Tetra Sonus
Advanced Quadraphonic Sound for Deep Listening
Tetra Sonus is a series of quadraphonic listening sessions designed in synergy with sonically unique spaces throughout the world. Each edition presents newly commissioned pieces or significantly adapted works of historic value, produced using advanced spatial audio technology for presentation as a shared listening experience.
The series premiered at the Feuerle Collection, Berlin, with works by Sofie Birch and Kyoka. Additional editions are in development for architecturally distinctive locations across Europe and Asia.
System
VVSSL operates a proprietary full-spectrum quadraphonic sound system, designed and configured for architecturally unique spaces. Built for precision and portability, the system is deployed exclusively for Tetra Sonus presentations and commissioned listening experiences. Each installation is tuned to its environment, transforming the acoustic character of a space into an integral part of the deep listening experience.
Tetra Sonus Selected Artists
Kyoka
Kyoka is a Japanese-born, Berlin-based sound artist whose compositions blend irregular rhythms, fragmented melodies, and tonal contrasts that shift between intensity and restraint. As the first solo female artist on the Raster-Noton label, she has developed a singular approach to electronic music that resists genre specificity while remaining emotionally direct. Her work often draws from research into auditory perception and the psychological effects of sound, creating listening experiences that are both disorienting and deeply focused. Her research into the field of sound and its connection to human understanding will be ever present in her commissioned piece for Tetra Sonus.
Sofie Birch
Sofie Birch is a Copenhagen-based composer, multi-instrumentalist, and vocalist whose ambient works combine electronic hardware, acoustic instrumentation, and field recordings to create rich, layered soundscapes. Her practice is rooted in a deep interest in the therapeutic potential of sound, often drawing from principles of sound healing and somatic awareness. Birch’s compositions unfold slowly and sensitively, inviting the listener into states of introspection and calm. Her live performances often incorporate scenographic elements, creating immersive environments where sound, space, and subtle movement form a cohesive sensory experience.
RESONANT DRIFT
A deep listening installation by Kyoka
In Resonant Drift, Japanese electronic composer Kyoka explores the space between sound and the unconscious. Inspired by neuroscience, experimental music, and architectural acoustics, the work investigates how sound and human perception shape and respond to each other.
Presented as part of the Tetra Sonus Listening Sessions, the installation unfolds within the quiet and textured space of The Feuerle Collection. Kyoka’s four-channel composition engages in a subtle dialogue with the sculptural and architectural elements of the space, inviting an inward drift.
A deep listening installation by Sofie Birch
Originally composed for a 32-channel spatial audio system with support from Strøm Festival (2022) and mixed in collaboration with Alfred Bundgaard, Lolupupi Kutiku is a sensorial landscape—at once tender, mysterious, and immersive. Reinterpreted here in a quadraphonic sound by Sofie Birch, the work is part of the evolving Tetra Sonus Deep Listening Session program.
Drawing on her background in sound therapy, Birch treats composition as a healing architecture—conjuring intimate inner environments that challenge the boundaries between city, body, and natural world. Here, listening becomes an act of restoration. Lolupupi Kutiku asks: What is inside you when you truly listen?