A Bluetooth headset can set you free. When paired with a compatible cell phone, a Bluetooth headset allows you to make calls without having to hold the phone in your hand. And Bluetooth headsets are more than just a convenience--in some places, using one is the law. It may be illegal for you to use your cell phone without a headset while driving.

Even if you live in a state where it isn't a violation to talk on a cell phone while driving, you should invest in a headset anyway. Using a Bluetooth headset can be a liberating experience.

The Big Picture
It's a Bluetooth jungle out there. Expect to find a large number of headset manufacturers, different designs, and a wide range of prices. Call quality can vary considerably, too. more

The Specs Explained
Unclear about the performance that a given headset is supposed to deliver? Confused by the jargon? We explain the terminology. more

Bluetooth-Headset Buying Tips
Do your homework to ensure that you choose the right headset for your style, the first time around. Remember that one size does not fit all. more

For Additional Information
If you're ready to research Bluetooth headset models or to learn more about selecting a cell phone, check out the following PCW resources.

The Big Picture
Bluetooth technology lets two devices talk to each other wirelessly over low-frequency radio waves in the 2.4-GHz range. Both devices, such as a phone and a headset, must be Bluetooth-enabled.

The devices connect through a process called pairing. To start pairing between a headset and a phone, you use your Bluetooth phone's interface, making sure that the headset is turned on and in pairing mode. The phone then searches for and locates the headset. To establish a connection, depending on the version of Bluetooth that your phone and headset support, you may need to enter a PIN on your phone's keypad; afterward, your phone will recognize the headset. And, you hope, the devices will talk--nicely--to each other. (For more details about Bluetooth specifications, see "The Specs Explained.")

Manufacturers and Flavors
You'll encounter a huge variety of Bluetooth headsets on the market. You can find models from traditional headset makers (such as Plantronics), cell phone manufacturers (such as Motorola and Nokia), and Bluetooth-only companies (such as Aliph, which offers the Jawbone). At the low end, Bluetooth headsets start at about $25; at the high end, you can expect to pay at least $100 to $150.

As far as design and style go, take your pick: over-the-ear or earbud (some do both); silver, gold, candy-colored, black, or gray; sleek or boring; bulky or discreet; long or short; lightweight or superlight. Over-the-ear (aka ear-hook) headsets can have wide, loopy hooks or thin, narrow ones; they can be plastic, rubberized metal, or leather, too. Some headsets have earbuds that are completely round, while other buds have tips that protrude.

Headset makers handle the arrangement and feel of the function buttons differently, too. Some buttons are recessed, others are raised, while still others are flush with the headset's surface. Some buttons sport notches or markers; others lack indicators entirely.

Performance and Packages
We'd like to say that call quality through a Bluetooth headset is consistent and comparable to--or better than--what you get from a cell phone on a good day. But it isn't. In our testing, even the best-sounding headsets overall still had their off moments, producing faintness, voice distortion, echoes, and disappointing background-noise cancellation, for example.

When you're considering battery life, expect to see a wide range. Depending on the headset manufacturer, advertised talk times start at about 4 hours and go up to 9 hours. Standby times start at about 100 hours and extend to about 250 hours.

In a perfect world for headset makers, people's ears would be identical. They aren't, of course, and that's why we prefer that headset bundles include multiple options to help you find a good fit. Some manufacturers are generous with their goodies, providing small, medium, and large earbuds, along with an additional ear hook or two. Others give you an AC charger and a user guide, but nothing else in the box.

The Specs Explained
As of this writing, the most current Bluetooth specification is Bluetooth 2.1 + EDR.

That spec became final in July 2007; more than a year later, we're seeing only a small number of headsets (and phones) that support the new spec trickling into the market.

Bluetooth Standards: Old and New
Most headsets available now support a previous version of Bluetooth; even after the release of 2.1, many new headset models support 2.0. The good news is that all of the more recent Bluetooth versions are backward-compatible. So if your phone supports version 2.0, but the headset you choose supports 2.1, the two devices will still work together. You just can't take advantage of 2.1's enhancements (such as faster pairing), as both devices must support the newer spec for the added features to have effect.

Development and licensing of the Bluetooth specs are the responsibility of the Bluetooth Special Interest Group (SIG), a trade association that consists of companies in various industries, including telecommunications, computing, automotive, and networking.

