Low Frequency :Answering the Question of Why the Top Watchmakers use Frequencies of 3Hz or less

In looking at the best watches I own, I noticed that most of them were running at a frequency of 3Hz (21,600 vph) or less. Not only were famous watches by Philippe Dufour and Roger Smith running at these frequencies, so too were the movements made by F.P. Journe, Kari Voutilainen, Laurent Ferrier, Marco Lang, and Jean-Marc Wiederrecht. Since the most common frequency is 4Hz, why would the top watchmakers opt for 3Hz (21,600 vph) and 2.5Hz (18,000 vph)? At the 2018 WatchTime Show, I asked some of these storied talents that question and got the answers from the watchmakers themselves.

[@rayzhang7591]

I'm so happy that a question randomly popped into my head and let me rediscover your channel. Great video, and great to hear from these legendary people.

[@watchartsci]

Happy to know that WatchArtSci is discoverable by random thoughts, Ray! Take care, Bill

[@blueshirtbuddah1665]

Yet again another awesome video from an awesome event. Thank you so much for doing what you do Bill. Your collection is amazing and your videos are most informative. See you Sunday.

[@watchartsci]

Hi Bruce, that was fun! After the show did you give any more thought to what kind of what you might want? Kindest regards, Bill

[@blueshirtbuddah1665]

WatchArtSci I’m leaning heavily towards getting a Reverso Grand Talle.

[@watchartsci]

Bruce that sounds like a great choice! Let us know if you get it! Cheers, Bill

[@johncherry1870]

I’m at the kindergarten stage of watch nerd and this has me rethinking everything I thought I knew.

[@watchartsci]

No problem John ... we all play in the same sandbox. Cheers, Bill

[@richardteevan4480]

Ryan Schmidt did a quill and pad article that is very detailed on the subject and dispels the myths associated with both lower and higher hertz. There is no right or wrong. The longer reserve, classical watches back to Pocket watches were lower hertz, less complexity, more space in the movement for visual appeal, and the tradition is still rpevelent amongst independent watchmakers. Zenith and Grand seiko lead the 36VPH but also have great technologies and complexity that goes into making the higher beat movements not require more maintenance. PArts materials and new technology offsets the lubriction and increased pounding it takes. People need to understand the escapement parts play a big role in accuracy too so a higher VPH does not mean more accurate than a lower vph if the escapements are not the same. off to the wind up watch show in nyc today (thru the weekend i think today only for me )

[@watchartsci]

Hi Richard, winding up today? I didn't know there was more show?! I think that Ryan is asking and answering a different question than I. I'm not sure he dispelled anything as far as the observation that the top watchmakers use the 18,000 vph. Not a lot to dispel there...and this keeps circling back to the fact that while the "standard" is 28,800 vph, these top watchmakers use 18,000-for the most part. Why? That was the question, and it's not the one Ryan was addressing. Check out this link Kevin sent me: kzbin.info/www/bejne/pKOcgXd8drWdbsU starting around 19:20 of Roger Smith's talk. His comment, in the section Fast Beat, "....."a faster beat hides inefficiency in design"... hints at what I suspected. His designs are elegantly simple as are Marco Lang's in Caliber VI....the trigonal bridge allows the owner to see what's going on and at the same time speaks to the simplicity of the movement. Anyway, it's something we can entertain ourselves with...and will perhaps be a mystery that will lead to a better understanding of what goes on in a mechanical movement. Cheers, Bill

[@richardteevan4480]

@@watchartsci yes a micro show biggest ones are Stowa and Oris, Bunch other smaller micros, met the owner of Zelos, Elshan Tang, so young and his watches are unique. Bought 3 Stowas for my 2 Daughters and a boyfriend for Christmas. The Worn & Wound watch show "Wind Up" is held in Chelsea Mkt (had a great quick braut and German beer for lunch yum) which has a great number of food places and stuff will post some pics in the group.

[@nssomething8370]

Great video Bill. It's interesting to have someone go up to these reps and not ask the usual questions that are always asked. Very interesting.

[@watchartsci]

Hi NSomething, thanks man! It just took some cheeky punter to ask ... my background in research often required getting to the heart of a matter by addressing a question directly. At first they seemed nervous because it's a reply I doubt they had rehearsed for as you said, "...not .. the usual question." However, once they got going, I think they did a great job. Cheers, Bill

[@jesperhvid9667]

Wonderful to hear from these extremely talented people who dedicated so much of their lives to what so few people will experience

[@watchartsci]

They were really cool, too Jesper. Take care and stay safe, Bill 😷

[@oscargustavoarcosruiz8793]

A very educational video, as usual. Mission accomplished.

[@watchartsci]

Hey Oscar, thanks man! Cheers, Bill

[@thomasanderson8537]

Thanks for this very informative video. It’s something I have always wondered about too.

[@watchartsci]

I was very fortunate in talking with Marco Lang before he left Lang & Heyne, and got great responses from Kari Voutilainen, Roland Murphy (RGM) and Rexhepi Rexhep ... Fun to learn from the masters. Take care and be safe, Bill😷

[@donjuan150]

Wonderful topic....great to hear from some of the greats on why they use a slower Hz. I do enjoy seeing the balance wheel's screws and some details while beating.

