Alerting in comparison: When to choose loudspeaker or siren?

Both make noise and both can be used to alert and inform. But which warning device makes sense when? We have briefly summarized the differences between loudspeakers and sirens:

Electronic sirens with Class-D Amplifier:

Ideal for

- outdoor areas

-for large-area public address systems

- For more demanding environments (terrain, buildings)

- High sound level of 109-123 dB(A) / 30m

- 360° all-round sound reinforcement

- independent of the power grid

- durable and low maintenance

- Voice announcements possible

Loudspeaker:

Ideal for

- indoor areas or

- targeted sound reinforcement in a small radius

- primarily in flat areas with little disturbance of sound propagation

- directed sound emission, i.e. for circular sounding one needs several sirens

- requires a working power supply

- lower sound level of usually 115 dB(A) / 1m, which corresponds to 85 dB(A) / 30m

Electronic sirens with Class-D amplifiers are therefore used to warn the population on coasts, in mountainous regions, in cities and towns, as well as in industrial environments, when larger areas need to be sounded, e.g. dams in the area of hydroelectric power or open-cast mining, or in extensive and unclear industrial environments - basically everywhere where fast, independent and large-area warning is required.