In the ancient Javanese folk practice of jathilan, hypnotic rhythms push participants into altered consciousness. A gamelan troupe plays the kendang (a two-headed drum), a selompret (a double-reed wind instrument) and metallophones such as kempul (a set of gongs) while dancers ride hobby horses made of woven bamboo. As melodies escalate to powerful repetition and syncopation, dancers fall into a trance and spirits are believed to take over their bodies. During this period of possession, dancers perform dangerous feats without suffering visible harm. Examples include eating broken glass, walking on hot coals and even being run over by a motorcycle.

"Indonesian music has always been a way to communicate with gods, nature and the other worlds," said Rully Shabara, the innovative vocalist of Senyawa and Setabuhan, two giants in the country's experimental scene. "It's about moving beyond the material world and entering the spiritual world. When you're performing, you're transcending, you're forgetting the arrangements, composition and just feeling it."

Many of Indonesia's cultural and religious customs are based on animism, a belief system that encourages engagement with animals, ancestors and supernatural entities. To reach a level of trance that facilitates such exchanges, shamans typically depend on the pounding percussion and polyrhythmic peals of gamelan.

"Trance is the way to communicate to the sanghyang or God," explained Michael H.B. Raditya, a researcher on music and performing arts at Gadjah Mada University in the Indonesian city of Yogyakarta. "It's a phase between sentience and unconsciousness, life and death, human and God." During this state, Raditya said, people can transcend their physical and mental abilities thanks to drums, chanting and the shaman's mystical effects.

Inspired by ritualistic trance, Indonesia's contemporary musicians are reinterpreting the raw energy of centuries-old folk rites. Artists such as Senyawa, Setabuhan and Gabber Modus Operandi (GMO) use genre-defying production and energetic live performances to create what they call "sonic vibrations" rather than music. The result is a distinct breed of experimental sounds rooted in meditation but suitable for moshpits and festival stages.

Each act differs in style—Senyawa and Setabuhan are more avant-garde noise, while GMO leans towards happy hardcore—abut all three blend quintessentially Indonesian sounds with dark, industrial textures. This progressive vibe resonates deeply in Southeast Asia's largest economy, where heavy metal reigns supreme and even the current president rocks Napalm Death and Metallica T-shirts in public.

All three acts are "a modern translation of an ancient ritual, and at the core of this translation is the trance," noted Morphine Records founder Rabih Beaini, whose label features several Indonesian artists, including Senyawa. "All of them use a strong trance element in their music that's derived from Indonesian rituals. It's not about the genre or composition but the way they approach music as a personal and intimate experience."

GMO, a Bali-based duo consisting of producer Kasimyn and MC Ican Harem, is a study in modern Indonesian electronica. They furiously blend footwork and hardstyle with indigenous dance genres such as funkot, where high-octane basslines cross 200 BMP, the tight breaks and shouts of dangdut koplo, as well as penceng, which mixes fast beats with the music of Sumatra's Karo people.

Gabber Modus Operandi

In Bali, this type of Indonesian dance music is usually heard at small bars that are usually "pretty ghetto and full of gangsters," according to Ican. "This sound is usually rejected by Indonesia's cool kids who prefer Dekmantel and Boiler Room shows, but we're playing this vibe at Boiler Room now," he said with a laugh. "At drum & bass or house parties, people have certain dance moves, but with our kind of music, we see kids dancing differently."

Jathilan, also known as kuda lumping, is a leading influence on the duo. Kasimyn, who goes by Kas, doesn't sample any gamelan instruments in his production but he does employ gamelan scales such as pelog and slendro. "Growing up in Sumatra, my parents didn't allow me to see jathilan so that's why I was driven to it," he said.

Ican, meanwhile, submits himself to the music just like jathilan dancers yield to the spirits. Onstage, his body becomes a flurry of pulsating contortions as he screams and strips off clothing. (He unintentionally vomited at a Berghain performance earlier this year.) Even when performing in a small space, Ican finds a way to maximise every available centimetre. At Uganda's Nyege Nyege festival, he clamoured atop a makeshift stage and started madly gyrating, his thundering energy emboldening the crowd to dance even harder.

"I see what the crowd is feeling, then I act," Ican said. "If people are blankly staring, I'll do some silat [Indonesian martial arts] and make them afraid. If they look friendly, then I become an animal. I want the audience to feel the same as us."

The title of GMO's second album, HOXXXYA, which arrived on Shanghai-based SVBKVLT in August, is actually derived from a Javanese type of call and response music, Kas and Ican explained. "It involves a lot of shouting and audience interaction, the kind you feel in a punk show. Let's try finding that in our music, we thought."

