Physical Review Letters, volume 110, article 228701, published in 2013. Four researchers at Cornell, Jesse Silverberg, Matthew Bierbaum, James Sethna and Itai Cohen, took video of crowds at heavy metal shows, tracked the motion and published the results in one of the most demanding physics journals there is.
What they found is that a mosh pit is a disordered gas and a circle pit is an ordered vortex, and that both fall straight out of the same simple flocking simulations used to model birds and bacteria. Nobody in the room is coordinating anything. The behaviour emerges anyway, from a few hundred people following a couple of local rules each.
So the first thing to say about the pit is that it is not chaos. It has never been chaos. It is a physical system, and the people inside it have known that for forty years without needing a journal to confirm it.
Where the thing came from
It started as the pogo and it turned into something else in southern California around 1978, in hardcore punk rooms, where the style was to move in a circle swinging your arms and colliding with whoever was next to you. From there it went to Washington, to Boston and to New York, and each city bent it: Boston added punching, New York went theatrical with the arms.
The word itself is a mishearing, and a good one. H.R. of Bad Brains used to shout "mash it up" from the stage in 1979 and 1980, in a Jamaican accent, and American audiences heard mosh. Stormtroopers of Death put "Milano Mosh" on a record in 1985 and fixed the spelling. Anthrax took it to a much larger audience two years later with a song built around the word, and by the end of the eighties a term coined by accident in a Washington hardcore club was in general circulation.
Death metal inherited all of it, then changed the engine.
The forms, named properly
People outside the room see one undifferentiated mass. Inside it there are distinct things happening, and each one has its own trigger in the music.
- The pit. A churning open space in the middle of the floor, bodies colliding and rebounding. This is the gas state in the Cornell paper.
- The circle pit. Everybody running in a ring, centre left empty, direction agreed by nobody and settled within about four seconds. The vortex state. It opens on fast tremolo picking and blast beats.
- The wall of death. The floor divides into two halves that back away from each other and then run together on a cue from the stage. Sick of It All, formed in Queens in 1986, are credited with making it standard, although Lou Koller said plainly in 2019 that the band did not invent it and only brought it back.
- Two stepping and windmilling. Inherited from hardcore, done on the beat rather than into somebody, and generally kept to the edge of the pit.
- Stage diving and crowd surfing. The oldest elements, and the two most likely to be banned by a venue.
The breakdown is the instrument
This is where death metal contributed something the punks did not have. New York was the crossover point, the city where hardcore rooms and death metal rooms shared an audience, and what came out of it was the breakdown.
Suffocation recorded Effigy of the Forgotten at Morrisound in Tampa in June 1991 with Scott Burns producing, on a budget of five thousand dollars, and Roadrunner released it on 22 October. The opening track, "Liege of Inveracity", carries what is generally identified as the first slam riff in death metal, and an entire subgenre grew out of it.
Understand what a breakdown does mechanically. The tempo halves and the crowd's collective velocity doubles, which is the only trade in music that is made on purpose and works every single time. A blast beat is too fast for a body to answer with anything except running. A half time riff hands the floor a beat it can actually hit, and four hundred people hit it together.
The tempo halves and the crowd's collective velocity doubles, which is the only trade in music made on purpose that works every single time.
The rules, which are real and unwritten
Every functioning pit runs on the same short list, taught by example and enforced by everybody at once.
Somebody goes down, the people nearest stop and pick them up, and that happens before anything else. You do not swing at a person standing still, and the ring of people at the edge facing inward are not participants, they are the container. Glasses, phones and anybody obviously smaller than the average get moved out. If you cannot take a hit, you stand behind the ring, and nobody thinks less of you for it.
None of this is written down anywhere, and none of it is negotiable. A room where the rules are known is far safer than its appearance suggests. A room where half the audience has never been in a pit before is genuinely dangerous, and every regular can tell which kind of room they are in inside about ninety seconds.
The pit is not the same in every room
Subgenre changes the floor more than most people expect, and you can tell which style a band plays from the back of the room with your eyes shut.
Old school death metal, with the tempo sitting in the middle and the riffs rolling, produces the classic churn: a wide open circle, people moving through each other, everybody upright. Grindcore produces something shorter and more violent that stops dead every forty seconds because the song has ended, and the floor spends half the set resetting. Brutal death metal and slam produce almost no running at all, because the music is built out of half time chugs, so the room goes low and heavy instead and moves in place. Technical death metal, at the far end, frequently produces a floor of people standing completely still watching the guitarist's left hand, which is its own kind of tribute.
The one genuine argument inside the culture is about hardcore dancing carried into metal rooms. Windmilling arms and spin kicks are done on the beat rather than into another person, which works in a room that knows the form and is dangerous in a room that does not, because the swing has a radius and the bystanders have not consented to being inside it. The rule against hitting somebody who is standing still exists precisely for this, and it is the one rule that gets broken often enough to start fights.
The other constant is the barrier. Everything at the front is managed by security lifting bodies over a steel rail, and the reason venues ban stage diving is not squeamishness, it is that the person underneath the diver has no way of seeing him coming.
The part that is not a joke
People have died at concerts, and the record should be stated plainly rather than argued around.
A man died of crush injuries at a Smashing Pumpkins show in Dublin in 1996. Jessica Michalik died of asphyxiation at the Big Day Out festival in Sydney in 2001, during a set by Limp Bizkit. Both were crush incidents in very large crowds at mainstream events, which is the pattern almost every time: the danger is density and a barrier, not a pit.
Some musicians will not have it at all. Fugazi stopped shows to speak directly to people who were hurting others. Manowar have halted sets over it. Those are honest positions and they have been held for decades.
The defence of the pit is not that it is harmless. It is that it is consensual, bounded, and policed by the people inside it, and that a death metal floor is one of the few places in public life where several hundred strangers will physically catch somebody they have never met.
Why this music in particular
Because the records were built for it. Everything that surrounds them, the artwork, the tapes, the magazines and the arguments, is what surrounded the records, but the floor is where the design shows. A death metal song is arranged in tempo blocks that each ask the room for a different thing, and a band that cannot sequence those blocks will empty a floor in two songs no matter how good the riffs are.
The last piece of that design is the one people ask about before anything else, which is the voice sitting on top of it and why it sounds the way it does. That is why Death Metal Vocals Sound Like That, and it turns out to have as much mechanism behind it as the pit does.
