tone.

To Ando and Olek,
I must admit I have a bit of antipathy to archived qualitative media such as video, pictures or spectra for something as multi-sensory as a musical instrument. I have never been one of those piano guys with all the pretty piano pictures that are supposed to impress my customers about how good my pianos play and sound. I try to have potential customers play examples of my work to judge for themselves.

ROY 123,
Listening tests are significant but very hard to control. Psychoacoustics is a very real discipline and in my early work as a tech I independently coined the term before I knew it was already used.

The evidence from witness memory shows clearly how our memories can be manipulated and I think it is obvious our aural perceptions are subject to that as well. I have always been blessed with an excellent tone memory. I have tested my technical protocols in blind tests and so far no surprises.

It is string stiffness that drives the need for pivot terminations. I have done A to B chamfered /pivot optimized agraffes against stock configurations. The increased warmth, clarity and sustain is obvious.

I have never seen a forward termination that could function as a complete reflexion point except in a piano with a V-bar 0.25" wide and flat! Ugly tone to the Nth power that one was. THIS termination turned struck string motion to heat at the V-bar much more than the flexing of T-modes in the duplex segment. If piano strings were perfectly flexible, and the only restoring force acting upon them was tension, you would be correct about only reflecting terminations.
Posted by: Roy123

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/16/13 07:45 AM

Originally Posted By: Ed McMorrow
It is string stiffness that drives the need for pivot terminations. I have done A to B chamfered /pivot optimized agraffes against stock configurations. The increased warmth, clarity and sustain is obvious.

I have never seen a forward termination that could function as a complete reflexion point except in a piano with a V-bar 0.25" wide and flat! Ugly tone to the Nth power that one was. THIS termination turned struck string motion to heat at the V-bar much more than the flexing of T-modes in the duplex segment. If piano strings were perfectly flexible, and the only restoring force acting upon them was tension, you would be correct about only reflecting terminations.


I don't know--the whole topic seems a bit fuzzy to me. For example, even if we assume that the capo provides a pivot termination, it is certainly highly anisotropic--i.e., the degree to which the string can pivot vertically is different from the degree to which it can pivot horizontally. In the latter case, T-mode vibration of the string would tend to scrub against the capo. I wonder if the anisotropy of the string termination can cause muddy tone or even false beats on occasion.
I also wonder how much pivoting really goes on when you have string angles of 10 to 15 degrees off the capo. It shouldn't be too hard to measure T-mode string vibration before and after the capo--a magnetic pickup mounted close to the bearing point, equidistant from either side might do the trick. It might also be interesting to mount two piano strings in a test fixture that would allow quick comparison of different termination schemes side by side.

Finally, I still wonder, if a non-pivot termination is death to tone, why the bridge as we know is almost universally used. The ordinary offset pins used on the bridge don't provide a pivot termination, and although bridges with agraffes, which could potentially provide a pivot termination, were tried in the past, they were largely abandoned.
Lots to think about; many experiments to try.
Posted by: Withindale

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/16/13 11:48 AM

Originally Posted By: Ed McMorrow, RPT
My apologies to all who cannot access the article. If you send me your mailing addresses I will send a ...

Would it be possible to send a pdf of the article to save time and postage costs?
Posted by: Withindale

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/16/13 11:56 AM

Originally Posted By: Roy123
Finally, I still wonder, if a non-pivot termination is death to tone, why the bridge as we know is almost universally used.

There is one obvious difference between the terminations at the bridge and the capo or agraffe. The purpose of the bridge is to transfer some energy whereas the capo and the agraffes should conserve it.
Posted by: Roy123

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/16/13 12:54 PM

Originally Posted By: Withindale
Originally Posted By: Roy123
Finally, I still wonder, if a non-pivot termination is death to tone, why the bridge as we know is almost universally used.

There is one obvious difference between the terminations at the bridge and the capo or agraffe. The purpose of the bridge is to transfer some energy whereas the capo and the agraffes should conserve it.


Well, the bridge is designed to transfer energy to the soundboard. The bridge is not meant to provide a lossy string termination, which would simply waste string energy as heat.
Posted by: Withindale

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/16/13 01:59 PM

Originally Posted By: Roy123
Originally Posted By: Withindale
Originally Posted By: Roy123
Finally, I still wonder, if a non-pivot termination is death to tone, why the bridge as we know is almost universally used.