[@watchartsci]

You are a true connoisseur Don! Those high beats treat their movements like a rented mule. Take care, Bill

[@almcl9391]

Great piece Bill. Appreciated

[@watchartsci]

Hey Al, thanks man! Cheers, Bill

[@everyones.shadow]

Thanks for another great video, Bill.

[@watchartsci]

Hey Jeremy, thanks man! Cheers, Bill

[@JimmieJohn]

I just like the smooth sweeping motion of the second hand on higher beat movements.

[@watchartsci]

Me too Jimmie John! Take care, Bill

[@davarhemyari7122]

Hi Bill, Enjoyed the video Bill (as usual). Creating a watch with high precision, long reserve, low wear and beautiful animation at low frequency is indeed an engineering masterpiece. That combined with aesthetic, functionality heritage and the sweat is worth every penny. Thanks again for sharing. Best regards Davar

[@watchartsci]

Exactly Davar, and that's how and why I like these watches. Craftsmanship! Cheers, Bill

[@wataki_watcheswatakiwatche3160]

Great video. I’m much clearer about this topic since you explained it so clearly with great support.

[@watchartsci]

Glad to hear it, Wataki. Take care, Bill

[@dgb6355]

Hi Bill, at last we got the answer to this question we’ve been asking for months now. So it is for longer reserve, lower tear and wear, aesthetics . Also the diameter of the balance wheel will determine the frequency, makes sense of course. One of your most instructive vids ever. Thank you for sharing. Regards.

[@watchartsci]

Thanks DG...I glad I got answers too! Cheers, Bill

[@davidwanstall]

Great video, thank you! It clearly explain why 3Hz or 2.5Hz is appealing to watchmakers. This leaves open the question of why watchmakers don't try to go lower. Apart from a few watches with giant balance wheels and frequencies around 1Hz, most watches don't run below 2.5Hz. My guess is that otherwise it would affect precision or the balance wheel would have to be too large and therefore complicate the movement design.

[@watchartsci]

Hi David, great point. I suspect that there's a point of diminishing returns as frequencies go lower, and you're right about the size of the balance wheel. The balance wheels on Kari Voutilainen look huge compared with other watches. (I would dearly love to have a Voutilainen...and the only thing preventing me is the price...). Kindest regards, Bill

[@j.burgess4459]

A while back, I believe Antoine Martin had a 1Hz watch?

[@bradpack9025]

very good content bill! one of your best, i think it is so cool that you got to meet that many TOP independents in one show. very jealous!

[@watchartsci]

Thanks Brad! If you happen to be in the New York area during October, you can attend the WatchTime Show. That was where I met and interviewed the gentlemen that I did. Kindest regards, Bill

[@kennethtape3362]

This video had me intrigued, and may I say, was extremely interesting. These are the sort of 'breakdowns' of the watch industry that we don't get enough of, 'well done'. As usual Bill, thank you very much for your tireless input and effort :)

[@watchartsci]

Hey Kenneth thanks man! Mechanical watches are proving to be an endless source of interesting tidbits...it's pure fun. Cheers, Bill

[@samadrid6321]

I hadn't thought of this. Thank you for this video. Big balance wheel, lower power requirements, high accuracy for lower frequency movements makes sense. I can see why high frequency requires more energy, but I also believe they can be just as accurate just not as historically connected.

[@watchartsci]

Hi Ryvr, I hope this video helps us all appreciate craftsmanship ... it's less tangible but evident nonetheless in the talents of the watchmakers with whom I talked. Great to hear from you. Cheers, Bill

[@thomasanonymous594]

Thank you for a highly interestng video!

[@watchartsci]

My pleasure Thomas. Take care, Bill

[@alc8479]

Finally someone who asks the questions we wanna know, I’ve also been curious if there’s a difference in quality or thickness of gears or metal in movements such as eta, sellita to omega, Rolex, to Patek, Lange.

[@watchartsci]

¡Hey Vaquero! Thanks man! Take care and be safe, Bill 😷

[@pmimagery1295]

Thanks for this Bill. I have been, recently, catching up on your older videos and it's great to hear from watch makers, themselves. I have a small collection of Russian watches, some vintage, some new. Since watching this video I've been looking up their beat rates. So far I've found that many of the older ones have a rate of 2.5 Hz. These are not expensive watches. Take care everyone.

[@watchartsci]

Lots of advantages to slower movements, PM-less wear and tear, more time between services, see the movements working and longer reserves. Take care, Bill

[@apars78]

Thanks Bill

[@watchartsci]

As always, my pleasure. Kindest regards, Bill

[@leestrada1]

Thank you, Bill! Great video! So we finally know. I find it interesting also that they all concur.

[@watchartsci]

Lee, yes, that's what surprised me too! They all concurred even though they had not been posed that question before. Cheers, bill

[@pauloshea3994]

Very interesting video Bill, great that you got the answers from “ the horses mouth “ Only thing now is I won’t be sleeping nights worried my El Primero is wearing away too fast and will be ending up in some watch breakers yard.

