Evax 50W Red 16Z. The Bosch Voice Evacuation systems and expansion panels provide a variety of options that can be easily added to an existing fire alarm control panel system for area of assembly applications and for high-rise voice evacuation not requiring firemens' phones. Choose up to 2000 W of audio amplifier power to meet your speaker power requirements. You can supervise multiple zones through your choice of zone splitters. The EVAX50 provide 50 W of audio amplifier power in a standard-size enclosure.