There is one obvious difference between the terminations at the bridge and the capo or agraffe. The purpose of the bridge is to transfer some energy whereas the capo and the agraffes should conserve it.

Well, the bridge is designed to transfer energy to the soundboard. The bridge is not meant to provide a lossy string termination, which would simply waste string energy as heat.

I had thought about saying the purpose of the bridge is to transfer some energy at each vibration and conserve as much of the rest as possible (to sustain the note). The slight kinks in the wire at the bridge pins appear to be a simple way of doing that reasonably well.
Posted by: Olek

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/16/13 02:42 PM

May be the duplex is just there to slow /filter the returning waves on the little part of the sounding lseght (between hammer and capo/agrafe)

Whaj/t I seem to hear is an advantage at the moment of attack, then indeed it also create all sort of high pitches that blend in the "normal tone"
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/19/13 02:03 AM

ROY 123,
String termination anisotropy most definitely contributes to string falseness-If the string path over the pivot is sideways even slightly-the duplex segment and struck segments will influence horizontal displacements, H-mode). The string stiffness lets the segments "disclose" each others position and this will induce H-mode. The effective string lengths are different for H-mode and Vertical mode.

Bridge agraffes have always produced L-mode because of the rocking bridge T-modes. They make metallic whines that sound sort of like T-mode beats. They also are heavy. The bridge is the string termination that is supposed to damp the string by coupling it to the air. Voila, tone appears!
Posted by: Roy123

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/19/13 01:43 PM

Originally Posted By: Ed McMorrow, RPT
ROY 123,
String termination anisotropy most definitely contributes to string falseness-If the string path over the pivot is sideways even slightly-the duplex segment and struck segments will influence horizontal displacements, H-mode). The string stiffness lets the segments "disclose" each others position and this will induce H-mode. The effective string lengths are different for H-mode and Vertical mode.

Bridge agraffes have always produced L-mode because of the rocking bridge T-modes. They make metallic whines that sound sort of like T-mode beats. They also are heavy. The bridge is the string termination that is supposed to damp the string by coupling it to the air. Voila, tone appears!


It would be interesting to know if the more modern bridge terminations, like those used by Steingraeber Phoenix and Stuart & Sons suffer from those problems.

Even if the string is not at an angle as it goes under the capo, there should still be anisotropy, as the capo is anisotropic, i.e., it is roughly circular or parabolic along the string axis, and linear normal to it. The shape of the capo, as well as the string angle and details of the termination beyond the capo, may tend to favor horizontal or vertical T modes. Any system will tend to go into a minimum energy-dissipation configuration. For a piano, I think that in general that would favor horizontal vibrations.
Posted by: Larry Buck

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/19/13 03:20 PM

Ed,

Where are you with your patent?

If you have filed, it should be OK to post some specifics of your design here. We would have an opportunity to review more authentically.
Posted by: Larry Buck

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/21/13 04:12 PM

Ed,

At the least, perhaps you will let us know when your patent is filed and available to the public.

I look forward downloading a copy and reading it.

I hope you will be available here to answer questions about the specifics.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/21/13 11:35 PM

I am working on getting my website up and first on the site will be a version of the article with some more pictures. Once up I can link from pianoworld.

Larry,
The patent application is filed with 44 claims. It awaits the claim review process which can take up to two years. Now with the sequester maybe more. The US patent office actually returns a profit to the general fund.

I don't want to debate claims anywhere else but with all the interested parties that show up during the review process.

Are you interested in licensing the technology?

Roy123,
Have you heard a Phoenix or Stuart agraffe bridge? Or a Sohmer or Paulello?

I shape my capo bar profiles to a definite V. Have done so for over 25 years. If the string path is straight across the V-bar up to the tuning pin very little H-mode is induced there. At the bridge is another thing because of side stagger. However the reflections from the pivot capo helps push the string back towards V-mode T-modes. V-mode provides a more and quicker onset for unison coupling at the bridge.
Posted by: Larry Buck

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/22/13 10:36 AM

Good Morning Ed,

At the very least, I am interested in reading it.

It is best to hear a piano "in person", although until I can do that, as some have mentioned, I would also like to hear a recording of one of your pianos.

It is certainly easier to discuss the attributes of your claims from the advantage of having heard one of your pianos.

You might consider sharing some of your testing methods and some of your formulas and computations. For example, how you measure, record or otherwise compute things like Longitudinal modes specific to the front scale.