[@watchartsci]

Your El Primero does just fine. It's well-made from the ground up; so I wouldn't loose any sleep over it. Cheers, Bill

[@thomaskathy1]

Thomas L I enjoy most of your videos, since I started researching high horology timepieces about six months ago. Is informative, honest opinion and I have come to understand watches better than before. Regarding this particular video about the frequency of 3 Hz (21,600 vph), I once asked a Patek Philippe boutique sales consultant a couple of months ago, here in Melbourne (Australia), I was told it contribute to less wear and tear. Personally, rightly or wrongly, I prefer the 4 Hz. I also prefer self-winding timepieces. I find manual-winding troublesome as I need to wind frequently.

[@watchartsci]

Hi Thomas, there's no "right or wrong," as far as using 2.5Hz, 3Hz, or, the most common, 4Hz is concerned. It's just that the top watchmakers prefer frequencies under 4Hz. Hajime Asaoka, Roger Smith, and George Daniels all preferred 2.5Hz, and in looking at the finalists in the 2020 Grand Prix d’Horlogerie de Genève (that was just announced yesterday), Kari Voutilainen, Ferdinand Berthoud, Brivet-Naudot, Petermann Bédat, and MB&F (among others) all use 2.5Hz (18,000), and most of the others, except for the cheaper watches, use 3Hz (21,600). I'm sure that the salesman at Patek Philippe was sincere and not inaccurate about using 4Hz in the bulk of their watches (Rolex uses 4Hz and automatic movements in all of its watches). Most Parmigiani Fleurier watches use 4Hz as well (I have two-and they're wonderful watches); so it's not that there's anything wrong with 4Hz ... or automatic watches ... it's just that the top watchmakers use 2.5 or 3Hz and prefer hand wound. Take care and be safe, Bill.😷

[@younusimam-thesalamproject6340]

Having less wear and tear is so important. It increases the possibility of a watch being passed down for generations. Wish more consumer level watches would start using lower beatrates.

[@watchartsci]

Great point Younus! Like the Patek ad...just wearing it until you pass it down to the next generation. Take care, Bill

[@Jam1s]

I concur with everyone else. Very interesting video thank you very much for shading with us

[@watchartsci]

James sharing information about watches is the fun part of watch collection! Glad you enjoyed it .Take care and be safe, Bill 😷

[@ShaneLindie]

Very interesting video.

[@watchartsci]

Hey Shane! Thanks man! Take care, Bill

[@ShaneLindie]

@@watchartsci Hello Bill, I love the idea that you focus on unusual areas that are uniquely interesting.

[@alpenjon]

Thanks a lot for making the effort of getting to the root of it. It is interesting that there are diagonal perceptions of what is nice/quiet: Some argue a higher frequency second sweep (4Hz) is smoother, others percieve it as nervous or too hectic. For me, I am now happier with my 3Hz Tissot Ballade Chronometer :) I see now why one would be intetested in a hand winding movement. Subbed today! Have a great day!

[@watchartsci]

Welcome Alpenjon. That 3Hz Tissot is a sweet little watch. Check out the Tissot Heritage Petite Seconde-hand-would, 2.5 Hz. Here's one I like- www.jomashop.com/tissot-heritage-watch-t1194051603701.html?pt_source=googleads&pt_medium=cpc&pt_campaign=(ROI)+Shopping+-+Sale+Watches+$500+-+1000&gclid=CjwKCAjwrvv3BRAJEiwAhwOdM_1QerkMpDD5TuIMTWyqTnWBLyTOJC-ka2Gt8d12HqbQBAan9LUtjBoC7BQQAvD_BwE I'd get a nice black gator band for it, and it'd look like a million bucks! Take care, Bill 😷

[@alpenjon]

@@watchartsci That's also a nice one! I will consider it in the future, thank you!

[@huratan]

Good video Bill!

[@watchartsci]

Hey Tanzeel, thanks man! Cheers, Bill

[@kkolsen2001]

Very interesting discussion. As an engineer, I appreciate the discussion of the various trade offs involved in these movements. Thanks for putting this excellent video together!

[@watchartsci]

My pleasure Kurt! What kind of engineering do you do? Cheers, Bill

[@kkolsen2001]

@@watchartsci I'm a chemical engineer doing consulting in the renewable fuels industry (among others). Fascinating stuff!

[@watchartsci]

Sounds interesting! Mechanical watches are based on renewable energy...winding and walking. Kindest regards, Bill

[@kkolsen2001]

Agreed Bill - that's partly why I find mechanical watches so intriguing!@@watchartsci

[@johndoe-ln4oi]

Wonderful, wonderful video, Bill! This is one of the best, most informative watch videos I have seen. Thank you for your time on this. I do have one question; when you mention "increased inertia" of the lower beat movements, is this exhibited in the longer power reserve, increased accuracy mentioned by some of the manufacturers or both?

[@watchartsci]

Hi John, thanks man! Basically the higher moment of inertia (a bigger, heavier balance wheel for all practical purposes in a watch) means that the oscillation frequency is less susceptible to alteration by external influences and so more accurate. Take a look at the size of the balance wheels in Kari Voutilainen's watches in this profile: www.watchtime.com/featured/kari-on-meet-watchmaking-star-kari-voutilainen-profile/ However, I could write a book on what I DON'T KNOW about the moment of inertia. That's why I depended on the really top watchmakers to provide the clues of where to look for wristwatch excellence. Cheers, Bill

[@johndoe-ln4oi]

@@watchartsci Thanks, Bill! I am still fairly new to this and still learning.

