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BlueAnt S4 Bluetooth Stereo Speaker review: BlueAnt S4 Bluetooth Stereo Speaker

BlueAnt S4 Bluetooth Stereo Speaker

Antuan Goodwin Reviews Editor / Cars
Antuan Goodwin gained his automotive knowledge the old fashioned way, by turning wrenches in a driveway and picking up speeding tickets. From drivetrain tech and electrification to car audio installs and cabin tech, if it's on wheels, Antuan is knowledgeable.
Expertise Reviewing cars and car technology since 2008 focusing on electrification, driver assistance and infotainment Credentials
  • North American Car, Truck and SUV of the Year (NACTOY) Awards Juror
Antuan Goodwin
5 min read

Powered up and hanging from its perch on your vehicle's visor, the BlueAnt S4 is always listening to you. If that seems a bit too "Big Brother," fret not. The S4 is only listening for a specific voice prompt. Simply say, "BlueAnt, speak to me" and the Bluetooth speakerphone springs to life ready to do your bidding.


BlueAnt S4 Bluetooth Stereo Speaker

The Good

The S4's voice trigger grants users access to most of the speakerphone's functions without physically touching the device. "What can I say?" command practically eliminates the need for an instruction manual. Imported contacts' caller ID info is read aloud when receiving a call. Bing-411, Vlingo, and BlueAnt app integration, as well as A2DP audio streaming, extend the device's functionality.

The Bad

The S4 lacks a built-in voice dialer, so if the paired phone doesn't have its own voice dial system (e.g. Android), calls must be manually initiated. In louder vehicles, the S4 had difficulty understanding our voice commands.

The Bottom Line

The BlueAnt S4 delivers good call quality and, with its voice trigger system, increased vehicle safety. However, it excludes many popular handsets from its true hands-free claim by not including its own voice dialer.

Physically, the BlueAnt S4 doesn't deviate too much from the formula we've come to expect from visor-mounted Bluetooth speakerphones. It measures 4.88 inches long by 2.38 inches wide by 0.62 inch deep; the device's face is split between a gloss-black panel and a mesh grill that covers the loudspeaker, separated by a brushed-metal band that bears the BlueAnt logo. Just beneath the gloss black front edge are three hidden color LED lights: blue for connection to Bluetooth, green for listening mode, and red for battery state.

Where many devices use snap- or slide-on visor clips, the S4 has a pair of strong magnets that connect to the device's pair of interchangeable visor clips: one for narrow sun-visors and another designed to grab slightly thicker visors.

Along the S4's left side is the three-position power switch and, beneath a rubber flap, a Micro-USB port for charging and firmware updates. The power switch is the S4's only physical control. The rest of the user interactions are either voice controlled or accessed by swiping or tapping the device's touch-sensitive front edge. For example, swiping from left to right increases the volume, and right to left decreases. Tapping the device brings up the voice command prompt, or answers or rejects a call.

Along with the S4 speakerphone and its visor clips, users will find a 12-volt USB car charger, a 12-inch Micro-USB cable, and an extremely thorough user guide--a rarity with gadgets these days.

The BlueAnt's most interesting feature is its hands-free trigger mode. While in trigger mode, a green LED is illuminated to indicate that the BlueAnt is listening for its activation phrase, "BlueAnt, speak to me." When the device hears this phrase spoken, it goes into listen mode and becomes responsive to its full list of voice commands. Users can ask the BlueAnt for information about its pairing state, update the phone book from a paired handset, check battery status, or query the S4 for a list of available commands.

Of course, users can also make hands-free phone calls. Incoming calls can be answered or rejected by saying "answer" or "reject." If, during pairing, you allowed the BlueAnt to upload your phone's address book, incoming callers will be announced by name.

Interestingly, the BlueAnt S4 doesn't seem to have its own internal voice dialing system, instead deferring calling duties to your paired phone's voice dialing system, if available. Outgoing calls are initiated by saying, "BlueAnt, speak to me" then "Phone commands" to access your paired phone's voice command system. If your phone doesn't allow access to external voice commands, as is the case with Android phones, then you're out of luck and will need to initiate your calls from your handset. This is more of a limitation of the paired phone than that of the BlueAnt S4 itself, but other systems like Ford Sync or Kia's OEM hands-free system get around this hurdle by running their own voice dialing software.

In addition to hands-free calling, the BlueAnt S4 also supports A2DP audio streaming for listening to music or receiving turn-by-turn directions from a running GPS application. The unit also supports multipoint pairing for connecting to two devices simultaneously. When connected to two phones, the S4 can receive calls from either handset, but can only stream A2DP audio from the primary phone.

We conducted our testing of the S4 with the Motorola Droid.

The S4 features two power modes selected by moving the power switch. The first position is a power saver mode. In this mode, the S4 will only remain in trigger mode for 2 minutes at a time, after which it will stop listening for the "BlueAnt, speak to me" command. When this happens, the green listen light will go out and users will need to tap the device's touch-sensitive edge to wake it back up.

The second position is an always-on mode that keeps the BlueAnt alert and listening until it is either unpaired or powered off. This is the true hands-free mode that requires no physical interaction from the users, save for swiping to adjust the volume or tapping to manually end a call.

When attempting to update the phonebook, the S4 would get stuck in a loop, repeating "Updating contacts" over and over for minutes at a time or until we got annoyed and hit the cancel button. We're not sure if this was an issue with our Droid or a bug with the S4, but it was quite annoying. This seemed to only be an issue with updating, not the initial sync. Disconnecting and re-pairing the phone seemed to fix this issue.

External services
The BlueAnt S4 comes preloaded with shortcuts to Microsoft's Bing-411 services that are completely accessible via voice command. Speaking the trigger command followed by "Favorites" then one of the Bing commands--such as Movies, Traffic, or News--dials into Bing's servers to receive spoken information about a variety of subjects.

Users can ask Bing about movie times, stock quotes, news updates, weather and forecasts, sports scores, etc. There is also the option to get spoken turn-by-turn directions and the latest traffic conditions. Verbally entering your information can be a bit time consuming and the call counts against your cell phone's available airtime, but it's a good option to have especially for users who don't have smartphones and who just want to occasionally look up a movie time. The turn-by-turn directions system requires a constant connection, so if your call gets dropped while you're en route, you'll need to redial and restart navigation from your current location, and because the system isn't GPS-based--like OnStar or Ford Sync turn-by-turn systems--finding your current location can be tricky at times.

BlueAnt also offers a BlueAnt app for Android, available in the Android Market. This app offers help with pairing an Android Phone with the S4, lists the available voice commands, and can read received text messages aloud through the S4's speaker.

The S4 is also compatible with the Vlingo SafeReader app for BlackBerry and Android phones, but we were unable to locate the app in the Android marketplace for testing. An iPhone version of the Vlingo app is said to be coming soon.

In sum
The BlueAnt S4's lack of its own internal voice dialer is a bit of a black mark on BlueAnt's claim of the device being the first "true" hands-free system, putting the speakerphone at the mercy of the capabilities of phone with which it is paired. Users of, for example, Android phones will find this to be quite an annoyance.

However, for users of the phones that feature their own built-in voice dialing system and users who don't initiate many calls while behind the wheel but want to be able to safely answer incoming calls, the addition of the BlueAnt S4's voice-triggered hands-free system has the potential to elevate vehicle safety by allowing drivers to keep their hands on the steering wheel at all times. Additionally, for users who don't have smartphones, the S4's tight integration with Microsoft Bing voice service also adds a degree of utility to the package.


BlueAnt S4 Bluetooth Stereo Speaker

Score Breakdown

Design 9Features 8Performance 7