I have a 212 Phoenix Steingraeber here in Lowell. Many have seen it including Roy123.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/22/13 11:12 AM

Larry,
I have not measured L-mode in my work. The evidence for it is based on the placement of duplex rests that are soft enough to damp L-mode and not damp T-mode. Placing those in a piano removes the high whistles many notes of a duplex scale have. I don't think any other explanation is possible than controlling L-modes.

I am very pragmatic in my work. I use the known physics to frame postulates and then do A to B tests.
Posted by: Roy123

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/22/13 12:16 PM

Originally Posted By: Ed McMorrow, RPT

Roy123,
Have you heard a Phoenix or Stuart agraffe bridge? Or a Sohmer or Paulello?


As Larry mentioned, I've played the Phoenix at his shop and didn't notice any undesirable sounds.
Posted by: jim ialeggio

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/22/13 02:06 PM

Originally Posted By: Roy123
As Larry mentioned, I've played the Phoenix at his shop and didn't notice any undesirable sounds.

But to be fair, that piano did have some duplex sounds/noise. Which of those words one chose to use would depend on how one wanted to view those sounds aesthetically. Larry was able to massage the duplex conditions to quiet the sound/noise to suite American aesthetic tastes.

In a piano with that many new systems, it would be hard to pinpoint what sound/noise was caused by what system.

I look forward to playing that piano at Larry's Piano World party tomorrow. Any chance you'll be there Roy?

Jim Ialeggio
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 03/26/13 12:23 AM

ROY123,
You described the flexing of the duplex string segment across the pivot termination as wasting energy carried by the struck string segment. The opposite occurs-the flexing of the duplex segment is not wasted energy, it returns energy to the struck string segment as it returns from its displacement. And as long as the duplex T-mode is distant enough from the T-modes of the struck string-almost none of the duplex movement is coupled to the air. Flexing alone of the stiff piano string at the forward termination wastes more energy heating up the wire at that point than a pivot.

The pivot termination greatly helps with making the fundamental stronger. And in the treble the fundamental is KING.

One of the most important parts of a FTDS scale is that the pivot termination conditions are blended and proportioned across the compass in a way never before accomplished. This helps with producing a more even and full tone quality.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 08/21/13 12:34 AM

For those that are interested, the FTDS patent application can be viewed online at www.freepatentsonline.com/y2013/html
Posted by: BDB

Re: "Fully Tempered Duplex Scale" Tech article coming March - 08/21/13 12:49 AM

That link does not get to the patent, but a search brings it up.

I have given it a quick perusal, but I am not clear what exactly is being patented, nor what the advantages are supposed to be.

I would still appreciate a recording. I am reminded of the person who visits a shrine at which hundreds of crutches have been left by people who believed that they were cured by prayer at the site. The person also sees a piece of paper that says, "One artificial limb would be sufficient!"
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 08/21/13 01:02 AM

Sorry I didn't make it a link, I don't know how. PW assumed I linked it by editing in the underline.

The advantages have been explained in my previous posts. I have solved the duplex noise issue some notes of the prior art always exhibit.
Posted by: Withindale

Re: "Fully Tempered Duplex Scale" Tech article coming March - 08/21/13 02:31 AM

Originally Posted By: Ed McMorrow, RPT
Sorry I didn't make it a link, I don't know how.

http://www.freepatentsonline.com/y2013/0205968.html
http://www.freepatentsonline.com/20130205968.pdf
Posted by: BDB

Re: "Fully Tempered Duplex Scale" Tech article coming March - 08/21/13 02:39 AM

This is the link to the actual patent.

Quote:
The advantages have been explained in my previous posts. I have solved the duplex noise issue some notes of the prior art always exhibit.


I am not clear on what the "duplex noise issue" is. As I said, a recording that shows it would be nice. Not knowing what it is, I could not say whether you have solved it or not.

Most problems that seem to be related to duplex scales (or more accurately, the portions of the strings beyond the speaking length) I have found to be due to tuning issues. Some of them are voicing. These are problems pointed out when someone puts something in to mute off that portion of the string. When I pull the mute out, there is usually no difference, or it is something I can improve by tuning or voicing.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 08/23/13 01:30 PM

BDB,
On every trip to the soon to be closed basement at Steinway Hall in NY-I have seen C&A pianos with felt stuffed into the duplex behind the capo bar. They must be hearing something that they don't want ringing. You said you don't usually notice a problem when you remove the felts and if you do-tuning and voicing fixes it. Troublesome duplex noises are commonly known in the industry. That is the problem I solved.

