![[horns in Slovakia.jpg]] My fascination with horns started very early—every child in Czechoslovakia that spent some time on a country side was very familiar with them. Used as part of a public announcement and warning system, they played a crucial role in the village soundscape. They often represented one of the most significant sonic events that could occur, alongside the familiar jingle of an ice cream truck. Usually the announcements started (and ended) with a song, to allow people to get into the best listening location. ![[horns in Slovakia 2.jpeg]] The content of the announcements was either about local festivity, special shopping opportunity (truck with meat arrived) or death. Regardless of the content, I really enjoyed how this sound system worked. How the sounds echoed through the village and mixed in with the usual sounds of circular saws and livestock, how one could adjust their experience by positioning themselves. There is something warming about the way these horns behave acoustically—they are purposefully tuned for maximum efficiency for transmitting vocal range. That means basically no bass or very high frequencies and a lot of distortion on top of that. I was lucky to not be a part of the generation that had to experience horrifying warning announcements through these systems, so I only have pleasant memories connected to the phenomenon (but I do record [public siren/announcement tests](https://archive.org/details/skuska-siren-2022) and did an [[Zvon II|artwork]] related to it as well). Around 2015 I did my first performances using public announcement system at the bus station in Topolčany, Slovakia. I was able to "hack" my way in and disconnected them from their original system. I connected a borrowed 100V amplifier (all these local PA systems work on [100V standard](https://en.wikipedia.org/wiki/Constant-voltage_speaker_system)) in place and was able to play a stereo version of my meadow field recordings as part of the "Lúky" project. ![[photo by Lucia Kovalova.jpg]] _Photo by Lucia Kovalova_ I started sourcing different kinds of 100V horns and modifying them to be used as regular speakers. I loved how efficient they are, which was especially useful in outdoor, off-the-grid setting. I started playing performances with them, many powered from a small 2A 12V lead battery and DIY class-D amplifier. They were all specifically composed with the sound of the horns in mind, embracing their imperfections. This eventually lead to shifting away from regular PA systems and performing through my horn speakers instead on a regular basis. One of those performances is also accessible on this website as [[Fontána Rodina]]. ![[Silent Night - photo by Libor Galia.jpg]] _Photo by Libor Galia_ I designed a small mounting platform that allowed me to create 4-channel sound distribution system that emitted sound from the centre of the venue. This challanged the traditional hierarchical arrangement where certain locations amongst the audience had poorer quality due to directional patterns of regular PAs. I usually performed by outputting 4 channels of mid-to-high frequency "voices" and one bass channel, that was played either by a small sub that I brought or the sub from the venue itself. Around that time, my friend Jakub from Mappa suggested adding a rotational element to the whole system. I was hesitant at first since I had no idea how to achieve tangle-free endless rotation. But after some research I discovered the existence of [slip rings](https://en.wikipedia.org/wiki/Slip_ring), which made the whole thing possible. ![[STUK Leuven.jpg]] _Performing at STUK, Leuven, Belgium_ To get the sufficient torque, I first opted for geared DC motors. Controlling speed of DC motors is quite easy (electronically speaking) and using a H-bridge circuit you can easily change the direction of the rotation. But the problem is the noise—DC motors are quite noisy on their own, and adding a set of metallic gears doesn't really help. This was especially an issue during the very quiet parts of the performance, one could hear the whining of the motor and the gears. In the end I have ended up using stepper motors using specialized stepper drivers, designed for quiet operation. This also opened the door for future sophisticated control patterns of the rotation—stepper motors can be very precisely controlled and that is the reason why they are used in CNC machines. ![[for_sphere_4.jpeg]] *Photo by Natália Zajačiková* A unique variation of my horn performances was site-specific [[Pre Sphéru (For the Sphere)]], using custom construction and manual positioning of the horns to achieve special acoustic effects. The last big performance using the horn system was in Paris in 2022 on a concert organized by the INA GRM. I was invited to create a new work with the [Acousmonium](https://en.wikipedia.org/wiki/Acousmonium). The lo-fi distorted horns were in stark contrast with the hi-fi speakers, but I think they shared the same desire for new, experimental ways of sound distribution within space. On that occasion, a video was produced, where one can see the speakers in their operation. <iframe width="1038" height="584" src="https://www.youtube.com/embed/t9C02qB7tL8" title="Jonas GRUSKA_Žaburina_FOCUS 2022" frameborder="0" allow="accelerometer; autoplay; clipboard-write; encrypted-media; gyroscope; picture-in-picture; web-share" referrerpolicy="strict-origin-when-cross-origin" allowfullscreen></iframe> In parallel to the horn system, I was already developing my [[Axis Mundi Sound Distribution System]]. Great deal of the technology used there originates from my horn experiments. Especially the knowledge of various slip rings and ways of achieving ultra-quiet rotation with stepper motors. ![[Sonic Acts – photo by Pieter Kers.jpg]] _First version of AMSDS in parallel with the rotating horns on Sonic Acts festival. Photo by Pieter Kers_ I still own a decent collection of horn speakers and think about their potential use in the future. If you are interested in my work with horns, I am open for invitations for galleries, sound installations, outdoor DIY events ꩜