How to Buy a Bluetooth Headset or Car Speakerphone

The Specs Explained

As of this writing, the most current Bluetooth specification is Bluetooth 3.0 + HS. The new version of the spec allows the Bluetooth protocol to piggyback on 802.11 Wi-Fi when you need to take care of more-demanding tasks such as sending video from your camera to your TV.

Version 3.0 became final in April 2009, and products supporting the new spec are likely to reach the market by the end of 2009 or during the first quarter of 2010.

Bluetooth Standards: Old and New

Right now, we're seeing plenty of new cell phones, headsets, and car speakerphones that support the previous Bluetooth spec, Bluetooth 2.1 + EDR. In fact, you can expect to see products coming out well into 2010 that support version 2.1.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, for example, 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 3.0 + HS (High Speed, as in higher data rates): The new spec will clamp onto a Wi-Fi signal when handling larger chunks of data, so you can download scads of photos or synchronize your music library, for instance. This spec also promises to give you longer battery life, better security, and beefed-up power control. This should result in fewer instances of dropped connections in Bluetooth headsets and in-car speakerphones, for example. According to Michael Foley, executive director of the Bluetooth SIG, product categories where models will soon support Bluetooth 3.0 include smart phones, TVs, cameras, and PCs.

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/speakerphone don't need to be in direct line of sight to function properly and maintain their connection. Depending on your product's range, however, you can't roam too far. You can determine what a product's operating range is by looking at its classification. (This is applicable primarily to headset users; for speakerphones, range won't be as much of an issue since you'll have to keep your phone in your car.)

Bluetooth Class 2: On this kind of headset or speakerphone, you're limited to a working range of up to roughly 33 feet (10 meters). Most headsets and speakerphones 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 for Mono Headsets

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.

Profiles for Stereo Headphones

Most Stereo Bluetooth headphones also support the Hands-Free and Headset profiles, so you can make and receive phone calls with your Stereo Bluetooth headphones.

Advanced Audio Distribution Profile (A2DP): This Bluetooth profile enables your music source and the Bluetooth headset to stream music in stereo wirelessly.

Remote Control Profile (AVRCP): This profile enables your Bluetooth headset to control your music source wirelessly.

Profiles for Car Speakerphones

Car kits support the Headset and Hands-Free profiles. If your unit handles music, it will also support A2DP.

Object Push Profile (OPP): This profile enables sending data (or "objects"), such as virtual business cards or contact information. Car kits that support this profile can synchronize contact lists from the paired phone.

Phone Book Access Profile (PBAP): This allows the exchange of Phone Book Objects between devices. With a cell phone and a car kit talking nicely to each other, the speakerphone can display/announce the name of the person calling you.