By Andrew Liszewski
Yesterday Sony announced a couple of new cordless headphones for privately enjoying your home theater setup, and the MDR-RF4000K, pictured above, is definitely the more interesting of the two. The headphones use a secure digital RF signal which provides a decent range of up to 30 meters or around 100 feet, and their foldable design allows them to sit inside a slim storage case which also doubles as a charging cradle.
Sony’s headphone design team has never had a problem with styling, so the MDR-RF4000Ks look great as usual, and the 40mm long-stroke diaphragm ensures they should sound great to the consumer-level audience they’re targeted towards. A built-in NiMH battery is good for about 7 hours of continuous use on a single charge, but if they die in the middle of a flick you can switch to using a single AAA battery which is good for another 10 hours of listening pleasure.
Not pictured is the MDR-RF810RK headphones which Sony also announced yesterday. They’ll probably end up being the more affordable of the 2 (official pricing wasn’t released) since they use an analog RF signal instead of digital, but that also means you get a range of 100 meters or around 330 feet instead. They also feature a NiMH battery which actually provides 13 hours of use per charge, or about 28 hours when using a single AAA battery. Both headphones are expected to be available starting in April of this year.