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GoGroove FlexSmart X3 review: FM transmitter improves, but not by much

FM transmitter-based car kits have been around for ages -- is there still room for this tech to improve?

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

FM transmission is pretty old tech. Feed the transmitter an audio source and set it to broadcast on an open FM frequency. Then tune into that frequency on a nearby radio and enjoy your wireless music.


GoGroove FlexSmart X3


The Good

The <b>GoGroove FlexSmart X3</b> features improved automatic channel scanning when compared to the old X2 model. Fit and finish have been improved. 3.5mm input and output connections give users more options.

The Bad

High-pitched alternator whine beneath the audio was a minor annoyance. FM automatic scanning was less accurate than other GoGroove models we've tested.

The Bottom Line

The GoGroove FlexSmart X3 makes a strong showing, but is overshadowed by its sibling the GoGrove SmartMini.

It's simple, old radio tech, but the FCC imposes limits on how strong these transmitters can broadcast their wireless signals. That doesn't leave much room for improvement. Perhaps that's why, despite a fresh coat of paint and tweaks in tuning sensitivity, the new GoGroove FlexSmart X3 doesn't feel head-and-shoulders better than the FlexSmart X2 that I reviewed over two years ago.

But just a few months ago, I was praising another GoGroove FM transmitter for exceeding my expectations for the category, so perhaps the X3 will wow me yet.

The new Flexsmart X3 model has a new, white design that looks sleeker and more compact than the previous X2 model. Break out your tape measure, though, and you'll see that the overall dimensions haven't really changed much. The glossy white-and-gray plastic reminds me of a classic iDevice and should stick out quite a bit in pretty much any vehicle interior. A darker option would be nice.

It doesn't just look slicker; the X3 also streamlines its interface by integrating the call answer and end buttons into the black plastic that shields the red LCD tuning display. Gone also is the control knob that the old model used to manually tune radio stations. In its place, you'll find a circle of buttons and a larger emphasis on the automatic scanning.

Largely, however, this is the same Flexsmart form factor as before. The body still sits atop a long, flexible stalk that joins it with a 12V power plug that integrates a small power button. Sure, the stalk now has a metallic finish and everything is all shiny and new, but the more things change, the more they stay the same.

Even the physical connections on the device are the same. At the base of the main unit, you'll find a powered USB port for charging a paired phone (now outputting 1A at 5V like the recently tested GoGroove SmartMini BT) using the included USB-to-Micro-USB cable. There, you'll also find a pair of 3.5mm analog auxiliary connections for input and output.

What the GoGroove FlexSmart X3 does is simple: it gets audio from your phone to play through your car's stereo system. The device gives you multiple means to this end.

It can receive audio data from your phone's Bluetooth connection and rebroadcast it wirelessly to your car's stereo via FM transmission. Alternatively, you can go from a wired connection to FM transmission by plugging into your phone's headphone jack or go from Bluetooth to a car stereo that features an analog input using the included patch cable.

If you're feeling needlessly complicated, you can even go from your phone's headphone jack to the X3's aux-input and then from the X3's aux-output to your car stereo's 3.5mm port with two cables. I'm not sure why you'd want to do that, but you have the option.

Of course, the optimal connection method uses your phone's Bluetooth connection to send calls and music. In this way, you gain both the ability to take control of your device to play, pause, and skip via the AVRCP controls on the X3's face and to make hands-free calls via the device's pinhole microphone.

The hands-free calling system is a simple one: there's no address book sync or built-in voice command system. However, the system will pass your spoken commands through to your phone's voice command system after holding the blue call button for a few seconds -- not a bad feature to have if you're already a fan of iOS' Siri or Google Voice Search.

Interestingly, I had a slightly harder time finding a clear station with the FlexSmart X3 in my San Francisco and Oakland testing areas than I did with the GoGroove SmartMini, which I assumed to be largely identical internally. I've got a few guesses as to why.

Firstly, the way that automatic scanning for a clear FM station is initiated by pressing and holding the "play" button on the X3's face. However, touching the X3 caused my hand to act as a sort of external antenna, artificially altering the transmitter's performance and creating false positives for clear stations. It would show all clear, until I removed my hand from the device and then the signal would fade again. It wasn't the end of the world, I just had to make sure not to let my fingers linger when channel scanning to guarantee the best results.

Automatic tuning is made all the more difficult by the fact that, like the SmartMini, the FlexSmart X3 is able to tune even as well as odd decimal frequencies (88.4, 88.5, 88.6), whereas most American car stereos that I've encountered can only tune to odd increments (88.5, 88.7, 88.9). This means that about half of the stations the Smartmini returned were frequencies like 104.4FM that my car couldn't match. Sometimes tapping a manual tuning button one tick up or down one decimal place would help, but usually I just had to try autotuning again.

Finding a clear station may take a bit of care and work, but the FlexSmart X3 is definitely capable and up to the task -- which is saying a lot. I was able to find serviceably clear signals even amid the crowded air waves of downtown San Francisco. When the signal got hairy, sometimes just a tweak of the FlexSmart's neck was enough to restore clarity. Other times, a new station was just a few taps away. Once I got outside of the metro areas and onto the open road, I was able to quickly lock in on and hold clean channels with little effort at all.

Audio quality was merely OK, but that's par for the course when you're talking about FM transmission. Anyone who claims "crystal clear" clarity from an FM transmitter is either exaggerating or has a tin ear. On our test car, a 2006 Chevrolet Aveo, I noticed that X3's FM transmitted audio was characterized by a high-pitched alternator whine that rose and fell with the engine's revs. This minor annoyance wasn't evident when testing GoGroove's SmartMini in the same vehicle or with other radio station on the FM band.

In sum
The GoGroove FlexSmart X3 performed well, but at the end of my testing, I recommend GoGroove's own SmartMini BT for those drivers for whom FM transmission is the only option for car audio. Both devices are about the same price; both give the user a variety of ways to connect their high-tech phone and even the most basic of car stereos; and both are operated with similar levels ease.

However, the SmartMini BT was just a hair more consistent when scanning for and hanging onto those quiet places among the crowded airwaves than the long-necked X3. Additionally, the high-pitched alternator whine that annoyed me with the newer FlexSmart X3 wasn't present with the more compact SmartMini device. My guess that the darker SmartMini presents a lower-profile target to would-be thieves is just the icing on the cake.


GoGroove FlexSmart X3


Score Breakdown

Design 5Features 7Performance 5