Independents

Hi all,

I wonder if this has been discussed before, but would just like to confirm, it seems to be stated that the Chronometre Resonance from F.P. Journe is the ONLY wristwatch that utilises the Resonance phenomenon, but what about the Duality from Philippe Dufour?The layout looks pretty similar especially with both balance wheels so close to each other, but as it is rather difficult to find out more concrete information on the Dufour, i was hoping if anyone here, especially if you are an Owner, to chime in on this topic.

Or is the Duality , despite having the balances close to each other, NOT exploiting the Resonance phenomenon as the balance wheel are further apart than they are in the CR.

Cheers

Stephen

...and probably from others who are better schooled than I, but the big difference (no pun intended) is that in the Duality, the two balances are connected by a differential (as in a car) to average out variations in the rate of the two escapements.

It may be apocryphal, but I've heard a quote attributed to Mr. Dufour when asked about the Resonance: "it's a nice watch, but he left out a few parts!"

Best,

Gary G

Hey Gary!

I know you would chime in on this! Ok, yes i read about the differential part before, which i guess is missing in the Journe.

But in this case, it does seem to be that the Duality do NOT utilise the resonance phenomenon!

Not that that is a bad thing, as my recent encounter with a Platinum Simplicity quite literally blow me off.

In a good way.

Stephen

Would like to know the intention of Mr. Dufour for mentioning this sentence.

Add to the controversy of the Journe Ressonance. Mr. Papi of Renold et Papi have this comment of the Ressonance. "I know it works, the ressonance in the watch."

I'm waiting for more people of experience to clue in with the details.

This will be interesting ...

Regards
Tyler

There is a mechanical coupling in the Duality of Mr Dufour, there is no mechanical coupling in the "Resonance" of Mr Journe.

Talking with some people, it seems that it is not a "Resonance" wich is a specific physical phenomena, but the coupling found without mechanical part is very elegant and "magical" indeed, I love it. If I understand more or less why Duality is theoretically more precise, for Journe it is still a bit dark in my mind why it is more precise theoretically. Let's say that there is a part of "mystery" in Journe Resonnance , like often with him...

Two fabulous watch and the "synchronisation" button for the Journe, is quite fun and playful.

cheers

Francois

they are physically completely different. The duality averages two balances that are not in sync through the differential; in the Resonance, they are in synchrony.  To call that "Resonance" is in my view not exactly correct because resonance means inducing movement in an oscillator that was not previously in motion; what happens in the Resonance is that two oscillators that are very carefully regulated to be as similar in frequency behavior as possible are synchronized through a coupling tnat is not through a direct mechanical link but through baseplate vibration/air flow around the balances/some other magic.

If we agree to call the prinicple of coupled oscillators that are synchronized "Resonance", then the other watch that does this that I know of is the Haldimann H2; there, however, the two balances are mechanically coupled.

 

Best

Andreas

and I don't think that Dufour claims that the Duality is a "resonance" watch.
Technically a resonance timekeeper should be called a timekeeper with coupled oscillators, resonance is the phenominon describing the increase in amplitude when two coupled oscillators are tuned at or near the same frequency.

There are many possibilities to couple two oscillators, Journe uses he movement of air around the balance wheels, Haldimann couples the two oscillators in the H2 through a slight movement of the hairspring studs.
It is interesting that Beat got the idea of coupling through the fixed end of the hairsprings in analogy to the way resonance pendulum clocks work.  There the coupling is through a very slight movement of the block holding the 2 pendulums.

For a deeper look into the Duality be sure to see Ron De Cortes article on the Duality on the PuristS.
www.network54.com

This is a fascinating subject that I will be looking into in more detail in the future.
Don

If I understood well, the statistic error is divided on the Duality with the coupling.

But for the Resonance is it also the same? The theoretical precision advantage is not clear in my mind, I love her "magic" and the "playful" side of it, but the theory is missing.

As the air coupling is damped Is it right to suppose the damping could lower the statistic error? Without it, the error is directly transmitted I suppose and then I don't see the where is the advantage.

All of this is quite theoretical, in reality both must be quite complex to adjust to make them precise.

