If someone ever criticizes you for being slightly off the mark or slow to react, tell them you’re modeling your actions after those in professional orchestras. Just look at this conducting:

Now look closer.

If you’re seeing what we see, then you might be left with the same question we have: Why does it seem like the orchestra is playing behind the conductor’s beat?

It’s not because these professional musicians can’t pay attention or are bad at counting — these aren’t wide-eyed children on the first day of school. What’s the deal? We figured that there would be no better person to explain this mystery than an actual conductor, so we turned to JoAnn Falletta, music director of the Buffalo Philharmonic and Virginia Symphony orchestras, to help us figure out what’s going on behind the beat.

Here’s the simple response: When an orchestra plays behind the conductor, it has the room to produce a more expressive sound. “It works so well because the musicians can take in a great deal more information before they play,” said Falletta. Waiting a tick allows the ensemble to take in the trajectory, speed and style of a conductor’s beat, which helps them determine what kind of sound the conductor is hoping to achieve. “It gives them a chance to prepare that sound. So the downbeat comes, and the sound opens after that.” The result? More beautiful music. However, orchestras don’t do this for the duration of a piece; the sound behind the beat is most pronounced in slower movements, and as the music gets faster and rhythms more complex, orchestras may tend to attack the downbeat along with the conductor.

If it seems like intentionally playing behind the beat while also producing a cohesive sound might be difficult, you aren’t mistaken. While many professional orchestras do play with a slight delay, things get a bit different when a guest conductor is involved, or if an orchestra has been assembled for a special occasion. Symphony orchestras involve scores of musicians on dozens of different instruments, and it takes time to develop a special bond that allows them to stay together while accounting for their designated conductor’s unique style. Take Fritz Reiner, who’s also the conductor you see in the first video of this article:

Falletta named Reiner as one of the first conductors she remembers hearing about in connection with this behind-the-beat phenomenon. A precise and fiery-tempered man who simply would not tolerate an orchestra that sounded out of sync, his orchestra had developed their own set of signs that would let them know exactly when to come in. Ditto conductors Serge Koussevitzky and Wilhelm Furtwängler, whose orchestras would play when the baton reached the third button of his shirt. It’s a learned behavior, and it can often give away who’s new in the group. “I know that when we have a new player who comes right out of conservatory,” says Falletta, “in that first rehearsal, they are the first ones to come in on that first note — because they aren’t used to [the delay].”

A 2014 article in Strad Magazine discussed the group behavior of orchestras in greater detail. Unlike Falletta, who stated that she and other conductors preferred when orchestras played behind the beat, the author of this Strad article maintained that conductors hated it. Whether or not it’s something universally loved or loathed is a different issue, but the piece did touch on a few interesting points about the relationship between individual members of the orchestra and the orchestra as a whole. Basically, the question is that of momentum — each musician has to anticipate when the orchestra as a whole will react to the conductor’s baton. A simple analogy in the Strad article, that many readers may already be familiar with, further illustrates this point:

“We observe a similar phenomenon waiting behind other cars at a traffic light. The light turns to green, but we cannot move until the cars in front of us have reacted one by one. Cars are not warned when the light is about to change; orchestras have the advantage of a preparatory gesture, but are still often late to the down beat. To come in accurately, a player must guess how late the group sound will be to the visual cue. The conductor must not react to the lag, but continue to beat steadily, placing each beat the same amount early.”

Here’s another question: If playing behind the beat leads to a more expressive sound, would the practice work with other, non-classical musical groups, like a big band or a wind ensemble?

“I don’t think it would work as well, because the phenomenon has its roots in the string section,” Falletta explained. Because string players tend to be in sync when they bow their instruments, playing behind the beat comes naturally to them. “They have time to say ‘OK, here we go’, and then get into the beat.” And that sound should have no point or edge; the music should just flow. Rigidly sticking to the downbeat makes the music a bit sharper, even when that isn’t the intention of the conductor (or composer, who knows?).

One last thing, and that’s bassist and educator Adam Neely’s own idea that explains the existence of this phenomenon.

Once during a recording session with a jazz ensemble and a string quartet, Neely noticed a surprising difference in the way classical musicians feel rhythm. He came to understand that while jazz (and rock) musicians seem to “internalize” the pulse of the music, classical musicians tend to react to it. That difference in feeling doesn’t mean that a musician who specializes in one type of music has a better grasp of rhythm than another. But, to Neely, that understanding of rhythm is what allows for musicians to approach music differently. Using concert footage of Leonard Bernstein conducting Mahler’s Fifth Symphony (the same performance included at the beginning of the article), Neely explains the concept of “phase locking,” and why the un-phase locked sound of a classical ensemble is barely perceptible (as opposed to that of a jazz band).

Whatever the reason, it’s safe to say that lagging behind yields great success on stage. Falletta is still fascinated by it. “The orchestras that have played together for some time just know how to do it. It’s very mysterious … I’ve seen European orchestras respond so far after the beat, that I have no idea how they know exactly where to place that.”

by James Bennett, II, via