32 metronomes attaining spontaneous synchrony

This Japanese video shows 32 metronomes set rocking on a wobbly surface. They begin in a state of chaos, and as they feed motion into the table, they begin to influence one another, until, 4 minutes later, they attain synchrony. It's quite remarkable (and a little sad for those of us with a nonconformist bent!).

メトロノーム同期 (32個) (Thanks, Fipi Lele!)


    1. I was wondering what would happen if one was a little off. My guess is that the strong motion of the table would be enough to force it to stay in time. After all, even if they were all perfectly set to the same beat, each one had to move out of beat in order to synch up like that.

      Presumably anything set to 1/2 speed, or a 1/4 or 2x or whatever, would manage to keep its own speed (although it would still synch up with the rest, just at 1/2 speed).

      1. The cool part is, if just one of them was set to a non-harmonic frequency, it might inject enough chaos into the system to prevent the others from synchronizing.  But chaos is funny – a slightly different frequency could have the opposite effect.

          1. Nope, chaotic systems are not predictable, by definition.

            Chaotic systems may be deterministic, but this is not the same thing. With a deterministic chaotic system you can always work out what will happen at the very next time point, but you cannot predict what will happen at the hundredth time point, without working out all the time points in between.

            It’s a subtle, but important, distinction.

    1. You’re more right than you know.

      The original purpose of marching was to get ground troops from one place to another efficiently in a coherent group, however it was discovered by military commanders that marching has an additional benefit in that it is: “thought stopping” (where individual soldiers are too busy focusing on maintaining correct time that there is literally no time to think: “why am I here?” “why am I fighting?” “is my enemy really my enemy” or “I want to go home to my family”) which preempt thoughts of sedition or desertion. 

      There is a direct correlation between the amount of “thought stopping” and the complexity and difficulty of an army’s drill; q.v. “goose stepping” of the historical armies of the German Third Reich or the modern armed forces of North Korea:


  1. Anyone who can tell if they gave some impulse to the wobbly surface (outside camera lens angle)? Really would like to try that in my local music store. Hey, it’s not “Stairways”!

    …but then, this reminds me of Hammerzeit… >.<

    1. No, the synchronous behavior at the end is sustained for nearly a full two minutes before the camera shuts off. Cory says “four minutes” above but they are actually nearly all in synch much earlier than that, with just one metronome 180º out of cycle for a time.

      If it was just an example of beats they would be out of synch again almost instantly.

    2.  Nope. Physics problem solved by Christiaan Huygens while lying in bed with the flu and having nothing to do all day but watch two pendulum clocks on a shelf.

  2. Actually, it’s not all that surprising – the table isn’t fixed, rigid, and influences the motion of each metronome once it starts moving itself. Seems to me it’s only a matter of time before there is statistically more density of periodic motion at one point in time, which slowly begins to set the surface in motion, and eventually each metronome falls in line with the motion of the table. In this sense, it’s not really the metronomes influencing each other so much as it is the table dictating the movements of the metronomes.

    I agree it is a bit depressing, though…

    1. You had me thinking about divine intervention more than subconscious conformity, but then I realized the table is subconsciously conforming as well.

    1. yes!

      Everything adds to the balance. Extremes will sway like a pendulum… or a metronome I suppose!

      If I could only apply this to my washing machine, I wouldn’t have to go rearrange the clothes every time I do laundry. 

    2.  i too thought of intelligent designs fictitious claim that order cannot arise out of disorder.
      its a rather nice model for evolution actually, those which become synced become more fit, as the synchronized ones exert more influence on the table, thus those which swing against this influence lose energy while those who swing with it or slightly behind it gain energy, then just following the simple laws of physics from a random set of swinging pendulums you get an ordered set of pendulums all swinging in unison. they arent trying to, they arent saying “hey swing my way” its just as two happen to get in sync they influence the selective pressure of those around them to also get in sync.

  3. “a little sad for those of us with a nonconformist bent!” — Look at it this way, CD: many may work to a common beat, but the harmony of each is unique. Think of the difference between what Chopin would make of that rhythm, and Stravinsky. 

  4. The trick, for us nonconformists, is to recognize the motion of the table, and avoid its synchronistic, gravitational pull.

    There is no spoon.

  5. The only thing I don’t like about it is it reminds me of the experiment where two asynchonous heart cells, placed adjacent to each other, become synchronous.  And I thought it was cause the heart was special, but this just makes it seem like a clockwork trick. 

  6. There’s an excellent book called Sync by Steven Strogatz that explains the phenomenon. Like fractals, sync arrives as a consequence of feedback. Interesting stuff, I had two homemade synthesizers that would sync if you left them running on arbitrary settings, as they were feedback based. 

  7. I was rooting for the little non-conformist (right column, second up from the bottom). He’d managed to confound the crowd by synchronizing with them in opposite phase. But then, sadly, at 2:37 even he falls in line with the crowd.

    Truly, a sign of the times.


        1. see how the guy in front of him assisted in his conversion by swinging out of sync for a beat or two.  cursed imposter non-conformists!

    1. Third one back in the left blue row never perfectly syncs up.. he’s a fraction of a beat behind everyone else. 

      I’ll call it the chubby kid in gym class effect.. he wants to be part of the crowd, but just can’t keep up. 

  8. So the moral is: if you’re on solid ground, you can be a non-conformist, you can be an independent thinker/actor/agent..  On shaky ground, eventually, everyone thinks the same.

  9. tangentially relevant, but this is the theory behind resonance in mechanical watches/clocks (Breguet, FP Journe, Antide Janvier), those which utilise two oscillators set to the same frequency, which is supposed to aid — not precision, but rate stability.

  10. I crossed my eyes slightly while looking at this and then refocused. It was weirder at the beginning than at the end. and a little 3d!

  11. …and in other news: 

    “4 minutes later, they attain synchrony. It’s quite remarkable (and a little sad for those of us with a nonconformist bent!)”

    Cory has never been in a band …and probably sucks at dancing.

    1. I’m a drummer with a strong love for rhythm, and this video still filled me with crawling horror.

      It was like being on Camazotz, and I wanna get the hell outta there.

  12. Wow.  I was thinking that these must be sophisticated metronomes that have some sort of cellular automata coding to allow them speed up or slow down according to what their neighbor was doing.  And the actual solution was the lowest of low tech: placing them all on a slightly wobbly surface.

  13. 160 BPM, for any others who are a little obsessive :)

    (My superpower is identifying 80BPM, so I guessed 160, but verified it anyway!)

  14. Surely this is Entrainment.  A very common (thankfully) occurrence in musical settings, also known as being in the groove.

  15. t all works because the total sum of the motions are added up and transmitted to each of the metronomes. The “out of phase” motions are suppressed while “in phase” ones are reenforced.  It’s also how sound is produced out of noisy excitation in acoustic instruments (e.g. wind, stringed instruments).  Indeed, if there were metronomes running at integral multiples of the most prevalent original speed, they too would synch up at their own rates. Anyone want to try that? 

  16. I am a little fed up with all of the anthropomorphization throughout this comment thread. They are metronomes doing what physics dictates they do given the circumstances. They are not soldiers or any other variety of people. Nor do they prove or disprove the existence of a human deity.

Comments are closed.