Karlin Theatre

Located in Prague’s Karlín district, the Karlín Musical Theatre is the third oldest, second largest and widely considered the most beautiful theatre in the Czech capital. Famous for its staging of musical productions and operettas, the majority of the theatre’s shows are musicals.

The venue recently sought to upgrade its audiovisual technology to improve its performance and enhance its audience experience. As part of this update of the technical infrastructure, the theatre invested in Naostage’s automatic and beaconless tracking solution, K SYSTEM.

As the appointed integrator for the Karlín Musical Theatre’s AV modernisation, Pro Music was tasked with delivering a future‑proof solution that would elevate the venue’s musical productions while respecting the constraints of a historic building. Our process began with a full technical assessment of the theatre’s existing infrastructure, followed by an on‑site demonstration at the UFFO Theatre in Trutnov to validate the performance of Naostage’s K SYSTEM in a comparable spatial audio environment.

The theatre had recently invested in an L‑Acoustics L‑ISA configuration featuring nine frontal clusters to deliver high horizontal resolution across the auditorium. The next step was to ensure that audio objects could follow performers naturally and accurately across the stage. After a comprehensive market analysis, we selected Naostage’s K SYSTEM as the only tracking solution capable of meeting the theatre’s requirement to track up to 16 performers simultaneously, without compromising precision in a scenically complex environment.

Our installation combined one KORE AI processing server, two KAPTA multi‑spectral 3D sensors, and the KRATOS control software. The sensors were discreetly rigged above the stage—one beneath the central cluster and one at the proscenium—to maintain unobstructed coverage while preserving the theatre’s architectural integrity. KRATOS delivers real‑time XYZ positional data to the L‑ISA processor, enabling seamless translation into panorama, depth, and width parameters for each performer’s microphone feed.

This integration ensures that vocals and effects are localised precisely to the performers’ positions, maintaining a horizontal deviation of less than 7.5 degrees between visual and auditory cues. As a result, the audience perceives sound as naturally originating from the actors themselves, regardless of seating position—an experience unattainable with traditional stereo reinforcement.

The system’s automation capabilities significantly reduce workload for the theatre’s technical team, who manage six performances per week. Once calibrated, K SYSTEM operates reliably without manual intervention, even with elaborate costumes, dense scenography, and fast‑moving choreography.

The result is a cohesive, immersive, and highly intelligible audio experience that enhances every musical production staged at the Karlín Musical Theatre. According to the venue, the system “simply works”—delivering consistent, high‑impact results night after night.

Integrating Naostage’s K SYSTEM into the historic Karlín Musical Theatre presented several technical and architectural challenges that required careful planning and precise execution. As the integrator, Pro Music had to ensure that the tracking system delivered flawless performance while respecting the constraints of a protected, scenically complex venue.

One of the primary challenges was the theatre’s elaborate stage environment. With large moving set pieces, dense scenography, and performers wearing ornate costumes, the tracking system needed to maintain uninterrupted visibility and accuracy across the entire stage. To address this, we conducted extensive pre‑installation testing at the UFFO Theatre in Trutnov, validating K SYSTEM’s ability to track up to 16 performers simultaneously in a similarly demanding environment. This allowed us to fine‑tune sensor placement and confirm that Naostage’s computer‑vision‑based approach could withstand real‑world theatrical conditions.

Another major challenge was the need to integrate the tracking system seamlessly with the theatre’s new L‑Acoustics L‑ISA spatial audio setup. The system required precise XYZ positional data to drive real‑time localisation of audio objects. We overcame this by configuring KRATOS, Naostage’s control software, to deliver high‑resolution tracking data directly to the L‑ISA processor, ensuring perfect alignment between performer movement and audio rendering.

The theatre’s architectural heritage added further complexity. Sensor placement had to be discreet, structurally safe, and visually unobtrusive. We carefully selected mounting points—one KAPTA sensor beneath the central cluster and another at the proscenium—ensuring full 3D coverage without interfering with sightlines, lighting positions, or scenic automation. This required detailed spatial analysis and close coordination with the theatre’s technical and artistic teams.

Finally, the venue’s demanding schedule—six performances per week—meant the system needed to be exceptionally reliable and minimise operational workload. K SYSTEM’s automation capabilities proved essential: once calibrated, it operates autonomously, requiring no manual tracking adjustments during performances.

By combining rigorous testing, precise engineering, and sensitive integration within a historic space, we successfully delivered a robust, high‑performance tracking solution that enhances every production staged at the Karlín Musical Theatre.

The Karlín Musical Theatre project represents a landmark achievement in theatrical audio integration, combining cutting‑edge technology with the sensitivity required to work in one of Prague’s most historic and architecturally significant venues. As the integrator, Pro Music delivered a solution that not only modernises the theatre’s technical capabilities but fundamentally transforms the audience experience.

This installation stands out for its ambition and technical sophistication. The theatre required a system capable of tracking up to 16 performers simultaneously—dancing, singing, and moving through dense scenography—while maintaining absolute precision. Naostage’s K SYSTEM, powered by AI‑driven computer vision, proved to be the only solution capable of meeting these demands. Its integration with the L‑Acoustics L‑ISA spatial audio system enables seamless localisation of every performer’s voice, creating a natural, immersive sound field for every seat in the house.

The project also demonstrates exceptional engineering within a challenging environment. Installing multi‑spectral sensors discreetly in a protected theatre, ensuring unobstructed 3D coverage, and aligning tracking data with complex spatial audio parameters required meticulous planning and innovation. The result is a system that operates reliably across six performances per week, reducing technical workload while elevating artistic impact.

Most importantly, the installation delivers a profound improvement in audience perception. By ensuring that sound follows performers with sub‑7.5‑degree accuracy, the system creates an unprecedented level of realism and intelligibility. Viewers no longer hear voices drifting from off‑stage loudspeakers; they hear each performer exactly where they stand, enhancing emotional connection and narrative clarity.

This project exemplifies what modern theatre technology can achieve: precision, automation, artistic enhancement, and seamless integration within a historic space. It is a benchmark installation for the region and a compelling demonstration of how innovative tracking and spatial audio can redefine live performance.