Problem duplex noises can be reduced by tuning/phasing unison strings/needle voicing/hammer shaping-but these things just mask the problem.

(I would also like to thank you for granting my patent-since your post included "This is the link to the actual patent"-I know you are influential BDB-but I never knew your duties included Patent Examiner") CHEERS

I welcome you to judge for yourself if you can find your way to my shop in Mukilteo, WA. And while you are at it bring your recording equipment and we can make a recording and post it if you like.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 09/19/13 12:03 AM

I wanted to bring this topic back because today I tuned two 1990's Steinway B's that I regularly maintain and I think the comparison between them may illuminate this topic some more.

Both B's have been completely tone regulated by me some years ago. One B has a capo bar so hard it cannot be reshaped. The other B's capo was reshaped and is soft. (By reshaped I mean brought to a definite V at the string contact point-no radius other than that which the string works into it.)

The treble of the hardened B is ringing like metal. Echoey, chiming, sizzling sounds arise with every note in the capo section. Also, some duplexes are very close to unison with T-modes of the speaking lengths-those notes are the most disagreeable. In contrast, the agraffe section sounds warm and rich.

The other B has a relatively even warmth across the compass. It sounds thrilling when pushed and can whisper with the best of them.

The only significant difference between them is the hard capo. The extraneous, ugly treble sounds from the hard capo are not all just extra strong T-modes. You can hear the pulsing of very fast beats. These beats do not go away when the T-modes of the unison is tuned.

My contention that L-modes can produce audible beats is the only explanation that can be found.
Posted by: Gary Fowler

Re: "Fully Tempered Duplex Scale" Tech article coming March - 09/19/13 10:32 PM

Ed, congrats on your deplex scale innovation. I only tune and service pianos, but I appreciate someone who makes the instrument BETTER!
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 09/19/13 11:40 PM

Thank you Gary for the kind words. If you ever are in the Seattle area please try to find the time to visit my shop. I would very much enjoy showing you my pianos.

It is difficult to innovate in such a mature industry such as the piano. But the mystery of what contributes to making an instrument with a great capacity for musical expression is one that intrigues me. When I was young and just starting piano work, I kept looking for some old guy who knew all the elements. I felt sure there had to be someone who understood the physics and engineering. When events evolved that staying in university was no longer necessary to avoid going to Vietnam-I dropped out thinking that "I'll get this piano thing figured out and then I will go back to finish my chemistry degree."

I never found that "old guy" until recently-I looked in the mirror and I was OLD! But I still don't have all the questions answered-and maybe don't even know all the best questions to ask! And I still don't have a degree.
Posted by: Phil D

Re: "Fully Tempered Duplex Scale" Tech article coming March - 09/20/13 10:05 AM

Ed...

Please...

Get this invention recorded properly. It will be worth it. We're all so excited to hear it. Pretty please?
Posted by: LeeSumner

Re: "Fully Tempered Duplex Scale" Tech article coming March - 12/11/13 11:23 AM

Yesterday a colleague and I were able to check out Ed's freshly remanufactured M&H BB (1970s vintage) which features his FTDS design. This instrument was purchased from Prossers in June of this year for a neighborhood high school performance venue. Prior to that it had received no reconditioning excepting hammer reshaping and periodic regulation. Given Ed's extensive handiwork,(new block, rescaled lower tenor and bass section(Mapes custom made strings with stainless steel wound tri-chords at the tenor/bass break), WNG shanks,Ronsen hammers, key rebalancing, reconfigured bridge thicknesses and other modifications best explained by Ed, I can't say to what extent the FTDS alone is responsible for its substantially improved clarity, power, and sustain in the last two octaves consistent with Ed's claims. I can say that in its unrestored state, from C5 up the treble displayed the problems Ed has enumerated as does the 1971 Mason A we're about to rebuild which has resisted conventional hammer mating/voicing and string leveling remedies. At the very least his FTDS which includes meticulous reshaping of the V-bar, height/alignment of agraffes and counterbearing angle adjustments has effectively eliminated any sizzles, snare drum/buzzes noises. In combination with optimizing strike point and his choice of Ronsen hammers, the tails of which he aggressively tapers to around 5 or 6 mm in the high treble (possible with WNG shanks) to lower mass, I suspect the FTDS contributes in large part to the greatly improved sustain, power, singing quality and color in the upper register. Over a range of dynamic levels the piano's tone was even, full-bodied and orchestral sounding without ever becoming strident even at fff. All in all a marvelous piano now. I will be visiting the music director at the H.S and may have more to report in a later post.
Posted by: Withindale

Re: "Fully Tempered Duplex Scale" Tech article coming March - 11/19/14 08:17 AM

Ed, I hope this is the thread you asked us to revive.