Bluetooth version 2.1 + EDR (Enhanced Data Rate): The latest version of Bluetooth offers beefed-up security, and it's designed to let you breeze through the pairing process without the need to enter a PIN. All you have to do is turn on the headset and then select 'Add Headset' from your phone's menu; your phone and headset will find each other and connect through an encrypted link.

Bluetooth version 2.0 + EDR (Enhanced Data Rate): Version 2.0 (released in 2004) requires you to go through a multistep procedure to pair a headset with a phone. With the headset turned on, your phone must search for and recognize the headset; and then to connect to it, you have to punch in a passkey (typically four zeros).

The "EDR" portion of the spec means faster transmission speeds and lower power consumption. For exhaustive details about the Bluetooth versions, check out the Bluetooth SIG's Specification Documents.

Working Ranges
Your paired Bluetooth phone and headset don't need to be in direct line of sight to function properly and maintain their connection. Depending on your headset's range, however, you can't roam too far. You can determine what a headset's operating range is by looking at its classification.

Bluetooth Class 2: On this kind of headset, you're limited to a working range of up to roughly 33 feet (10 meters). Most headsets today belong in this group.

Bluetooth Class 1: Headsets that meet this spec offer a range of up to 328 feet (100 meters). Models supporting this range are far less common. Only one headset we've seen lately, the Callpod Dragon V2, is categorized as Class 1.

Profiles
A Bluetooth profile is a spec that defines the standard capabilities of a Bluetooth-enabled device. For any Bluetooth headset you consider, look for the following two common profiles in the product's specifications list.

Headset Profile (HSP): You can talk on the phone through the headset, and you can do basic things such as accept incoming calls, hang up, and adjust the volume.

Hands-Free Profile (HFP): This profile enables you to talk on the phone and operate it. For example, you can redial the last number, handle call waiting, and dial by voice.
Bluetooth-Headset Buying Tips
The last thing you want is to buy a Bluetooth headset and discover that it's a bad match. Then it ends up buried in your bag or in your glove box, unused. To avoid that scenario, keep these tips in mind as you shop around.

Factor in your environment: If you talk on your cell phone a lot in your car or on public transportation, or in other potentially noisy surroundings, look for a headset with a good reputation for noise cancellation. (A headset alternative for heavy in-car phone use is a Bluetooth car kit--essentially a speakerphone for your cell phone.)

Try different designs: Ear hook or earbud? It's hard to know what will feel comfortable until you try both types. If you wear glasses, remember that using an ear hook can be a real pain--your glasses and headset compete for space in the same spot! Ask friends and colleagues if you can try wearing the models they own. (For hygienic reasons, and as a courtesy, you should use new ear covers, so that your friends won't be offended when you wedge their headsets into your ear canal with reckless abandon.)

Determine your usage habits: If you're the type of person who will pop a headset on and off a bazillion times a day, consider a hookless headset that goes straight into your ear--no over-the-ear jockeying or two hands required. On the flip side, if you plan to leave a headset in your ear for extended periods of time, think about whether an ear-hook headset would be more your style. The design might make the fit more secure.

Figure out your style and preferences: A shiny silver Bluetooth headset may look appealing in its fancy packaging on the store shelf, but how will you feel when you wear it? Visualize the contraption on your ear. Remember that whatever headset you choose, it's visible, and like eyeglasses, it will be part of your face.

Ask around for feedback: While you're taking your friends' headsets out for a spin, ask them how happy they are with the performance. How good is the call quality? Can you depend on it for business calls? How frequently do people on the other end complain about voice distortion or annoying background noise? Do the advertised talk and standby times live up to the maker's claims? After a day in the office with the headset stuck to your ear, do you feel any soreness?

Confirm compatibility: Make sure that the headset you plan to buy will support the cell phone you own; some Bluetooth headsets do not support all Bluetooth phones. Many headset manufacturers provide a compatibility list on their Web sites, where you can search for your phone's make and model.

Be prepared for a no-return policy: Depending on where you buy, you may not be able to get a refund for a headset you don't want. Whether it's an online store or a brick-and-mortar outfit, the seller you buy from might not accept returns of opened headsets for sanitary reasons. Find out what the restrictions are before you commit.

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