Sorry for those bored by the theory part.

cheers

Francois

but what has remained tells me that resonance effectively increases the Q (damping factor) of the coupled oscillators compared to a single oscillator.  Increasing the Q reduces the energy needed , but more importantly for timekeeping also also reduces the bandwidth, the width of the Gauss curve describing the actual cycle to cycle oscillation variation -> it follows that the coupled oscillator must be more stable.
The big difference between a balance and hairspring oscillator and a quartz oscillator, for example, is the much higher Q of the quartz (the Q of a quartz oscillator is  ~10000, of a balance and hairspring oscillaor ~240 if I remember correctly)  which makes the quartz much more accurate over time. 
If using coupled resonators can increase the Q significantly maybe it can significantly better the accuracy of a balance and hairspring watch (maybe it is better to say a 2 balance and 2 hairspring watch).  I am planning on trying it out in the next year or so. 
The other question is if it will be possible to regulate the watch to +-0 or if that will be such a problem that we will end up with a ships cronometer calculation to know the real time.
In any case I think it is worth a try.
Don

It makes it more clear in my mind, and good luck for your experiments to regulate adjust both mechanism with the same characteristics !
These kind of watches are fascinating.

cheers

Francois

Hi Don,

My studies are as long ago as yours

The Q of quart is much higher - in the 10^6 to 10^9 range, if I remember.

I'm sure there's a (pedantic) terminology point to make:  driven oscillators synchronise, they don't resonate.  Resonance is where an undriven system starts oscillating due to energy transfer from a driven oscillator.  The classic horlogery example is the weight in the pendulum clock that starts to oscillate in time with the pendulum when it reaches a certain length.

I'm still not clear of the advantage of higher Q. It protects the oscillator from being forced off frequency by external frequencies (vibration) not one-off impulses or shocks, and it's not clear to me what the vibrations are in a watch that high Q protects against.  There seems to be a rule that the more stable the system the higher the Q, but it's not clear (to me at least) that the higher Q has caused the stability.

Not sure I can face reading the debates in the HJ, NAWCC etc again

nick

If I understood well, the statistic error is divided on the Duality with the coupling.

But for the Resonance is it also the same? The theoretical precision advantage is not clear in my mind, I love her "magic" and the "playful" side of it, but the theory is missing.

As the air coupling is damped Is it right to suppose the damping could lower the statistic error? Without it, the error is directly transmitted I suppose and then I don't see the where is the advantage.

All of this is quite theoretical, in reality both must be quite complex to adjust to make them precise.

Sorry for those bored by the theory part.

cheers

Francois

with two days differences... I even don't know how I did that.

sorry dear moderators

Francois

The search function is not great, but it does work and will find lots of fascinating threads on both watches.

_john

And it is easy to understand why: with such distance, how can they be in "resonance"?



Moreover, the concept of resonance in a wristwatch is very theorical. If 2 or 3 seconds per day both regulating organs are "in resonance", it is a miracle.

The Duality concept is closer to the double spiral one from Moser or MCT, its objective is to compensate and so its purpose is similar to the Tourbillon.

That's my point of view!

Fx

... you learn something everyday

Thanks, FX.

Ken

From different angle:

FX, two oscillators can be synchronized with the distance, you just need a mobile and thin structure to transmit the oscillations without damping them. This is an example
www.youtube.com

My impressions ( no certainties here)

Bridges of a watch are not mobile or "thin" enough for this purpose, and I won't call it "resonance" for this reason.
And that's why there is no resonance in Duality.

As it is transmitted thourgh air in Mr Journe resonance, you need a very thin "air structure" (with boundary layers effect) , otherwise your oscillations are not transmitted from one oscillator to the other. That's why I find the way without mechanical pieces very elegant and magical.

In the end both resonators are coupled so I suppose it does make an effect close to a normal resonance.
But adjusting two oscillators with exactly the same characteristics is really difficult.

At thanks to all people who helped me to have some clues about it. (Tic et Tac , Randallboggs, Anteus from different horlogical forums)

Francois

because I am pretty sure that the balances stay in synchrony for weeks. If you listen to it, or put it on a time balance, and I even made a high-speed video of it once... it is pretty clear that the balance wheels and escapements move in lockstep. If you shake it, it takes a few beats and they are in synchrony again ... I am still not sure how it works exactly but that it works, to me, is hard to deny?

 

Best

Andreas

While the Duality might offer superior chronometry by averaging out the inconsistencies in the two escapements, the Resonance keeps the two escapements in harmony, and that is obvious to the naked eye. So both 'halves' of the time display are synchronised and you can set the second time display to whatever you want. Completely different approaches in my mind, and not to be compared. it's just a coincidence that the Duality and Resonance have two balance wheels and escapements!

Andrew

without mechanics or mechanical solid structure link like the youtube example. The synchronization works, I saw it too, I find that beautiful, and brilliant! Just uses air boundary layers effect between the two balance wheel imho. Again, I have no certainties, it is just my vision of it, I may be completely wrong.