[@juniorjohnson5961]

Hi Bill It's cold & raining with snow mixed in 🥶. didn't leave the house today , catching up on your old videos 👍

[@watchartsci]

A great thing for a dreary day, Junior. The interview with Marco Lang was at the WatchTime Show in New York ... the only one he ever attended. Take care, Bill

[@bengchiatseah3908]

for my chronograph watch, i understand why the movement is 2.5hz. the second hand markers are divided by 5 n the watch can time accurately to 1/5 (0.2) of a second. thanks for all your very informative videos.

[@watchartsci]

Hello Beng Chiat Seah. The lower frequency also allows for a larger balance wheel with more inertia for keeping a constant beat. Kindest regards, Bill

[@stevenjohnsrud4655]

One of your best Bill.

[@watchartsci]

Thanks Steven! I enjoyed making it. Kindest regards, Bill

[@southnc63]

Another nice video, Bill. I agree for the most part with what you state. However, my higher (4) Hz watches do tend to be more accurate than those that are 3 Hz or less, and I think a chronograph should have at least 4Hz for granularity in measuring time.

[@watchartsci]

Hey, SouthNC63 ... we've been led to believe that 'higher is better,' but if that's true, you can run down and get a $10 quartz that will be more accurate than a Dufour Simplicity ... Probably the majority of my watches are 4Hz...especially the entry level ones. I think that of my 4Hz watches, my Habring2 Felix is the most accurate. For 3Hz, my Patek Philippe Calatrava...but then there's my 2.5Hz H. Moser that's both accurate and has a nice long charge. Check out Roger Smith's talk in New York City, the section on 'Fast Beat.' at kzbin.info/www/bejne/pKOcgXd8drWdbsU about 19:20 . That addresses why the best watchmakers use 18,000 vph, Cheers, Bill

[@lefataliste]

Very interesting video. I think the musical side of the problem should be added: lower beat rates are simply more musical because you can distinctly hear the ticking, whereas the higher the beat rate is, the less distinct is each beat of the ticking. For me, as a user and wearer, not as a watchmaker, it’s this musical side of things added to the esthetic one (larger more visible balance wheel) which is the most important. Best.

[@watchartsci]

Great musical note you've added to watch-ticking Emmanuel! Thank you! Take care, Bill

[@kojiattwood]

Excellent point, sir!

[@SylvainDuford]

Very informative video. Kind of dispels the notion that high-beats are better and more accurate.

[@watchartsci]

Hi Sylvain. I had noticed that most of the top watches were at a frequency under 4Hz but I didn't know why. It turned out that all of the watchmakers I talked with used a frequency of only 2.5Hz. Love mysteries in watchmaking! Cheers, bill

[@andresfg6788]

This made appreciate more the 18,000 vph on the 321 Speedmaster. The movement is really what takes it apart from regular production Speedmasters

[@watchartsci]

I did not know that the 321 Speedy was 2.5 Hz. That's great! Take care, Bill

[@billcosgrave6232]

Good video!

[@watchartsci]

Hey Bill, sorry you had to wait! Thanks man... Cheers, Bill

[@amintaslneto]

A fascinating subject indeed Bill. Thanks for bring that up and for sharing these nice interviews. Boy, I had a simular communication challenge with Rexhep Rexhepi once in a watch event. The good news was that the universal 'watchmaking language' made it happen ;) Nevertheless, I hope you've found Akrivia timepieces as impressive as I found mainly around tourbillions. Now to the beat rate topic, I guess you were spot on about that 2.5hz-3hz rationale. Besides, power consumption optimization this is definitively the best rate for movement viewing and listening! Now if one likes enjoys watch motions from an outside perspective nothing is cooler than seeing a watch hand 'flying' at 36,000bph :) Best, Amintas

[@watchartsci]

Whoaaa...flying at 5Hz!!! I may go blind. I think that Rexhep wanted to help as much as possible, but it wasn't until his assistants got through to him what I was asking about that he could reply. There is no doubt that the Akrivia watches are impressive. Cheers, Bill

[@amintaslneto]

@@watchartsci Indeed my friend. Rexhep represents the new watchmaking generation which is pretty exciting. Hope he reaches Journe level within a few decades. Best, Amintas

[@romanjeremy5156]

@@watchartsci Hi Bill I'm curious what your opinion is on the Zenith Defy 21: 5Hz for time keeping and 50Hz ! for chrono. Very fast, but still a reliable movement I guess...

[@billcosgrave6232]

I will have to do some research myself but I suspect you are correct. A higher beat movement may require more complex gearing and consequently be less visually appealing. A slower beat movement may provide the watchmaker with more design options while still allowing for a certain level of precision.

