Bluetooth headset buying guide - CNET Reviews

Most Bluetooth headsets have basic call features like the ability to answer and reject calls, last number redial, and so forth. Since sound quality is a priority with headsets, more advanced headsets like the Jawbone Era and the BlueAnt Q2 also feature dual-microphone noise cancellation for better sound quality. Some headsets boast resistance to wind-noise, which is quite a difficult task, and the Plantronics Voyager Pro Plus is one headset that performs that job admirably. Perhaps most interesting is the Motorola Finiti, which actually uses bone conduction to transmit so as to eliminate background sound altogether.

Another advanced feature is multipoint technology, which lets you connect up to two different devices at the same time. This is useful if you use one headset with two phones, for example. Headsets with multipoint technology include the Plantronics Savor M1100 and the Jabra Extreme. And speaking of innovative features, the BlueAnt Q2 is one of the only Bluetooth headsets to offer full voice command control. This meant we could say things like "Call Home" and if you've programmed the headset to do so, it'll do just that. The voice command on the Q2 is independent from your phone, so you can use it even with phones that don't offer voice dialing.

There are multiple versions of Bluetooth, and not all Bluetooth specifications are the same, so you might want to make sure your two chosen devices will work with each other. All of the newer Bluetooth versions are backward-compatible, however, so as long as you're using the more basic Bluetooth features, you won't have much to worry about. Most products currently work on Bluetooth version 1.1, which offers such basic features as voice dialing, call mute, and last-number redial.

In 2003, the Bluetooth Special Interest Group, a body that oversees the technology's development, released version 1.2 and rolled out version 2.0 a year later. Bluetooth 1.2 introduced new features to eliminate radio frequency interference through frequency hopping and added greater security to protect against snooping and tracking.

Most recent is the new Bluetooth 4.0 spec which major feature is Bluetooth Low Energy, essentially strong power management skills. Check out the various profiles and their features in the chart below.

Aside from these different versions of Bluetooth specifications, there are also quite a number of different Bluetooth profiles. A Bluetooth profile is an interface or a behavior through which different Bluetooth devices can communicate with each other. Both devices must support the same profile to communicate with one other in that way. The most common Bluetooth profile in cell phones is the Headset profile which supports the use of standard mono headsets for making calls. Here's a list of the more frequently used Bluetooth profiles in cell phones, as described by the Bluetooth SIG:

Advanced Audio Distribution Profile (A2DP)
Also widely known as the stereo Bluetooth headset profile, A2DP allows for a dual-channel audio stream through a stereo headset. A2DP is an especially popular concept with MP3 and music phones because it lets users listen to music wirelessly. It also can be used to make calls, and users can switch between music and calls at the touch of a button. 

Audio/Video Remote Control Profile (AVRCP)
AVRCP provides a standard interface to control TVs, hi-fi equipment, and so forth. This profile is used to allow a single remote control (or other device) to control all the AV equipment to which a user has access. AVRCP defines how to control characteristics of streaming media. This includes pausing, stopping, and starting playback and volume control as well as other types of remote control operations.

Dial-up Networking Profile (DUN)
DUN enables access to the Internet and other dial-up services over Bluetooth wireless technology. The most common scenario is surfing the Web from a laptop by dialing up via a mobile phone, wirelessly.

Hands-Free Profile (HFP)
HFP lets you use a gateway device to place and receive calls for a hand-free device. A typical configuration is in an automobile using a mobile phone as a gateway device. In the car, the stereo is used for the phone's audio and a microphone is installed in the car for sending outgoing audio of the conversation. HFP is also used for a personal computer to act as a speakerphone for a mobile phone in a home or office environment.

Synchronization Profile (SYNC)
The SYNC profile is used in conjunction with GOEP (Generic Object Exchange Profile) to enable synchronization of calendar and address information (personal information manager items) between Bluetooth-enabled devices. A common application of this profile is the exchange of data between a PDA and computer.

Object Exchange (OBEX) Protocol
OBEX is a transfer protocol that defines data objects and a communication protocol that two devices can use to exchange those objects. For Bluetooth enabled devices, only connection-oriented OBEX is supported.

SIM Access Profile (SAP)
SAP allows devices such as car phones with built-in GSM transceivers to connect to a SIM card in a Bluetooth-enabled phone. Therefore, the car phone itself does not require a separate SIM card.