Rugged wireless RF mic — workhorse on sets worldwide. Reliable, compact, minimal overhead for sound crew. Still industry standard despite newer competitors.
When you arrive on set and the sound mixer unpacks their wireless equipment, there's a high probability that one or two of these units are in the case. Sennheiser's EW series—especially the 570 and its relatives from the 500 series—are the workhorses in German-speaking countries and worldwide. They are not the most expensive, not the newest, but they work. That's the crucial point: they work reliably for eight, ten, sometimes twelve hours straight, even if the director is still shooting a final scene at 10 PM and the battery is already warning.
Practically, it looks like this: the sound mixer clips a wireless microphone onto the actor—usually a lavalier, sometimes a headset variant—and the receiver unit runs in the sound cart upstairs or in the assistant's pocket. The signal arrives cleanly, has levels you can adjust, and the dynamic range is sufficient for close-ups as well as for scenes where the performer walks through the forest. Frequency stability is the big plus: on a typical set with multiple cameras, LED rigs, walkie-talkies, and perhaps two other wireless systems, you don't have to worry about dropouts or strange interference—it used to be different, a real problem ten years ago. Today, it takes care of itself.
Another reason for their dominance: they are small, easy to hide under a shirt or jacket, and the batteries last the entire shooting day with normal use. No exotic special batteries, no complicated charging docks—just insert two AA batteries and you're done. This makes logistics on longer shoots considerably easier. The sound workflow doesn't suffer, and the costs for consumables remain low.
What they are not: a microphone for extremely loud live events or special studio situations. Their strength lies in robustness, reliability, and practical handling on the shooting day. For feature films, series, documentaries—anywhere you need to equip two or three actors with wireless and don't have time for troubleshooting—they are the go-to. They are the reason why many sound mixers have three or four of these sets in their inventory: they know they will be needed.