Agreed with Andrews, not the same aim exactly, one is for pure chronometric performance, the other synchronizes two mechanism, with , I suppose, a chronometric effect, reading Don explanation.

cheers

Francois

Hi all,
not sure the old warchrap archives are still accesible (I guess they aren't) - but the Journe resonance was discussed quite extensively years ago.

The problem with this watch is - no data at all......at least not that I'd know (doesn't mean that much).
The basic difference compared to the duality is explained by some others already.
I miss mention of the Haldimann though - probably less mystique, but synchronizing of the two balance wheels through coupling of the hairspring studs (with an additional spring element) makes much sense and does indeed work, IMO.

I'm compltely in awe reading about all this miracles - i.e. those who are capable of actually beeing able to catch this perfect working synchronization "by the naked eye".
Wow, I knew I'm getting older, but even 10 years ago I'm pretty sure I couldn't....
The timing machine effect isn't that impressive to me - the built in filter simply picks one signal at a certain point - it's not designed to time two overlaying signals (to the best of my knowledge).

Personally I don't believe the Journe Resonance works, at least  in a technical sense.
One should also keep in mind, if  the system would indeed synchonize, both seconds readings (hands)  would stay visually perfectly in synch.  Those I've seen in the metall. usually tended to be a few seconds off after a day or so. Technically it's already "off" when one beat off , which would be a fraction of a second only....

As a sidenote to those who believe in the "air/laminar flow coupling theory,  if memory doesn't fail, Mr. Journe himself claimed that synchronization doesn't have to do with aerodynamic coupling, even in a vacuum it would perfectly synchronize.

To me the Resonance falls in a similar category as the Centigraphe (or lets say "About-aCenti-Graphe"

Don't take me wrong - I actiually like most fo Journes creations quite a lot .

Best regards
Suitbert

...others said the contrary, that it doesn't synchronize in vacuum.  That's why I believe to this "aerodynamic theory", there are other possible explanations.

What is sure is that I have also seen the balance synchronizing with the naked eye. You stop one of the balance wheel (with a pencil for exemple), and you let it go, and after some seconds/minute it will be completely sychronized to the other balance. I wish you can see that because that is what is "magical" in this watch.

This watch is what you want to believe... or not   , a "faith" watch

If I really love the "Resonance" even if not fully efficient,  I do not like the centigraphe at all...

When you say synchronised, what do you mean?  I believe this normally means same amplitude and frequency but 180 degrees out of phase, and stable over time like this.  How is the phase difference being measured over time to prove the synchronisation?   If they're drifting slightly over time, the I'm not sure there's synchronisation.

Pendulums normally take a very long period to synchronise, and even given the much higher frequency I'm dubious about it taking place in seconds on a watch.

If we're just talking about two identical oscillators with nominally identical frequency appearing to be running "the same", then that's not proven synchronisation.

Personally, by eye, I have difficulty judging the exact end point of a swing: comparing two at once strikes me as nigh on impossible.

As Suitbert says, there's no data.  It would be the work of an afternoon to set up an experiment that proved it with hard data: a couple of thousand dollars will buy a MicroSet and an amplitude detector per balance (a splash in the ocean for these companies, even if they don't already have better equipment), and then a few hours of  experiment, and Hey Presto!...hard data.

nick

... reading that someone had stuck the Resonance on a machine and watched the two "beats" come together to form the one pattern.  I'm not sure what they were testing so I'm not sure what it proves (yes, sorry) but I'm sure they will chip in if s/he sees this thread and is minded.

Written by " Anthony G. Randall, Master watch and clock maker " something of a guru himself!

Thanks for posting.  I remember the article now. 

nick

Nt

-same amplitude

-same frequency but 180 degrees out of phase

-stable over time like this

 

The experiment was both were running like that, one balance wheel is stopped, then released. After... let's say  2 minutes , more? (don't remember exactly) , the two balance wheel were running again with

-same amplitude

-same frequency with 180 degress out of phase

-stable over time.

My eyes are not as precise for sure, but you can see the progressive synchronisation (like the metronome in the example above). I am not alone to have seen this. That is the only thing I am sure about.

cheers

Francois

....two single balance movements - nice slow 18000bph ones with a big balance wheel for easy observation - and placed them next to each other....what would be the difference to the stop/start/synch observation you made?

I would wager it's pretty hard to observe any difference in bph with the naked eye.

Hello All,