Wireless stereo headphones use different transmission technologies, depending on the headsets’ intended use. Bluetooth, infrared, and radio are options.
Until recently, wireless stereo headphones have been regarded as less portable and reliable than their corded cousins. But now there is a better selection of headsets that allow consumers to experience the music they want without tripping over cords – or disturbing others around them.
Wireless headphones can be grouped by transmission types. These include newer technologies like Bluetooth or Kleer, or more established types such as radio frequency or infrared. Each have their own unique characteristics.
Bluetooth Stereo Headphones
Bluetooth wireless technology has grown in popularity for headphones. It works with cell phones and music players, and is the best wireless choice for portable audio.
However, Bluetooth has disadvantages when used in stereo headphones. Sound quality is not as good as with wired headphones, and Bluetooth can only transmit lossy audio. Also, while there are an abundance of Bluetooth headsets available for wireless telephony (like at call centers), the selection of stereo models equally good at making calls and listening to music is smaller.
Consumers should make sure that they are using devices that are compatible with the current Bluetooth standard (A2DP). Pre-2009 iPhones, for example, do not support stereo Bluetooth.
Infrared Stereo Headphones
For home use, there are a variety of wireless headphone options. One uses infrared transmission, the same technology behind remote controls used for televisions and other audio-visual appliances.
Infrared headphones operate along a line of sight from the transmitter, so they get less interference and provide high-quality sound. However, listeners must stay in the same room — if not the same place — or risk having the IR signal drop.
Sony is the best-known manufacturer currently offering a line of infrared stereo headphones.
Types of Radio-Frequency Stereo Headphones
The oldest kind of wireless headphones technology transmits on conventional radio frequencies. RF headphones are usually among the cheapest, and have good-quality audio without the line-of sight limitation of IR types.
However, RF wireless headphones are prone to interference, even from common appliances. Adjusting the frequency is one way to combat this, and more expensive headsets may have auto-scanning features that do so for the listener.
One new type of wireless headphone technology that is getting experts excited is Kleer wireless. Unlike Bluetooth, Kleer transmissions channel CD-quality sound to wireless headsets. And unlike other RF headphones, they are less susceptible to interference.
Kleer wireless headphones aren’t widely available yet, though high-end headphones manufacturer Sennheiser has recently released a series of Kleer-equipped home theater headphones. TDK has released its own Kleer headset in Japan in March 2010, though there is no word yet on European or North American release.
How to Choose Wireless Headsets
Determining which type of wireless stereo headphones to buy depends greatly on where and how they will be used. But regardless of whether listeners choose radio, infrared, or Bluetooth headsets, it’s most important that the headphones sound good to – and fit comfortably on – the end user.