Music and Public Address Systems

Music and public address systems are the turnkey installation of PA/VOX infrastructure that carries background music, announcement, notice and emergency evacuation instructions to indoor and outdoor areas of a building. In concert and conference halls, shopping centres, hotels, schools, hospitals and factories, it is essential that an emergency evacuation instruction be delivered intelligibly, like music, wayfinding and announcement. The system covers acoustic zone planning, loudspeaker-audio distribution, amplifier-rack allocation and integration of fire-announcement scenarios.

Architecture and Design

• Constant impedance vs 70/100V line: For large and distant distribution the 70/100V line (line transformer) is preferred; series zones are built with low loss balancing cable section-cost. 4/8Ω distribution for small rooms.
• Zone and loudspeaker plan: Independent announcement of each evacuation zone is mandatory; loudspeaker distribution-sound pressure level (SPL), speech intelligibility (STI) and overlap are computed. Outdoors: IP class and wind-noise compensation.
• Microphone-station: Desk microphone, calling station, priority matrix (emergency announcement interrupts everything) and matrix-switcher; music source management and programme timer.
• Integration: Automatic evacuation announcement with fire detection, coordination with automation and the camera centre; line supervision and fault reporting.

Testing and Commissioning

Commissioning includes zone-based SPL and intelligibility measurement (real speech test in noise conditions), loudspeaker line integrity and insulation (open-short line loop audit), amplifier power-heating test, priority-interrupt scenarios (music to emergency announcement), and battery-backup duration trial. The fire announcement scenario is verified in fire-authority-customer acceptance; the loudspeaker must also be designed to be intelligible for hearing-impaired persons (auditory-visual warning). The sound system is the invisible wayfinder of a building evacuation — if unintelligible, ineffective.

Maintenance and Legal Basis

In periodic maintenance line continuity, microphone-station function and emergency scenario tests repeat; loudspeaker-grille cleaning, rack ventilation-dust management and software-configuration backup are planned. Installation runs under Law No. 6331, the Fire Buildings Regulation (emergency announcement and intelligible evacuation instruction), the Internal Electrical Installations Regulation and accessibility rules; technically IEC 60849 and on the fire announcement side the TS EN 54-16 / TS EN 54-24 (voice control and loudspeaker equipment) rules. For acoustic zone planning, survey and quotation for your facility reach our team via the contact page; this service sits under our Low Current Contracting heading, planned integrated with our detection-periodic control services.

Acoustic Verification and Intelligibility

Design calculations are verified by field measurement: speech transmission index (STI), reverberation time and loudspeaker overlap maps are measured in the real space; in reflective halls, pools and production lines directional loudspeakers and delay lines enter the design, and visual alert devices join the zone plan for hearing-impaired users.