Opera, symphony or chamber music - how can a venue ensure perfect acoustic conditions for all these performances? The Carmen active system enables real-time adjustments to the acoustical characteristics of a performance hall. Developed at the CSTB’s research laboratories, this innovative technology also adapts to small and medium-sized venues and rehearsal spaces with the CarmenCita system. Musicians and audiences are totally immersed in an acoustic space that offers the most intense musical experience.


Custom acoustics for major performance halls

Carmen adjusts a venue's acoustic characteristics to each type of performance, without requiring any architectural modifications other than the integration of cells into the decoration of the room. The system conforms to the natural propagation of sound within the hall and remains invisible to the audience and musicians.

  • The venue's natural acoustics are preserved, for a unique experience at every performance.
  • Easy-to-use technology.
  • Seamless architectural integration.
  • All-inclusive support from the engineers of the CSTB.

A proven electroacoustic technique

  • Respecting the orchestra's positioning and sound image.
  • Providing the venue with the greatest range of reverberation times (from 1 to 2.5 seconds).

Carmen consists of active cells hidden in the room's walls and ceiling. Each cell is composed of a microphone and a loudspeaker. The cells capture and replicate the sounds in real time, as if they were naturally reflected by the walls. The sound captured by a microphone is processed digitally and broadcast by the associated loudspeaker. Signals are processed locally, meaning that whatever is captured by a cell is broadcast only by that cell. In this manner, the acoustic characteristics of the walls and ceiling are virtually modified, while preserving the spatial and temporal consistency of the sound field.

As in a conventional performance hall, where sound is created through a series of successive reflections on the ceiling and walls, the Carmen system creates successive reflections on its cells to build the sound. The multiple cells interact with each other to enrich the sound field.

Natural acoustics

Natural acoustics

Acoustics optimized by the Carmen system

Acoustics optimized by the Carmen system

Customized service

The CSTB provides an all-inclusive service for the installation of the Carmen system. From the initial acoustic study to delivery, CSTB experts work in close collaboration with acoustic engineers, architects and project owners to ensure the results meet the highest level of expectations.

An acoustic analysis of the venue is carried out based on the 3D model of the room. It is used to define the number and position of cells and to demonstrate the system's benefits. Following the installation, the CSTB conducts all necessary adjustments and fine-tuning of the acoustic configurations and provides technical support.

In order to design each Carmen system, experts use professional software developed at the CSTB. The ICARE software, for example, predicts the acoustic descriptors of a performance hall, namely reverberation time, clarity and sound envelope.

Testimonial from a professional

“The installation of the Carmen system has totally changed the musical life of the Brighton Dome concert hall in particular and Brighton in general. The success achieved has far exceeded anything that anyone could have imagined possible. To the great delight of performers and the audience, making music here is now a great pleasure. In a hall which previously was a frustrating musical venue, we now have an acoustic which is lively, warm and exciting throughout the spectrum of orchestral sonority.”  Barry Wordsworth, conductor of the Brighton Philharmonic Orchestra (United Kingdom)

Théâtre des quinconces

Le Mans (France)

  • 825 seats
  • Volume: 4,700 m³
  • 32 cells
  • Reverberation time without enhancement: 1.0 second
  • 9 acoustic configurations, extending reverberation time to 2.1 seconds
Royal theatre

Norwich (United Kingdom)

  • 1,280 seats
  • Volume: 3,800 m³
  • 27 cells
  • Reverberation time without enhancement: 1.1 second
  • 6 acoustic configurations, extending reverberation time to 2.2 seconds
Grimaldi forum Salle des princes


  • 1,900 seats
  • Volume: 13,500 m³
  • 29 cells
  • Reverberation time without enhancement: 1.2 second
  • 6 acoustic configurations, extending reverberation time to 2.0 seconds

France and international

  • AYLESBURY WATERSIDE THEATRE Aylesbury (United Kingdom), 1,200 seats
  • PALACE OF ARTS Miskolc (Hungary)
    590 seats
  • THÉÂTRE MOGADOR Paris (France)
    1,800 seats
  • BRIGHTON DOME Brighton (United Kingdom)
    1,900 seats
  • SALLE MICROPOLISBesançon (France)
    2,000 seats
  • SALLE PRINCE PIERRE Grimaldi Forum (Monaco), 800 seats
  • FESTIVAL BERLIOZ La Côte Saint-André (France), 1,100 seats
  • LA RAMPE Échirolles (France)
    1,100 seats


The acoustic variability of small and medium-sized venues

The CarmenCita system offers modularity and high sound quality for all multipurpose venues and rehearsal spaces. Developed by the acoustic engineers at the CSTB, CarmenCita is based on the technology and know-how of the Carmen system. CarmenCita instantly adapts a venue's acoustics to its use by adjusting the reverberation time, tone balance and immersion in the music.

  • The natural acoustics are preserved, for a unique experience.
  • Easy-to-use technology.
  • A soundscape broadcast system designed especially for contemporary performances.
  • All-inclusive support from the professionals of the CSTB.

Come visit our showroom to appreciate how the system performs, by appointment, at the CSTB - 4, avenue du recteur Poincaré, Paris 16th. Contact : Jan Jagla - Tel : 04 76 76 25 94 -

An innovative electroacoustic technique

  • Homogeneous effect throughout the hall (regenerative system).
  • Acoustic presets on-demand.

The CarmenCita system uses active electroacoustic cells consisting of microphones and loudspeakers. These cells are distributed evenly throughout the ceiling and walls, so that the hall's reverberation time is controlled naturally. The CarmenCita processor generates acoustic and electronic matrices of natural sound propagation paths. During installation, an automatic adjustment procedure attunes the matrices to each acoustic preset, so that the CarmenCita system adapts precisely to the hall.

Professional support

The installation of CarmenCita in a venue does not require any major work or prior architectural modifications. Once in place, the equipment is fully integrated into the hall.

A complete acoustic study is conducted in cooperation with the architect for the positioning of the cells and their integration into the hall. The cells are wired and installed by a partner company specializing in the engineering and implementation of digital audio systems.

Next, the experts of the CSTB adjust the system and the various acoustic presets requested.

With a single click, an all-new sound immersion experience

The loudspeakers of the CarmenCita system can also be used as a soundscape broadcast system. Thanks to the uniform arrangement of the loudspeakers around the hall, the user can control the position of the sound sources during a performance, in real time. This spatialization system offers the audience an exceptional acoustic immersion experience.

CarmenCita is simple and user-friendly: a touchscreen remote control activates the system and presets can be switched from the touchscreen in the hall or on the stage by simply selecting the corresponding setting. The wireless touchscreen also provides user-friendly control over the functions of the spatial broadcasting system.