The electroacoustic upgrade at the Shrine of Saint Charbel (Lebanon) resolves the severe intelligibility issues caused by its circular layout. Through the installation of 8 IONIC-V28 columns and RS 4-4000 amplification implemented by our distributor Eltek in Lebanon,uniform 360-degree coverage is ensured.

1. The Challenge: Parabolic Acoustics and 360-Degree Feedback

The Monastery Saint Maron, home to the Sanctuary of Saint Charbel where worldwide for its miracles, presents an extreme engineering challenge. Its circular floor plan, with the altar and open microphones positioned at the topological centre, creates a unique acoustic environment where the congregation surrounds the liturgy.

Historically, the venue suffered from severe deficiencies. The concave curved surfaces act as parabolic reflectors, concentrating acoustic energy into focal points that drastically degraded the Speech Transmission Index (STI) and severely limited the gain-before-feedback margin. After two years of rigorous auditing and design, our distributor, Eltek Lebanon, implemented a solution to definitively resolve these phase and directivity issues.

2. Directivity Control with the IONIC Series

To avoid the acoustic excitation of the curved walls and ceiling, Eltek’s technical strategy consisted of

 abandoning the point-source approach and adopting high-density column speakers. Eight IONIC-V28 column speaker were installed, forming a precise coverage ring.

• Phase Linearity: The 8 IONIC-V28 units form a precise coverage ring. Each column integrates eight 3″ neodymium transducers, operating as a coherent cylindrical wave source to minimise comb filtering.
• Vertical Axis Restriction: The vertical dispersion of the IONIC-V28 is limited to 15, the system concentrates sound pressure exclusively on the listening plane, preventing residual energy from reflecting off the ceiling back toward the central altar’s microphones.
• Constant Horizontal Coverage: The 100° horizontal aperture enables a controlled overlap, stabilising the Sound Pressure Level (SPL) consistently across the entire 360-degree congregation area.

3. Power Topology and Operational Stability

Powering this electroacoustic ring required a platform that would guarantee stable thermal performance and a continuous current supply for the neodymium motors.

Three RS Series amplifiers (RS 4-4000) were installed. This platform offers four independent amplification channels per chassis in a Class D topology. The RS 4-4000 units, which act as the system’s pure power engine, receive the time-aligned and equalized signal from an external DSP processor, ensuring the dynamic range necessary to reproduce the human voice without harmonic distortion.

4. Professional Rigour and Results

The Saint Charbel Sanctuary project proves that rigorous directivity control can overcome complex architectural acoustic limitations. Through the technical expertise of Eltek Lebanon, the sanctuary now benefits from a uniform and clear sound field.