Building a scalable Public Address solution with Zenitel IP Speakers

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Regardless of the size of your project, when you design a public address system, you need to make some decisions relating to the type of amplification, loudspeakers, and wiring convention to use.

A 100V line public address system is typically used in commercial premises or large areas for general announcements, public address, background music and fire/evacuation messaging. The 100V line system remains one of the best options for powering a large number of speakers across long distances and multiple zones. Due its cost effectiveness, passive speakers are often used in such installations, powered by PA amplifier that is usually installed in an equipment cabinet near the passive speakers.

Another way to deliver public address is by distributing audio over an IP network using active speakers (also known as IP or network speaker). Compared to passive speakers used for 100V lines, an IP-based active speaker has an embedded amplifier and can be directly connected to a standard Ethernet switch. One downside of an IP-based active speaker is the cost, due to additional components such as a built-in amplifier and Ethernet module. As a result, IP speakers are typically more suitable for smaller projects where higher zone granularity is needed.   

However, Zenitel's 30W IP speaker range delivers a cost-effective public address solution even for medium-sized projects, complementing its 100V line PAVA solutions.

With speakers delivering up to 123 dB of SPL, our IP speaker range provides clear voice messages over long distances using a minimal number of speakers. This makes our IP speakers a viable alternative for medium-sized projects when using a 100V line is not possible (example, a lack of equipment room for amplifier racks).  

For example, Zenitel’s IP horn speaker can deliver up to 123dB for speech applications, ensuring clear speech up to 32m from a single speaker. This makes it ideal for a train platform or for an industrial plant (assumed ambient noise – 80dB).

Delivering even SPL throughout the covered area

Such deployment with a single source of audio can work when an equidistant spacing is maintained between the speaker and spectators throughout the covered area. Otherwise, the speech pressure level will not be evenly distributed, resulting in overly loud messages in close proximity to the speaker.

With the ability to connect external passive speakers, our IP speaker range addresses this challenge by enabling spread out speaker setups. This helps create evenly distributed coverage. This is particularly useful for ceiling and cabinet speakers in indoor installations, where the distance between the closest and furthest spectators can vary significantly, leading to a noticeable deviation in loudness.

With such a distributed speaker setup, lower-power speakers are positioned closer to each area of the audience that requires coverage, ensuring a consistent sound pressure level (SPL) throughout the covered area. This is clearly illustrated in the following plots, which compare SPL distribution in a 10m x 10m room with a ceiling height of 3m between a single 30W speaker source and a distributed setup of three 10W speakers.

This distributed speaker system with IP speakers makes it suitable for covering a large area, while also allowing the sound pressure level to be evenly distributed.

Delivering a truly scalable solution by combining 100V line with IP speakers

Another key benefit of Zenitel’s public address solution is the ability to combine IP speakers with the 100V line Vipedia system, which provides a cost-effective PA solution regardless of the size of the project.

Public address deployments often require varying levels of audio zone granularity: large zones such as the concourse of a train station, medium zones such as retail stores, and small zones such as staircases or emergency exits. The PA system must accommodate these different zone sizes without significantly increasing the overall system cost.

While the 100V line Vipedia system is cost-effective for covering larger zones, IP speakers are an ideal fit for smaller and medium-sized areas such as staircases and retail stores. By combining the strengths of these two technologies, we provide a cost-effective PA solution suitable for zones of any size.

Conclusion

Whether it’s an emergency broadcast to evacuate your premises, a promotion you want to share, or regular daily in-store announcements, our combined 100V line Vipedia system and IP speakers offer cost-effective PA solutions that enable clear communication with your audience.

Learn more about Zenitel IP Speakers

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