[@watchartsci]

We keep forgetting Bill: a $10 quartz will beat anything mechanical for accuracy in time-keeping. I don't think complex gearing is the issue so much as beauty in simplicity. Much more difficult to create a simpler watch with optimized timekeeping than a gear-heavy contraption. The same is true in programming; a simple, elegant algorithm and structure is harder to conceive and build than piling code on a problem to solve it. It's what I liked about design patterns and lambda calculus applied to programming. Initially more difficult to grasp and appreciate, but ultimately it leads to better programs. Cheers, Bill

[@canonyeo4286]

Bill, l so happened to watch this video today. Here's my take from a builder's perspective. In buildings, there're two important aspects, architecture and engineering. In terms, of engineering, perhaps, we can likened them to high performance cars. Take for example, the GS caliber 9SA5, which runs at a high frequency, maintaining 80 hours of power reserve, regulated at 6 positions to keep precision over a long period of used. It does not look as nice aesthetically as the watches presented, which, focus on architecture, but, it does look reasonably nice. Then, we can look at the 9R02, handmade in the micro artist studio, in very limited numbers. This is not only a high performance watch, but, with beautiful architecture too. Its finishing is second to none. But, of course, they do have Phillipe Dufour to thank. In the credor line, they do have calibers that focus just on architecture, or, low performance watches, complications aside. We cannot really separate the two, as they depend on each other. This is my command sense views. The experts views are much appreciated. Thanks for this very interesting topic.

[@watchartsci]

Canon, you can pick up a used Ferrari for very little money because, while high performance, they eat themselves up. If you want to make a car comparison, check out a Singer ... both their cars and watches. Take care and be safe, Bill😷

[@officialMainspring]

I love 18000 vph movements. something about the look of the "chugging" beat rate that is so pleasing to the eye... and with modern manufacturing and adjustment techniques, don't have to worry about accuracy as much. if you gave me a choice of 2 of the same watch that feature manual wind movement with one slow beat and one hi beat with display backs, I'd go for the slow beat version every single time.

[@watchartsci]

Same here Mainspring ... slow and fun to see the beating heart of a watch. Take care Bill

[@oftheessencetimeis1892]

I love this type of informative video. Are you planning to do this type of activity again when they bring back the watch shows?

[@watchartsci]

Yes I will, Essence! Just yesterday I learned that this October, the WatchTime Show in New York is back this year! Take care, Bill

[@oftheessencetimeis1892]

@@watchartsci excellent! Thanks for the info. I hope to see you there. I’m just on the other side of New York from you

[@marguitvaldez4792]

I am surprised only Mr. Murphy touched up in the wear and tear issue. The lower the frequency means you will have less internal motion, and more important, less stress in the parts which is more durability. Regardless of the advances made in materials, reduced friction, etc. a spring or counterbalance moving at half of frequency statistically has better chances to have a longer life.

[@watchartsci]

All of the interviews, Marguit, were off-the-cuff and in the middle of a noisy watch event ... but you are correct. Lower frequency; life. Take care, Bill

[@toegunn4905]

It's always interesting to compare the approach of the independent watchmakers to the mass market luxury brands. It seems most luxury brands are moving closer and closer to movements for the sake of numbers, with some decorative flourishing for some flair. The independent have to focus on the composition of the piece as a whole, granted most don't have the resources to get into the strange new materials and tech that seems to be popping up every year. Limitation forces the artist to innovate in much more relatable ways. A company like Richard Mille is just making gaudy excess because they can.

[@watchartsci]

Hi Toegunn, I spent some time with Rolf Lang in Dresden, and to me the biggest problem that Independents have is their own creativity. Often it bumps into business realities ... that's why I like to support the independents. I still have no idea why a watch with a not-brand-manufactured movement and Mille's designs is so popular and expensive ... but that's just one more mystery in watch collection that I cannot fathom. Take care, Bill

[@digggert]

I'll just leave this note before I start watching to see how much of it I got right in the end :) - lower frequency =more prone to outside disturbances -higher frequency =more stable and therefore accurate, however they consume more energy. - large balances with screws look. traditional and nice and so low frequency watches are very appealing. -theoretical max time to overhaul should be significantly longer for low freq. escapements

[@watchartsci]

Hey Diggert, here's what we're all faced with 1) Physics and 2) A practice that seems to counter a common understanding of that physics as applied to watchmaking. The empirical reality is this: the top watchmakers in the world... and this includes Philippe Dufour and Roger Smith in addition to the gentlemen I interviewed...prefer a lower frequency in their watchmaking. So the issue is not what we know, but what we must learn from these top watchmakers. Cheers, Bill

[@bjejoh]

Can you comment on the Breguet 7727 10Hz. Why did they make it? Would you have it in your collection?

[@watchartsci]

Hey John, the Breguet 7727 is a brilliant design with the balance post suspended between magnets. A friend of mine has one, and they keep excellent time. Cheers, Bill

[@Champsterz]

probably down to trade off between accuracy and longevity? A chronograph watch probably tend to have higher frequency as a stop watch. The normal time only don't need to be that precise.

[@watchartsci]

I don't think that's it Richard-the trade-off. It takes a lot finder tuning to have an accurate 18,000 so/hr than a 28,800 so/hr. That's why I value the lower frequencies (belong 28,800). Take care, Bill

[@fliegerb777]

Nice video, Bill. Coincidently I'm in the market for classic pilot watch and right now I'm deciding between these two IWC watches with in-house movement where one has 2.5Hz and the other has 4Hz. Your video really opened up my horizon. Thanks, Bill. Cheers.

