Here’s a secret: on any given night in New York City and Brooklyn, groups of regular-looking people perform exceedingly difficult music in front of other regular-looking people, sometimes for one hour, sometimes for twelve. Often this music is being performed for the first time, and since much of it is aleatoric, or indeterminate, the audience witnesses a one-of-a-kind experience: completely unique, never to be repeated. It’s challenging to evaluate experiences like this exclusively in terms of the sounds produced, because the mere fact of their existence is simultaneously comforting and thrilling.

Monday night I trekked across Brooklyn to a venue tucked away on a sketchy side-street that smelled like cardboard. JackNY is one of many remarkable little venues that puts on such unique events; in this case, it was one night of the ongoing Composers Now Festival. Upon my arrival, I was delighted to see that the combined weight of the percussion equipment was probably heavier than the combined weight of the handful of audience members. At larger performing arts theaters, one can enjoy a sense of anonymity, but here, every listener becomes part of a larger entity – The Music – if only because of the effects of additional bodies on the acoustics. Throughout the evening, we would watch six different new music groups perform works by living composers.

We heard some of the composers explain their influences: “I wrote this after getting high and checking out the wall panels at the National Museum of the American Indian.” “I wrote boxesBoxesBOXES when I was moving and rediscovered all this random sh*t I owned.” “This piece is based on a true story: it’s about chickens who want to go to outer space. They have the knowledge but not the means. Then they find the means.”

We listened to Quiet City perform mesmerizing works by two of their members, Luke Schwartz and Steven Cohen. We stood on our chairs during a piece from Gelsey Bell’s new song cycle, which requires audience participation. During Elevator Rose’s set, we became intoxicated by an arrangement of Terry Riley’s A Rainbow in Curved Air that melted perfectly into Vasudevan Panicker’s Fix. The sounds were dense and wondrous, like getting lost in a safe place. During Paul Pinto’s “mini” pieces, the members of ThingNY catapulted a slew of notes and words from the stage and we laughed at snatches of the hysteria: “pack of manta rays” – “my weight is being watched” – “sit in my bed and masturbate and watch nine hours of Twin Peaks.”

Some of the sounds were painful or awkward or frightening. Sometimes the sounds surprised even their own composers, as with Kamala Sankaram’s piece for cello and laptop, which required a fearless level of improvisation from Anti-Social Music’s Pat Muchmore. Daniel Wohl’s Microfluctuations in Plainchant (for four saxophones and electronics), performed by the New Thread Quartet alongside four other pieces for saxophone quartet, was spellbinding. The microfluctuations of the title refer to the fluctuations in the frequencies after sending the chorale through an equalizer – what might happen if J.S. Bach had access to electronics and/or hallucinogens.

Many of us stayed all the way through to the final set. Iktus Percussion’s Cory Bracken scrambled around on the floor, laying out glass bottles and loop pedals and other accoutrements. A microphone dangled from a cord in his mouth as he performed his composition Real Numbers, during which he drummed on the bottles until they splintered into asymmetrical pieces and scattered across the floor. He used the feedback and a violin bow and various other objects to create haunting sounds and a frantic, memorable performance. Then three other members of Iktus (Chris Graham, Adam Forman, and Fred Trumpy) performed Iannis Xenakis’ Okho, for three djembés (an instrument described by the internet as “a rope-tuned skin-covered goblet drum played with bare hands”). Xenakis is widely considered a pioneer of 20th-century music because of his musical use of math and architecture, particularly stochastic processes. We could hear math being transformed into music during the intricately overlapping rhythms, which the three percussionists delivered with concentration and intensity.

The show wrapped up at nearly midnight, four and a half hours after it had begun. Exhausted and exhilarated, we tiptoed around the shards of glass on our way out.