The SuperTooth CRYSTAL has a sleek pill-shaped design with an anodized-aluminum body and a magnetic clip that’s easy to install on your sun visor. Like many affordable Bluetooth hands-free car kits, it only has one omnidirectional microphone and one speaker. However, the call quality belies its name, as the audio is anything but crystal clear. In addition, its missing hands-free features and five buttons mean your eyes are pulled from the road more than with the best Bluetooth hands-free car kits.
We tested the CRYSTAL alongside three other visor-style Bluetooth car kits, and it had the worst call quality of the bunch. It earned the highest marks when the car was parked and idling, but as we drove through cities and on freeways, the ambient noise grew louder, and the device’s lack of effective noise cancellation became evident. Still, its call quality was much better than that of the AUX-in Bluetooth car kits we tested and far better than the Bluetooth FM transmitters. As one of the most affordable in-car speakerphones, it’s a good option for drivers who want to make hands-free calls but don’t want to pay $80 to $100 to do so.
While the microphone uses DSP to reduce noise, it doesn’t have HD Voice, which means it uses the standard narrowband frequency range of 150Hz to 3.4kHz. This narrow frequency range makes voices sound tinny and thin. In comparison, the best Bluetooth car kits feature HD Voice, which uses a wideband frequency range of 50Hz to 7kHz to produce a more realistic and detailed sound. On top of that, the volume output isn't very loud – it measured the lowest maximum volume in our tests.
The CRYSTAL attaches to the sun visor with a magnet, which makes it really easy to remove for recharging. As with most visor-style Bluetooth car kits, the clip is very tight. If your sun visor is even remotely thick, it’s difficult to slip on an off. With the magnet, you only have to slip it on once. However, for reasons unbeknownst to us, the backside of the CRYSTAL was dabbed with some sort of glue that was sticky and didn’t come off. It’s almost as if the company wasn’t confident in the magnet’s ability to hold the device to the clip.
The SuperTooth CRYSTAL’s best feature is its 20-hour battery life. It also turns on automatically when it senses the car door open and close – you just have to get in your car, and it automatically powers up and pairs to your phone. When you leave your car, it automatically turns off. However, the battery charging port is inconveniently placed on the back of the device, which makes it impossible to charge while it's mounted to your sun visor.
This hands-free Bluetooth kit is missing many features. While it has the Hands-Free Bluetooth Profile, which allows you to use voice commands to answer and end calls, it lacks a text-to-speech and speech-to-text feature. It also doesn’t have a vocalized caller ID feature. The CRYSTAL’s A2DP Bluetooth Profile allows you to stream music and GPS directions, but you can't remotely control your phone or mute a call from the device.
The SuperTooth CRYSTAL’s call quality is what you'd expect from a Bluetooth car kit in its price range – standard narrowband audio with inconsistent and ineffective noise reduction. It has one of the best batteries, and the voice commands are useful, but the lack of additional Bluetooth profiles means that you have to take your eyes off the road to use many of its features.