That's a question a fair number of CNET readers like to ask us, and while it's hard to give a definitive answer, Sennheiser's RS 185 model is certainly one of the better options out there at $280 (£230, AU$500).

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It's one of the middle models in Sennheiser's line of 2015 RF headphones that feature a new "class-leading, proprietary wireless link technology" that the company says delivers interference-free sound. Operating on the 2.4GHz band, the entry-level RS 165 model offers 30m (100-foot) range while the RS 175, RS 185 and RS 195 are rated as having a whopping 100m (about 330-foot) range.
You may get that range if you happen to be standing in an open field, but in our "real-world" tests in an open office as well as our New York apartments, the range was more like 20-30m (66 to 100 feet), and that range will be affected by what your walls are made of.
As far as the design goes, it's a comfortable closed-back over-ear design that does a good job of keeping sound from leaking out so you don't disturb someone sleeping nearby. But the headphones fit snugly enough that you may be forced to take some quick breaks while wearing them over the course of a 2-hour movie.

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