[@georgejpg]

Might be a stupid question but how could a watch have a decimal frequency without missing individual seconds and being imprecise for timing short things

[@watchartsci]

Hi Jimmy, what are the two IWC watches you're considering? Cheers, Bill

[@watchartsci]

Jimmy, here's a link to a German site where they make some very interesting pilot watches using the Unitas/ETA 6498.1 (2.5Hz) You might like the prices too. www.tourbywatches.com/collection/pilot-anniversary-45/ Cheers, Bill

[@fliegerb777]

WatchArtSci Hi Bill, either the IW325401 Vintage or the IW387806 Exupery.

[@fliegerb777]

WatchArtSci Hi Bill, thanks for the link, Tourby is very good. Unfortunately now I'm looking for the IWC with in-house movement. I have the Stowa 90th Anniversary with 6498 movement. Cheers.

[@DoctorAB282]

Thanks Professor you should be the of US watch making regulatory agency

[@watchartsci]

Hey Doc, does the US even have a watchmaking reg. agency? Glad you liked it. Kindest regards, Bill

[@DoctorAB282]

😊😅😂😂😂😂 I mean the head of US watch making regulatory agency write a proposals ✌️

[@bobrouleau7410]

Great video Bill! Now it raises the question of why does Rolex use 4 Hz movements? For that matter is a 4 Hz movement more accurate than 3 or 2.5? From your video it seems as if the larger balance wheel wins back some accuracy from the slower beat rate and clearly improves power reserve. Are there COSC chronometers with low beat rates I wonder?

[@watchartsci]

Hi Bob, thanks! Rolex makes about 1.4 million watches a year, and 4 Hz movements are more forgiving than those with lower frequencies. So, if something is off, there's less visibility because with each semi-oscillation at higher frequency, the time of the flaw can be lessened or as Roger Smith suggests, 'hidden.' F.P. Journe could care less about COSC and a Poinçon de Genève. His chronometers meet and exceed both COSC chronometer specs, and he (unlike Patek Philippe) have not given themselves a Poinçon de Genève in the form of overlapping 'Ps.' Cheers, Bill

[@josevasquez1781]

Okay then, I get the idea small balance at higher frequency oscillation, large balance lower frequency oscillation which then looks great on hand wound nicely finished movements. For years I understood the wear and tear of 36K and above HZ movements but also knew to be more accuracy because of the fast oscillation of the balance. I don't really get why many watch manufactures of the lower VHP movements still recommend 4-6 years service intervals.

[@watchartsci]

I don't know either, Jose. They may think that the same must be true for all watches regardless of the frequency. Take care and be safe, Bill😷

[@josevasquez1781]

@@watchartsci you working hard and doing excellent work for us here on YT, thanks Bill.

[@GeorgeWadsworth]

You should look at R W Smith lectures, unique perspective.

[@watchartsci]

His watches certainly fit into this group, George. Take care, Bill

[@j.burgess4459]

My Blancpain Barakuda runs at 3Hz. I have a vintage Omega military watch that runs at (I'm pretty sure) 2Hz. Interestingly my latest toy (a Patek 5296G-001) runs at 4Hz. The earlier iteration of the calibre used to run at 3Hz, but they increased it. I think I heard somewhere that it takes a little longer to regulate a calibre at lower frequency?

[@watchartsci]

Hi Jay, did you check the frequency on the Omega Military with a timegrapher? Having a 2Hz watch would be very cool, but they tend to be 2.5Hz. Upping from 3Hz to 4Hz is a common practice because they tend to be simpler all around and require more frequent service ($$) and wear out quicker. It most likely does take longer to regulate lower frequencies, but it's required less often as well. Take care and stay safe, Bill 😷

[@j.burgess4459]

​@@watchartsci I didn't check it, it could be 2.5Hz - it's a 1953 "Fat Arrow"6B/542 made for the Royal Air Force. I also have a 1943 Jaeger-LeCoultre (a special order for the RAF during WW2) which is currently at JLC for vintage service appraisal - that one really could be as low as 2Hz, I think. (EDIT: I did some online research; an Omega calibre 283 would indeed be 2.5Hz. Sometimes the military order watches were regulated to a higher level, but I guess it's unlikely they would have slowed them down.)

[@watchartsci]

@@j.burgess4459 It sounds like you've got you mitts on a very cool timepiece! Take care and stay safe, Bill 😷

[@j.burgess4459]

@@watchartsci Yeah, militarily watches are a whole field. Back in the 40s and 50s the watches issued to aircrew (especially air-navigators) were a very big deal - navigators needed the most accurate chronometers available, which could also resist the vibration and magnetism in aircraft cockpits. The 6B/542 would have been (I think) for pilots and air-controllers. The JLC I have is a 6B/159 which was for navigators.

[@richarda9961]

The more accurately a watch is constructed The Lure of the beat rate it can run and still keep excellent time

[@watchartsci]

Hi Richard, that sounds right to me too. Cheers, Bill

[@amundbjerve]

It makes sense that increazing the size of the balance wheel will increase the accuracy. Remember the pendulum clocks with their slow beat. The clock in Big Ben is accurate to less than a second in 24 hours.

