Courtesy of Michael Pettersen, Shure’s Director of Applications Engineering
The phone call began with, “I need a wireless transmitter that is water-proof. The venue is a U.S. Navy firing range and the wireless mic is used in all types of weather. What do you recommend?”
A wireless handheld cannot be made completely water-proof. Air must reach the mic element and that means there must be an opening of some sort. However, a ULX2 handheld transmitter can be made water- resistant by using two Shure accessories.
Accessory 1: A58WS Foam Windscreen. The foam cells are so small that rain droplets cannot easily enter the cells. Because of water’s surface tension, each rain drop prefers to remain as a whole structure and not divide into microscopic drops that could enter the foam cells. In addition, the meandering labyrinth of the open cells creates an arduous path for any water droplet trying to reach the mic element. Water-proof…no; water-resistant…yes.
Accessory 2: WA555 Grip/Switch Cover. The flexible plastic sleeve slides over the transmitter handle concealing the Power switch, Mode switch, Set switch, and LCD display. This sleeve inhibits water from entering the switches and display. Water-proof…no; water-resistant…yes.
Finally, there is the SM58 mic element. Dynamic mic elements, like the SM58, are immune to temperature extremes and humidity extremes. The same cannot be said for condenser mic elements.
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