I would like to ask about longitudinal modes and the reduction in energy loss mentioned in the quote below.

Two points: first, do you find that an increase in sustain tends to go hand in hand with a reduction in the sound level of longitudinal modes? Second, have you thought about the energy transfer mechanism at the capo bar, specifically at the surface of the string in contact with the bar where it has "machined" its groove?

Quote:
If I understand you correctly, you are attempting to clean up the tone by filtering out unwanted noise and prevent energy loss.

Below is a picture of an A.B.Chase upright in which they were after the same thing a hundred years ago. As you can see, the figuration is different than yours, but certainly accomplishes the same thing. Isn't the "wooden filter" below the metal rod do the same thing your trying to do. The tone on this upright is amazing by the way.

Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 11/19/14 10:35 AM

Withindale,
Thanks for the questions. I think most of the increased sustain is due to more effective pivot termination-but I haven't tried to separate that out from changes in L-mode energy-and don't really see how I could.

As regards the capo bar-I have done work with temporary modifications to increase horizontal stiffness. I have also experimented with temporary attachment of damping material to it. Many capos are way too flexible out in the middle of the section and this increases hammer knock noise and "wobbles" the vibrating string. This increases the duplex hiss. I am working on a piano now that has a much stiffer V-bar horizontally so when completed that will provide more evidence.
Posted by: Withindale

Re: "Fully Tempered Duplex Scale" Tech article coming March - 11/19/14 11:54 AM

Ed
I was trying to test the hypothesis that a more effective pivot termination not only increases sustain but also reduces the amount of vibrational energy dissipated as L-mode sound at each reflection. That's based on the idea that a less effective termination will restrict the flow of longitudinal waves along the string, generating L-mode sound and noise.

Thanks for the tip about hammer knock noise and "wobbles" in the middle of a capo section, something to check.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 11/19/14 11:02 PM

L-mode can pass right over the V-bar. And since all three unison strings are ever so slightly unequal in speaking length and the same with the duplex rests-6 different fundamental L-modes can be carried by a unison. These frequency differences can create audible beats. Even though the frequency of the L-modes are above audible range.

The T-modes in the duplex unison can also beat with each other and when the L-mode beats meet the T-mode beats there is a whole lotta sizzling going on. Some of this noise is quite short lived as the L-modes are damped by the bridge. But when you add in capo flexing and bridge rocking another set of L-mode excitation sources start up.
Posted by: bkw58

Re: "Fully Tempered Duplex Scale" Tech article coming March - 11/20/14 08:23 AM

Originally Posted By: Ed McMorrow, RPT

On every trip to the soon to be closed basement at Steinway Hall in NY-I have seen C&A pianos with felt stuffed into the duplex behind the capo bar. They must be hearing something that they don't want ringing. You said you don't usually notice a problem when you remove the felts and if you do-tuning and voicing fixes it. Troublesome duplex noises are commonly known in the industry. That is the problem I solved.

Problem duplex noises can be reduced by tuning/phasing unison strings/needle voicing/hammer shaping-but these things just mask the problem. ..


My one NY-minute trip through that basement didn't reveal this but I don't doubt it. Have both seen (and used) these masking techniques in numerous pianos - C&A and others - over the years. The occasional confused look I'd get when explaining to client that "the little piece of felt you see is not a mistake - please do not remove" is still a fresh memory. Thanks for solving the problem.
Posted by: OperaTenor

Re: "Fully Tempered Duplex Scale" Tech article coming March - 11/20/14 12:17 PM

Is it possible to post the new link to the PTG article? The old one is broken.
Posted by: havier

Re: "Fully Tempered Duplex Scale" Tech article coming March - 11/20/14 12:23 PM

Originally Posted By: Ed McMorrow, RPT
When events evolved that staying in university was no longer necessary to avoid going to Vietnam-I dropped out.....