[@watchartsci]

Hi Amund, great example! So Big Ben loses a second a day...needs to go to the shop! Cheers, Bill

[@digggert]

This comparison does not work really. A higher mass, therefore higher rotational moment if inertia and therefore lower frequency balance wheel will be more prone to disturbances by accelerations imposed upon it. With a precision pendulum clock, outside influences are ruled out due to their location. Think of it this way: if you wiggled around a pendulum clock, would it keep precise time as a high frequency tuning fork watch or quartz would?

[@digggert]

I think you'll find an answer to why large pendulums are accurate in the term quality factor (check it out on wiki) which puts the energy stored in the pendulum in relation to the frictional losses. That number is - with a high mass pendulum - obviously very high and so the impulse required to keep it going is very low compared to the kinetic energy of the pendulum. However, the influence of outside accelerations is what ruins the comparability of pendulum clocks and wristwatches.

[@digggert]

Having now thought about and researched a bit: The quality factor is indeed what we are looking for and someone explains it here for watches in a very good way en.m.wikipedia.org/wiki/Talk:Balance_wheel My mistake was: the increase of balance mass indeed improves the quality factor, but thr resulting decrease in frequency counteracts that improvement.

[@watchartsci]

Diggert, we need to listen to the watchmakers who actually make and design watches. Otherwise, we speculate. Thanks for the link on the balance wheel. Now check this out and respond (please!) Start about 19:20 where Roger Smith talks about 'Fast Speed' kzbin.info/www/bejne/pKOcgXd8drWdbsU about 19:20 Thanks, Bill

[@varunu4176]

Here's my take...independent watchmakers can't afford tech the giant companies like the Swatch, LVMH and Richemont can and hence achieving a longer power reserve is a challenge. Accuracy with lower frequency can be achieved by a larger balance wheel and larger balance wheel is also easy to handwork compared to a smaller one. The larger balance wheel is also easy on the eyes to look at the beauty of the balance ticking.

[@watchartsci]

The only problem with that analysis, Varun, is that so many of the big companies prefer to use off-the-shelf movements by ETA and Sellita. If they have the motivation (willing to make the investment) in movement development; they would. When Richemont invested in a movement, they did so by developing a system to replicate movements through ValFleurier, and so Piaget, Cartier and even Vacheron Constantin, all now share a movement initially developed by Cartier. If you look at the work of Roger Smith, you see all hand-made elements. With F.P. Journe, you see the same thing but on a slightly larger scale. You can have anything made that you don't have or are difficult to make, such as pinions and gears; but they're not that difficult. Take care, Bill

[@gauranggppatkar2968]

I am no expert in this but I think another reason why its lower than 3 hz is (based on my knowledge of Tissot powermatic 80) that the hairsprings they use are non-magnetic as in Tissot they use silicon hairspring, with this I think its not possible to achieve high beat rates. I think its for more power and resistance to magnetic fields and temperatures they compromise on beat rates. That is totally an assumption from my side but I would love if you could confirm that with an expert.

[@watchartsci]

Gaurange ... interesting hunch, but magnetism has nothing to do with the frequency selected by the watchmaker. Lower frequencies are used by the top watchmakers, all using non-magnetic hairsprings. Lower frequency provides longer movement charge and longer times between service. The higher frequencies (4Hz and above) are chasing accuracies while wearing out the parts faster and reducing the charge time. Take care and be safe, Bill😷

[@gauranggppatkar2968]

@WatchArtSci Really nice to know that. Earlier I used to think that all highend watches used silicon or non-metalic hair springs which limited their beat rates. Interestingly thats not the case. Thank you & take care too 🙂.

[@shipmate3577]

So they want longer power reserve, but at the cost of accuracy.

[@watchartsci]

Hey Shipmate...You can optimize your accuracy with a $10 quartz watch. Working with mechanical watches, you either have craftsmanship and creativity ... or something less. You don't seem to be the kind of guy who accepts 'something less.' Cheers, Bill

[@DrEvil814]

What Hurts?

[@watchartsci]

Dumb comments ... ouch!

[@christianfrech6993]

💙

[@watchartsci]

👍

[@ForbinColossus]

Some people you interviewed seemed to be defensive (!) in their answers rather than entertain a more objective theory of why watchmakers prefer lower hertz rates .. A few, like Roland Murphy, pointed out larger balance for visual appeal and improved reliability is hinted at. The young Montblanc rep seemed full of it - dished out the corporate line that makes a watch fan's eyes glaze over...

[@watchartsci]

Hi FC, I don't think they were usually asked questions like that, and the young man from Montblanc, was pretty good I thought. Were someone to ask me about the corporate relationship with Minerva and then switch to a question about low frequency rates, I might be off my game a bit too. I especially liked Marco Lang's and Kari Voutilainen's replies, but I was happy to get the wisdom of all of the watchmakers that I did-especially since all but one had actually designed and created an actual movement. Take care, Bill

[@patbackus7668]

Don’t know about you but I don’t need a weeks power reserve ! I love giving my watch life every other day

[@watchartsci]

Hey Pat, I only have 1 watch with a week's power reserve. Cheers, Bill

[@neilpiper9889]

I have 2watches running at 18000bph, a Kirovskie watch made in 1939 at the 1st Moscow watch factory, and a Omega 266 handwound from 1954. My Vostok watches run at 19,800 Bph which is unusual and exclusive to Soviet watches I think. I have a Soviet Volna Precision from the 1950s with an aftermarket see through caseback and that runs at 19,800 Bph too. Perhaps that's a good compromise speed. Most of my more modern watches run at 21600bph. I have one that runs at 28800bph. A Seagull Ocean Star Diver watch. Its painful to listen to it when you put it to your ear it's so manic. Luckily it has a solid caseback so you can't see it's frantic balance wheel.

