More BPH usually means more expensive lubrication needed, more sensitive to wear/ expensive defects. No stories like "my dad's Seiko5 keeps on going for 40 years without maintenance"

 

You forgot the Seiko 5740C movement, their first 36,000 bph movement. It was made in 1967 to show the durability and precision of Seiko, with only Girard-Perrigeux beating them to the market as watch companies raced to be 'the first'. The Lord Marvel 36000 was made in a limited run of only 36,000 pieces in 1967 (my avatar watch being one of those rare '67's). The line was then continued though what I believe was 1973 with those later year models being somewhat relatively abundant.

A 28,800 bph Swiss Movement runs at 8 ticks per second, or 4 Hz. The higher beat count 0f 36,000 is 10 bps or 5 Hz. This is really designed to overcome the fact that the human wrist has a movement in daily life around 2-3 Hz, the idea being to get away from that should help 'on the wrist'. I would think too the extra precision would theoretically help just sitting motionless as well.

Anyway, ultimately just relying on a higher beat count won't get you more accuracy. As you stated, the ubiquitous ETA 2824 and its variants that tick at 28,800 bph are all very accurate watches, easily adjusted to -4/+6 seconds per day COSC standards, though rarely registered as such. Rolex Cal 3135 at its siblings are known to be regulated to under a second a day with relative ease ticking at 28,800 bph.

Grand Seikos at 36,000 bph are regulated to the GS standard -3/+5 spd which is tighter than COSC. Now just how much of that is due to the higher beat count and how much is just the great precision that Seiko exacts on every part is open to debate.

Zenith chronographs with the 36000 bph count were designed to allow ticking off the sub-seconds counter is perfect 0.1 second increments, and early Rolex Daytonas used that movement but no longer. Zenith still manufactures the 36000 bph chronos and they are great movements.

I can tell you the 36000 bph second hand sweep is noticeably smoother than a 28,800 bph sweep. That is what I find so appealing.

 

Higher beat rate is just the easy way to better accuracy

Patek Philippe has been producing chronometer grade movements for over a century and they all have an 18,000bph or 19,400bph beat rate.

It takes more skill to produce a slow beat chronometer but it will hold the accuracy and precision much longer than a high beat movement along with the resulting lower wear rate.

 

Does bph really matter in a spring drive Cal 55r66? Since it is a cross over of Mechanical and Quartz oscillator for accuracy and precision?

 

The accuracy of a spring drive is dependent on the quartz oscillator which runs at many times the frequency of a mechanical watch. The mechanical part of the spring drive is there to provide electrical power to the quartz control circuit and keep the hands moving .. without the quartz control it would simply run fast.

 

Right so in this case it does not matter since Accuracy and Precision is dependent on the Quartz and the well made mechanical part............

I want a Spring drive one day

 

The higher the beat rate, the less the effect a perturbation will have on time keeping. Chronometer-grade low-beat escapements probably use a more massive balance wheel to ward off perturbations.

By the way, are you in Cambridge, England or Cambridge, Massachusetts?

Best wishes,
Myles

 

Interesting and informative responses gentlemen. Thank you for contributing.

Hello neighbor Myles, I do live in The Republic of Cambridge, MA

 

I also remember the Bulova Accutron which generated its bph by a tuning fork powered by a battery. No knowing much about movements I am wondering if the design of the Accutron (tuning fork) might have influenced Seiko's Spring Drive and other hi-beat movements?

Here is some info on the Accutron:

"The most significant Accutron calibers oscillate at a rate of 360Hz, equivalent to a mechanical rate of 2.592Mbph. For comparison, quality 'hi beat' mechanical watch movements operate at a rate of 36kbph. Because of the tuning fork's extremely stable oscillations, an Accutron may be regulated to within +/-2 seconds per day or less, double the accuracy of a modern Top- or Chronograph-grade ETA mechanical movement. The tuning fork's 360Hz vibrations also give an Accutron its characteristic humming sound and smooth sweep second motion. The distinctive Accutron sweep second has only recently been replicated in modern movement designs, such as the quartz-based Seiko Spring Drive and Bulova Precisionist. ( http://www.decadecounter.com/accutron/history.htm )

 

I also remember the Bulova Accutron which generated its bph by a tuning fork powered by a battery. No knowing much about movements I am wondering if the design of the Accutron (tuning fork) might have influenced Seiko's Spring Drive and other hi-beat movements?

Here is some info on the Accutron:

"The most significant Accutron calibers oscillate at a rate of 360Hz, equivalent to a mechanical rate of 2.592Mbph. For comparison, quality 'hi beat' mechanical watch movements operate at a rate of 36kbph. Because of the tuning fork's extremely stable oscillations, an Accutron may be regulated to within +/-2 seconds per day or less, double the accuracy of a modern Top- or Chronograph-grade ETA mechanical movement. The tuning fork's 360Hz vibrations also give an Accutron its characteristic humming sound and smooth sweep second motion. The distinctive Accutron sweep second has only recently been replicated in modern movement designs, such as the quartz-based Seiko Spring Drive and Bulova Precisionist. ( http://www.decadecounter.com/accutron/history.htm )

I had a Bulova Precisionist. It uses twin quartz like many others, then uses a 16-step per second stepping motor to closely resemble a continuous sweep. It is not truly smooth, take a close look, use a loupe if you have to. Seiko Spring Drive is truly smooth and continuous.

 

I understand the accuracy of the Precisionist is very good about plus/minus 10 seconds a year! I also see them selling for between $270 - $390.