Ed,
I wish you much success with your invention, but honestly, I was deeply saddened by your comment above.
I wish to take this precious moment to thank all of the Veterans who put their lives on the line for us to have the freedom to work on and enjoy the piano.
Posted by: prout

Re: "Fully Tempered Duplex Scale" Tech article coming March - 11/20/14 03:16 PM

Originally Posted By: havier
Originally Posted By: Ed McMorrow, RPT
When events evolved that staying in university was no longer necessary to avoid going to Vietnam-I dropped out.....


Ed,
I wish you much success with your invention, but honestly, I was deeply saddened by your comment above.
I wish to take this precious moment to thank all of the Veterans who put their lives on the line for us to have the freedom to work on and enjoy the piano.


Ed was making a statement germane to the conversation, not espousing his personal beliefs.

Your comment has no place in a piano forum. Go to a political forum if you feel the need to discuss politics.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 11/20/14 09:32 PM

Perhaps you are having some trouble with reading comprehension if you come to the conclusion that I said anything in the post you referred to or in any other PW post I have ever made that denigrates U.S. military service.
Posted by: Ed McMorrow, RPT

Re: "Fully Tempered Duplex Scale" Tech article coming March - 11/23/14 08:58 PM

For those who have doubts that longitudinal modes affect treble tone I have a very recent quote from Richard Dain of Hurstwood Studios regarding the bridge agraffes on the Phoenix Piano. The quote was provided by MiguelAngel07 who PM'd me citing what Mr. Dain recently communicated to him.

"Originally we used our bridge agraffes over the whole compass of the Phoenix piano's, but tests showed they encouraged longitudinal beat frequencies in the upper registers which some people found undesirable. We now use a pin bridge in these registers so the longitudinal frequencies are suppressed by friction of the string on the bridge top as in traditional pianos".
Posted by: jim ialeggio

Re: "Fully Tempered Duplex Scale" Tech article coming March - 11/24/14 10:24 PM

It would be interesting to know how Dain quantified the appearance of the L modes up there. Do we have any info on this?

Jim Ialeggio
Posted by: Withindale

Re: "Fully Tempered Duplex Scale" Tech article coming March - 11/26/14 06:12 PM

Jim, I do not know what Richard Dain did but maybe he compared the same strings in a piano, or a rig, first with bridge agraffes then pins. Frequency analysis and aural assessment could do the rest.

My hunch is that it is correct to say the bridge agraffes encouraged longitudinal beat frequencies, but I am not so sure the top of the bridge suppresses longitudinal frequencies.

The rationale is the agraffe presents more of a rigid termination to longitudinal waves and so reflects them. Pins do not offer much of an obstacle to longitudinal waves so they tend to carry on to be reflected at the hitch pin.

Please discuss.
Posted by: jim ialeggio

Re: "Fully Tempered Duplex Scale" Tech article coming March - 12/11/14 10:26 PM

I've just finished 2 pianos, both complete re-manufactures, both of which include the FTDS technology. A 6'-6" Chickering 123 (1908) and a 5'4" Chickering 135 (1923).

I figured I'd post some sound samples...keep in mind, I'm working the learning curve with the implementation of Ed's treble termination ideas. The 123 (6'6") was the first, and I struggled with the layout and plate grinding angles for the copolymer on the 123. I started to get more of the hang of setting up the duplex by the 2nd piano.

Knowing what I know now, the Chickering 123 was really not a good candidate for this technology, because the alto (1st treble section note 49-68) does not have a capo bar. This technlogy really requires the stiffness of a capo bar, and the 123's agraffes throughout this alto section are simply too flexible, in my opinion, to make effective use of the active duplex. The 2nd piano, the 135 has two true capo sections, so I think it was a better choice, regarding the FTDS.

Anyway, here are 2 sound samples from each piano...just straight up, me playing, one take, no messing with the sound file. I did fade out Summertime...uh...it kind of lost the thread, if you know what I mean, so I cut it short.

Chickering 123

Tenderly Jim Ialeggio Chickering 123 6'6"

Summertime Jim Ialeggio Chickering 123 6'6"

Chickering 135

some compass wide noodling and Pinky JIm Ialeggio Chick 135e n

Bach 2 part invention #5 dry-no sustain pedal Jim Ialeggio Chick 135
Posted by: Grandpianoman

Re: "Fully Tempered Duplex Scale" Tech article coming March - 12/12/14 05:37 PM

Nice sounding pianos Jim! Like the tuning....and your noodling as well. smile

Both have a very even, singing sound.

What you are doing seems to enhance the tone, sustain, and overall bloom/sustain of both pianos!