The Jawbone Icon HD + the Nerd ($139, direct) are one heck of a pair. The Icon HD is a supremely capable, high quality Bluetooth headset, while the Nerd is a companion USB dongle for instantaneous, wire-free audio on any PC or Mac. For users that want an easy way to connect a headset to both PCs and phones, this is a great choice. But if you can do without the Nerd, you'll getter slightly better sound quality from a couple of other headsets for a similar price.

Design and Call Performance
Just like its predecessors in the Jawbone line, the Icon HD has style to spare. It's the same exact size as the previous Jawbone Icon ($99, 4 stars), measuring 0.7 by 1.8 by 0.9 inches (HWD) and weighing just 0.3 ounces. The two-paneled, textured front is a rich shade of navy, while the rest of the headset is black. There's a power switch on the back, between the Voice Activity Sensor, which controls the Icon's noise cancellation, and the ear tip. Powering the device on or off is instantaneous, and the location of this switch helps to avoid any accidental power-ups. There's a multi-function Talk button on the back edge of the headset.

The HD comes with seven different sets of ear tips, including three that sit in your ear, and four that use an ear hook. There's also an AC charger with a 4.5-inch micro-USB cable. The default ear tip fit me securely, and I wore the test unit comfortably throughout a day of testing. When you aren't on a call, you can get an audible battery alert by tapping on the headset's Talk button. A full charge takes about 90 minutes, and I got 4 hours 56 minutes of talk time, which is great for such a tiny headset.

The Icon's handsome styling translates to the Nerd, which shares the same textured detailing. It looks like an ultra-tiny thumb drive. At just over an inch long, though, it can be easy to lose if you're not careful. After you plug it into a PC or a Mac, you press a button on the Nerd for three seconds to enter pairing mode. Turn on the HD while holding the Talk button and the two devices will automatically sync with one another; once synced, there is no need to repeat this step again.

Call quality is great. Much like the excellent Jawbone Era ($129, 4.5 stars), calls sound clear, rich, and full of bass. Volume goes incredibly loud, too, so you won't have trouble hearing anyone indoors or out. The Icon HD's adaptive volume does an especially nice job of balancing earpiece volume with background noise when you're outdoors. There were no clicks, pops or hissing sounds in my tests, either. But while sound quality is excellent overall, it still isn't quite as sharp as on the Plantronics Voyager Pro+ ($99, 4 stars), though this will not bother most users.

Transmission quality is superb. Calls made over the Icon HD sounded smooth and natural on the other end, and noise cancellation is strong, thanks to Jawbone's NoiseAssassin 2.5 noise cancellation technology. I did experience some slight wind noise, which we also saw on the Era, but no one's going to have trouble hearing you clearly.

Jawbone claims the Icon HD's speaker is 25% larger than the speaker found in the original Icon. This resulted in great sound quality for music, podcasts, and stereo-over-mono, which makes this one versatile headset. Compared directly to the Era, though, streaming A2DP content over the HD sounds a touch muddy. Still, it's very listenable.

The headset has good range, too. I cleared about 35 feet before call reception started to break, and almost as far before music began to drop.

Connect Almost Anywhere with the Nerd
If you just want a great Bluetooth headset, buy the Era. The real reason to get excited about the Icon HD is the Nerd. After pairing the HD to the Nerd, you simply plug it into a USB port on any PC or Mac for instant, wire-free USB audio streaming. Why is this necessary when you can just connect the HD via Bluetooth? Many PCs don't have Bluetooth, and even if you do, Windows' Bluetooth UI can be troublesome and temperamental. The Nerd requires no drivers or software; it's a one-touch solution.

I loaded up a live audio stream from WNYC.org, which began to play through my laptop's built-in speakers. I then plugged the Nerd into a free USB port, waited a few seconds for it to be recognized, and the audio was instantly ported over from my laptop speakers to the Icon HD. The Nerd worked similarly well on a MacBook Pro, though I had to pull down the Sound menu to switch the output over to the Nerd. 

Apps, Android Companion, and Conclusion
As with the Icon and Era, the Icon HD runs "apps." There still aren't many available, though right now you can choose from a plethora of audio apps with new alert voices, as well as reconfigure the headset's button to dial special services like Free 411 (or paid 411, for that matter). There's no accelerometer, unlike on the Era, so you can't do things like shake the HD to make it enter pairing mode.

When paired to an Apple iPhone 4 ($199, 4 stars), a battery indicator appears in the top right corner of the screen to indicate the HD's battery life, which is helpful. There's also a new version of the Jawbone Companion for Android phones available to download from the Android Market, which currently supports a number of newer Android devices. I tried it out on a Samsung Droid Charge ($299.99, 4 stars). The Companion gives you some advanced functionality, like a battery life and connection status indicator at the top of your screen. You can choose to have the headset whisper reminders for upcoming events based on your phone's calendar; it's a little creepy, but it works well. You can even program the headset to remind you of a conference call, and then automatically dial you in.

At $139, the Jawbone Icon HD + the Nerd isn't cheap, but it's an excellent choice for users that want a Bluetooth headset they can use almost anywhere. It looks sharp and sounds great, and the Nerd opens up connection doors in places where Bluetooth won't fit. But if all you're looking for is a headset for your phone, we have two better choices. If you're the type of user that lives on the phone and needs the best possible call quality, the Plantronics Voyager Pro+ is your best bet. It's much bulkier and less stylish than the HD, but it's even more comfortable and its call quality can't be beat. And if you're looking for a great look and superior A2DP sound quality, as well as an even more advanced app platform, the Jawbone Era remains our Editors' Choice for the best overall Bluetooth headset.

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