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Alpine KCE-400BT Bluetooth Adapter review: Alpine KCE-400BT Bluetooth Adapter

Alpine KCE-400BT Bluetooth Adapter

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
4 min read

The Alpine KCE-400BT is part of Alpine's series of add-on modules that, in this case, adds Bluetooth connectivity to receivers that support Alpine's proprietary Ai-NET high-speed connection cable, extending the flexibility of its line of car stereo receivers.


Alpine KCE-400BT Bluetooth Adapter

The Good

The Alpine KCE-400BT allows users to easily add Bluetooth hands-free calling and audio streaming to a compatible Alpine car stereo. Active Echo Cancellation makes calls clear and reduces background noise. Automatic importing of contacts and support for voice dialing makes it quick and easy to initiate calls.

The Bad

Contact list updates can take several moments, during which no calls can be made. Installation requires more steps and hardwiring than a standalone Bluetooth speakerphone. When paired to units that don't feature a touch screen, calls are limited to numbers previously saved.

The Bottom Line

For users who already own an Alpine car audio receiver, the KCE-400BT offers an easy way to extend the functionality, safety, and usable life of the headunit by adding clear, hands-free calling and wireless audio streaming.

However, the KCE-400BT not only adds hands-free calling technology powered by Parrot--makers of the fantastic Minikit Slim--but it also adds the A2DP and AVRCP audio streaming protocols, effectively giving users a whole extra audio source for their vehicles.

The KCE-400BT consists of a plastic hideaway box with connections for Ai-NET data input, an Ai-NET data cable output for daisy-chaining other Alpine add-on modules, a power connection wire harness, and an external microphone with a gratuitously long cable for mounting near the driver's head.

The KCE-400BT's shell is plastic unlike the metal housing of the TUA-T550HD HD radio receiver tested earlier, which is probably necessitated by the KCE-400BT's internal Bluetooth antenna (the TUA-T550HD used an external antenna).

The unit mounts using included hook and loop adhesive strips and is small enough to fit behind the dash or under a seat. We'd suggest that you test for optimal Bluetooth signal strength before permanently mounting the KCE-400BT.

A person with moderate car stereo installation skills could install the KCE-400BT with simple hand tools in about an hour, depending on the number of body panels that need to be removed to cleanly hide the unit and route the microphone cable.

Once powered up and connected to a compatible Alpine headunit, the KCE-400BT can be found and paired with, using your Bluetooth device.

The primary purpose of the KCE-400BT is to add Bluetooth hands-free calling to compatible Alpine receivers.

Devices are paired using a four-digit PIN. Once paired, the KCE-400BT is able to sync the contact list and the most recently dialed, received, and missed calls. This list is auto updating, so if you make a call outside of the car or add a contact, it will be reflected upon the next pairing.

The periodic updating of call lists is very convenient. However, large updates of multiple numbers can take more than a minute, during which no calls can be made. This is only a minor inconvenience that we were willing to tolerate for increased functionality.

Calls are selected on the connected receiver's screen, where caller ID information is also displayed. On receivers such as the Alpine iDA-X305, the user can only dial numbers that are stored in the memory or can be accessed using their phone's voice-dial functionality, if available. Accessing voice dial is accomplished by holding the Phone button on the receiver's face.

When paired with touch-screen receivers, such as the IVA-W505 or IVA-D106 models, an onscreen keypad can be accessed for dialing new numbers.

The hands-free calling technology is licensed from Parrot and comes with Parrot's Active Echo Cancellation technology, which reduces echo from your car's speakers and limits intrusive background noise.

The KCE-400BT also supports A2DP Bluetooth audio streaming, which shows ups as a source on the receiver when paired with a compatible device. Audio quality is good but carries all of the shortcomings of the protocol, including no displaying of metadata with all but a few devices, no searching of media, and only basic audio controls (play, pause, and forward and backward skip).

Upon connecting our KCE-400BT to the Alpine iDA-X305 receiver, we encountered an error that caused the unit to lock up when pairing, necessitating a power disconnect or reset to free the unit. A quick call to Alpine tech support revealed that the problem lied in the "interrupt" setting on the receiver that needed to be changed to "off" prior to connecting the KCE-400BT. Less than 10 minutes later, we were up and running.

Call quality is good but will ultimately depend on the performance and placement of your vehicle's speakers. Even so, even the most basic vehicle speakers are more than adequate for good call quality.

Callers stated that outgoing audio quality was also superb and the included directional microphone with Active Echo Cancellation did a fine job of reducing road and wind noise. Echoes were also negligible, even with the call volume cranked fairly loud.

In sum
With an MSRP of $180, the KCE-400BT is only marginally more expensive than your average standalone Bluetooth speakerphone. However, it brings with it the advantage of using your vehicle's speakers, never needing recharging or dangling wires, and being all but invisible to potential thieves.

For owners of any of Alpine's receiver's that support the Ai-NET connection necessary to connect the add-on module, we feel that the KCE-400BT extends the functionality and the useful lifetime of the receiver by adding the convenience of hands-free calling and the bonus addition of a new audio source.

Alpine also states that the KCE-400BT's firmware will be easily updatable over the same Bluetooth signal that it uses for pairing with devices, which adds a small degree of future-proofing.


Alpine KCE-400BT Bluetooth Adapter

Score Breakdown

Design 5Features 7Performance 8