Where I'm from, we have a saying: It's so simple that it's stupid. Basically, this means that something is so easy to understand that it's almost impossible for it to go wrong. That phrase pretty accurately describes the operation of the Kanex AirBlue. It only has one function--wirelessly streaming audio from a Bluetooth device to almost any audio player--and it does it well.
What does it do?
The Kanex AirBlue is simply a portable Bluetooth music receiver, or, as I like to call it, an audio bridge. After pairing with a A2DP-enabled smartphone or portable media player, the AirBlue is able to receive streamed audio wirelessly and output that same audio via a single 3.5mm analog audio connection. The device includes for this purpose an audio patch cable with 3.5mm male connections at both ends and a 3.5mm-to-stereo RCA audio cable.
On the unit's top edge is a single circular button that serves quadruple duty as a status indicator light, a pairing button, a power button, and a play/pause toggle.
Physically measuring 1.875 inches across and only about .25 inch thick with a matte black, soft-touch finish, the Kanex AirBlue is a stealthy little puck that is easily tucked into a pocket, hidden in a glove compartment, or nestled among audio equipment on a shelf. On the unit's base are four small circular feet that do a surprisingly good job of keeping the AirBlue from sliding about (although to be fair, the unit weighs next to nothing).
Holding the power button for a few seconds powers the unit on. While powered on, another long press puts it into pairing mode, in which the AirBlue can be discovered by a seeking Bluetooth device. Once it's paired, single taps activate the AirBlue's single implementation of AVRCP control: toggling playback and pause on the paired device's audio player.
Wireless play time can reach up to 10 hours on a full charge thanks to an internal rechargeable battery. The device receives power via an included Mini-USB cable that connects to a Mini-USB port located on its edge. The AirBlue can be used while it's charging.
What doesn't it do?
Because the Kanex AirBlue does not possess a microphone, the ability to connect to a microphone, or even compatibility with the Bluetooth Handsfree Profile (HFP), it cannot be used to add speakerphone functionality to, for example, a car stereo. The AirBlue is simply an audio bridge--the wireless equivalent of a 3.5mm-to-1/4-inch adapter you'd use to connect headphones to an older amplifier.
Also, there is no on-device volume control. Whatever goes into the AirBlue comes out at more or less the same level. Listeners will have to adjust audio levels on the source device or the connected audio receiver.
What is it good for?
At $49.99, the Kanex AirBlue is pretty pricey for a one-trick pony. For that MSRP, many people would probably expect a device with a few more basic features (for example, hands-free calling, internal volume control, and skip-forward and back buttons).
Then again, the Kanex AirBlue is one of those "less is more" devices that is defined by its simplicity. Whether or not it's worth the price on its tag will be determined by the number of uses that you can dream up for it, and I can think of a few interesting twists on its single trick.
Of course, the most obvious use is plugging the AirBlue into your home audio system to add Bluetooth playback from an iPhone, Android, or BlackBerry device. However, its small size and the fact that it can be easily adapted to 12-volt power with a simple adapter has me tempted to hard-wire the AirBlue semipermanently under the dashboard of the CNET test car to stealthily and wirelessly connect its audio system to a windshield-mounted smartphone (or tablet). At the gym, I was even able to pocket the ultralight AirBlue after plugging my headphones directly into it and stream audio from my nearby phone, which is too bulky to comfortably carry in workout clothes. Admittedly, that last use case is a bit of a stretch, but it was that sort of out-of-the-box use that made testing the AirBlue a fun endeavor.
If you've already got ideas for possible uses for the Kanex AirBlue bouncing around in your head, then the odds are that you've got the sort of imagination necessary to make this gadget worth checking out. While you're at it, why not share your ideas with the rest of us in the comments below?