Axis Mundi Sound Distribution System is an ever-evolving modular sculpture designed to emit, reflect, and direct (ultra)sonic waves to space from [single axis between the Heaven and the Earth](https://en.wikipedia.org/wiki/Axis_mundi). The singular axis with circular positioning of the audience reimagines the ways of sound distribution, challenging the typical hierarchy of stage performances. It also allows the performer to be in total control of the sonic experience, since it is self-sufficient and doesn't require external PA. It can even run on 12V batteries and solar power, making it independent from the electric grid as well. ![[amsds_live_2024.jpg]] *Photo by Anna Breit* Currently, the axis consists of 6 modules representing 8 separate channels of audio and 5 sources of light: - dual Cross made from fluorescent PMMA - three (ultrasonic) tweeters with reflective rotating plate for sound dispersion with 365 nm UV lights ("bat lure") - dual XLR light module - rotating ultrasonic parametric speaker - three "full-range" rotating speakers - subwoofer (two versions available, depending on use case) # バットディテクター バットディテクター (*Battoditekutā*—bat detector in Japanese) is a custom-made addition to the system that acts as an ultrasonic demodulator. Since the AMSDS is capable of distributing non-audible ultrasounds up to 40-50 kHz, ultrasonic demodulators can serve as audience-controlled spatial speakers in the space—creating an "invisible" thread between the performer and the listener, which becomes apparent once the device is correctly tuned. It creates a soft participatory situation where little to no-action is necessary, yet it allows for certain degree of expression via tuning the parameters of the demodulation and positioning. ![[bat_detector.jpeg]] The device features two controls: one for volume, which also functions as an on/off switch, and another for adjusting the demodulating frequency. This particular detector operates on the principle of [heterodyning](https://en.wikipedia.org/wiki/Heterodyne), where the incoming signal is multiplied by a high-frequency oscillator controlled by the frequency knob. When the oscillator's frequency roughly matches the range of the signal output by the AMSDS, the previously inaudible ultrasound becomes audible. On top of the バットディテクター you'll find a custom 3D-printed bat ear adapter using a modified [model by SageCettcle](https://sketchfab.com/3d-models/bat-ear-7373f8668af74d309d2c72ac6a650bc1). This acts as an evolution-designed horn/parabola for passive ultrasound amplification, the same way our ears are designed to boost certain frequency ranges. At the bottom, it has a 1/4-20" tripod mount for static (e.g. testing) applications.