The dongle has a switch that allows it to function in either USB or Audio mode. In USB mode it is a fully-featured USB Bluetooth dongle - plugging it into my Fedora 9 install allowed me to see all nearby Bluetooth phones, computers and the headset. I haven't tried to see if I can get it to function as a Bluetooth audio device, but PulseAudio does apparently provide this. In Audio mode, it encodes input from the headphone jack on the dongle and sends it to the paired headset. This allows you to use other devices such as computers, phones and music players that don't have Bluetooth capability.
The headset supports the A2DP profile, which basically supports (reasonable quality) stereo audio over Bluetooth. The quality and the stereo separation are quite good and, although it might not be up to full studio monitoring quality, it is easily capable of delivering good quality audio for everyday use. It also supports the headset profile for phones that don't have A2DP capability, but the headphones don't have a microphone so you can't use it as a full headset.
The headphones are comfortable even after a couple of hours of use. They sit around the back of the head, and even for people who have a large skull (such as myself) they don't press in uncomfortably. They can also fold to be flat so they can easily fit in a pocket when not in use. The right speaker has a volume up/down control, a skip forward/back control (for phones that support such control) and a main button that can be used to turn the unit off and on and put it in pairing mode.
These are not a cheap device, at around $110. However, they are cheaper than many of the brand-name devices and are more comfortable than the BlueAnt X5s that I tried a while back. The larger speaker gives them a better bass response than smaller earphones and the lack of cord prevents all sorts of tangles and trip-ups. As someone who seems prone to turning away from the computer and pulling the earphones out of my ears by accident (and force), that's a good thing.
The major downside so far has been that, while they give perfectly good stereo audio between the encoder dongle and the headphones, the other two devices I've tried both have bizarre and annoying behaviour that makes them nearly unusuable. My phone, a Nokia 5310 XpressMusic easily capable of A2DP, will drop them down from A2DP to Headset protocol, detectable as a flat mono signal, and then eventually (in three tests) drop them altogether, often getting wedged on the song being played back (a different song each time which has played normally otherwise, so that wasn't the problem). This wedges the headphones too, requiring a little press of the hidden reset button with a handy bent paperclip. Don't have one to hand? Too bad. (Note to young players - the little hole beneath the reset button is actually to seal the rubber protector in place, and should not be poked into unless you want to put a damaging hole in the speaker diaphragm. And you don't.)
The computer was even worse. I got the laptop bluetooth working with the instructions at http://fedoraforum.org/forum/showthread.php?t=190468 and it all came through nicely. For two minutes. Then it went to Insanely Loud Mode. Once I'd dialled back all the settings in PulseAudio (which, for reasons as yet unclear, muted the audio completely at 60% main volume or 40% RhythmBox volume) it was listenable, although you could tell there was hard clipping going on somewhere before the volume reduction stage (audible as a 'crackliness' to the sound). Then, two minutes later, it dropped back to completely inaudible, and only by turning all the volumes up again did anything come out. Two minutes later it cycled back to insanely loud and kept doing this as long as I was prepared to put up with it. Adjusting the volume on the headset seemed to do little, although when I later connected it to my phone for a second test the volume on the headset was turned up very loud, and changing the volume on the headset altered the volume on the phone. So I assume that something in PulseAudio was 'helpfully' adjusting the volume, for reasons as yet unclear.
I haven't tested it with anything else that outputs A2DP via Bluetooth, so I haven't any other benchmarks to work against. But so far this is a device that works perfectly with its own adapter and appallingly with everything else; not a trait that endears it to me.
All posts licensed under the CC-BY-NC license. Author Paul Wayper.