[@watchartsci]

Hey Neil, that's very interesting about the Kirovskie from '39. I use Seagull ST36's a lot in my DIY watches-nice big movements for me to work on and not as expensive to break as the ETA/Unitas 6497/8's that they replace. They run as smooth as silk at either 18,000 or 21,600, and I've been able to tickle the regulator to near 0 error. Pas Mal... Cheers, Bill

[@jamliaqurratiaini5042]

balance wheel secret, proper speed + proper torque = efficiency, consistency and accuracy. most watchmaker are artist they doesnt articulate technical term the way engineer or commoner does.

[@watchartsci]

Jamlia, most watchmakers are watchmakers, not artists ... some are both. Marco Lang is a watchmaker and masterful designer. I would like to hear your opinion of silicon hairsprings. Take care, Bill

[@jamliaqurratiaini5042]

@@watchartsci @WatchArtSci silicon hairspring has it's own benefit, where it's resistant to wheater and magnetic interference. steel and alloy has been used longer, with already predicted deterioration rate, this help with various off the shelf component selection which helps to create more consistent watch because you doesnt need to retrofitted the watch movement design to the component (its like tearing down the whole house just because you wanna get the couch out off the basement), component to movement design that what important. and yes people seen silicon as convenience but steel and some alloy hairspring as sustainability. but the whole watch industries has tried to distract our attention(I believe), from what most important the most. its linear power regulation of the mainspring the most important(to achieve constant power), because mainspring does not as accurate as the regulator wheel and its spring. as you already figured that most the exceptional watches stays 18.000vph, proofing there is somewhere else need to be touched for extra attention, of course not forgetting the balance wheel assembly. linear constant power regulator for the mainspring to regulate amount the unwound hairspring during 100%-0 of reserved energy probably the next thing need to be developed in this modern era of mechanical watches. take care and godbless

[@watchartsci]

@@jamliaqurratiaini5042 All of my comments have to do with collecting mechanical watches with transitional metals; not metalloids like silicon. In a word, silicon is a better material than transitional (and traditional) metals used in mechanical watches insofar as they are non-magnetic, keep their shape and precision. That's not the point. It would be like using acrylic paints on a Van Gogh. You cannot adjust a silicon hairspring using a curb regulator with a beautiful swan neck adjuster. As for using the lower frequency by top watchmakers ... it's a matter of artistry, and I bet you appreciate that as much as anyone who love horology. Take care, Bill

[@jamliaqurratiaini5042]

@@watchartsci 100%

[@MrSigmaripon]

A lot of cheap Seikos are 3hz. These have a reputation of running for ever with reasonable accuracy.

[@watchartsci]

Hi Mr S! Yes, there's the irony! I've taken up watchmaking (in the most pretentious sense...I assemble parts into a watch), and my favorite is the ETA 6497/8 or [even better--the Chinese Seagull clones ST 3600/3620] The -1s run at 18,000 and the newer -2s at 21,600. Naturally, I prefer (now) the -1s. None of these movements I've come to love are anywhere near the specs of the watchmakers seen in the video...nor produced by craftsmen. That's ok with me, and while I save up for the Lang & Heyne with the trigonal bridge, I'll knock out my own watches secure in the knowledge they my creations and those of the greats share one thing in common: the frequency. Cheers! Bill

[@ForbinColossus]

Bill, see this article on New York City's clock man: www.nytimes.com/2018/11/02/nyregion/the-man-who-turns-back-new-york-citys-clocks-hand-by-hand.html

[@watchartsci]

Thank you very much! Now I have to subscribe to the NYT! Cheers, Bill

[@kbrackins]

Just looked it up, he starts explaining it with his subtopics Fast Beat at about 19:20

[@watchartsci]

Holy smoke! He didn't mince any words ..."a faster beat hides inefficiency in design"... Kevin, I cannot thank you enough! That section of Fast Beat needs to go down as "an iron law of exceptional horology!" Kindest regards, Bill

[@kbrackins]

WatchArtSci Thanks Bill, luckily I had viewed one of your previous videos a couple of days ago asking this same question. I watched this Roger Smith NY Horological video two days ago and when I saw your question resurface, I thought this might provide the answer you were looking for.

[@watchartsci]

Ironically, that little clip put it more succinctly and accurately than I could, and it summarizes everything I was told in the interviews! What a gem! Kindest regards, Bill

[@kbrackins]

WatchArtSci suggestion: Bill, please update your About section on your KZbin channel so I can follow your other social media. Also, your URL on the about page isn't working either. Thanks, Kevin

[@watchartsci]

Ok Kevin, yes, I'm behind on site maintenance...mea culpa. I'll add it to my to-do list. Kindest regards, Bill