While Senyawa and Setabuhan don't make dance music, their otherworldly mix of ambient, metal, hardcore and noise appeals to fans across the electronic spectrum. Senyawa, consisting of vocalist Rully Shabara and instrumentalist Wukir Suryadi, has become one of Indonesia's most valuable cultural exports. They combine throat singing, industrial drone, liturgical chanting and hand-made bamboo instruments to produce a sonic catharsis that will unnerve even the most jaded listeners.

Senyawa

Rully takes his cues from traditional Indonesian singing practices such as Java's nyinden and raego. Both are native to his home province of Central Sulawesi and usually performed for ceremonies such as harvests or marriages. The customs are deeply rooted in nature, something that's reflected in Rully's extensive vocal range, which includes wind-like howling and falsetto notes that resemble gentle bird calls.

"You cannot really pinpoint my singing, it sounds like a slow melody but it's mixed with many regional sounds," he said. "I never studied singing so I wanted to find techniques that I would be comfortable with."

Wukir, meanwhile, plays what he calls the "bambuwukir," an amplified zither he designed himself with metal and bamboo-fibre strings. Aside from generating eerie string notes, the instrument also doubles up as guitar and percussion. With the help of looping devices, Wukir draws out sludge-drenched chords, blackened doom notes and dissonant harmonies from this multidimensional tool.

"My awareness of playing music is not connected with any specific tradition," Wukir said. "Senyawa explores honesty of the soul, and playing music honestly is the key for me. If the listener hears something 'Indonesian,' I won't reject that claim, but I would ask the listener to first free the nature of their mind."

Unlike Senyawa, Setabuhan—one of Rully's many other bands—is more of a rhythm-based project centred around performance art. Mad drum beats from percussionists Ramberto Agozalie and Caesarking, in combination with Rully's double looped voice, create an immense soundscape that's as harrowing as it is contemplative. But listening to this three-piece outfit on headphones won't do them justice. Their live show features silat fighters who engage in free-form sparring to explore displays of aggression and physical contact.

A major element in Setabuhan's creative foundation is the healing ceremony known as balia, in which shamans invite spirits to cure individuals of disease and all those present fall into a trance against a steady buildup of gong and drum rhythms. A medicinal system native to the province of Central Sulawesi, balia is also seen as an act of worship, consecration, protection and sacrifice to supernatural powers. "Setabuhan deploys the rhythm and tempos in balia," Raditya observed. "They use the element of music to make audiences connect with balia's physical energy."

Setabuhan at CTM 2019 Festival Berlin

While Gabber Modus Operandi, Senyawa and Setabuhan each reference multiple elements of Indonesian folk history, this isn't always obvious. That's partly because the musicians aren't actively emphasising their cultural roots. None see themselves as torchbearers of Indonesian identity or curators of Indonesian folklore. Rather, they say their music is simply an improvised reflection of their surroundings.

"Like most Indonesians, I eat rice from morning to afternoon to night so my music is just an extension of what's around me," said Senyawa's Wukir.

"It's not our intention to be cultural ambassadors or anything, we just really dig the energy of Indonesian music, it's so wild," said Kas of GMO. "For our video 'Dosa Besar,' we cut everything that showed cultural costumes, we just wanted to show local kids on the streets wearing sneakers and black metal T-shirts."

"We're not promoting Indonesian culture, but creating something else based on our own ideas," Rully said. "The aim is to blur the lines of traditions where we cannot pinpoint where the music originally comes from."

The complicated nature of Indonesian identity works in Rully's favour. Home to over 17,000 islands, of which 6,000 are believed to be inhabited, the Southeast Asian archipelago boasts more than 600 ethnic groups. The country is too massive and diverse for just one national voice.

"Indonesia is so good at producing different styles of music because every region borrows from one another," Rully explained. "This regional mix is very important and partly explains why it's so difficult to say with confidence where a certain style originates from."

Despite their organic mentality, all three acts are highly aware of their music being exoticised by international audiences. None of them seek to live in the past or exploit folklore. Instead, they say the goal is to constantly refresh their approach to music-making and composition through experimentation.

According to Raditya, each group pairs traditional idioms with modern developments in a way that leaves the ancient beliefs open for reinterpretation.

"The singular thing about these musicians is that they truly own their sound," said Morphine Records' Beaini. "It's not rock or modern. It's not music coming from the East to please the West. It's something they crafted and it represents them, their life, experiences, culture and stories."