An adapter is required to add Bluetooth transmission capability to a device that does not have one. There are several on the market and among our pages we have already talked about them abundantly over and over again through reviews that went to look at them a little more closely.
In this article we will look at three different Avantree models – CK121, CK210 and CK310 – that the company has offered us on trial and show you the advantages and disadvantages of one and the other and where each brings out the best in itself.
Avantree CK121
Small and compact, it is made of polycarbonate and is the one that comes closest to many others of its kind in terms of shape and type of operation. Among the three, it is also the one that best suits the most common situations: in fact, the package includes a small 3.5 mm jack-jack plug that allows easy use with the car radio, eliminating cables and tangles.
At the same time, however, this plug can be replaced by a 3.5 mm jack-jack cable that allows you to connect the receiver even to less easy-to-reach sockets, such as the rear one of a stereo system, a computer or any other audio device. equipped with this entrance.
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Avantree CK210
It is similar to CK121 in size and shape, but it is built with a plastic that is apparently more robust and more pleasant to touch due to the satin finish that covers the entire outer shell. Here, however, we are faced with a device designed specifically for use in the car (although it can also be connected to other 3.5mm jack ports).
In fact, it incorporates the jack plug that is extracted with the simple press of a button with a system that replicates what we find in the ignition keys for cars. Just press the button and the jack plug will immediately snap out to allow connection.
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Avantree CK310
Completely different from the previous ones, it has a circular shape and a touchscreen display on which the frequency and operating keys are displayed. It is designed exclusively for use in the car but here the connection to the car radio does not take place physically through a cable but by hooking up wirelessly to an empty radio station. In other words, it is sufficient to manually search for a free frequency on the car radio, then set the same in the receiver by pressing the “+” and “-” keys: in a flash the audio system will be equipped with Bluetooth technology.
Since it does not physically attach itself to the audio device, it is equipped with a velcro system on the bottom so that it can be attached to the dashboard or in the most congenial position for its use. In the package there are two Velcro stickers to allow you to move the receiver from one car to another without having to buy a second one.
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What they have in common
All three are equipped with buttons (touch in the CK310 model) that allow the control of music playback without having to interact with the paired smartphone. That is, you can start or stop playback of a playlist, adjust the volume or skip to the next song and go back to the previous one by pressing the relevant button integrated in the receiver.
In addition, each has a microphone that enables its use even during a phone call. In this way, in addition to music playback, you can speak hands-free with your interlocutor using the microphone integrated in the receiver and the audio system to which the latter is connected.
All three then incorporate a battery for power supply, a battery that is recharged by connecting the microUSB cable included in the package to the relative port.
How are they different
Between the first (CK121) and the second (CK210) the main difference lies in the versatility of use. As mentioned, the CK121 model is equipped with a push and jack cable that facilitate its connection both in the car radio and with a stereo, while the CK210 model is slightly better built, has more comfortable buttons to use and is mainly designed to be connected to the car radio. Having movable but non-removable parts it is also easier to slip into your pocket to always have it with you without running the risk of losing or breaking the adapter for direct connection.
The third (CK310) is completely different from the others because it does not physically connect to the 3.5mm audio jack port but uses unused radio frequencies. Therefore it is the only possible option for all those older generation car radios that do not offer the AUX connection. This important difference also modifies the final quality: the cable connection ensures a continuous signal transmission while with CK310 everything depends on the frequency to which the receiver is connected.
Between one city and another, a free frequency can suddenly be occupied by a radio station and at that point the wireless connection of the receiver with the car radio fails, forcing the user to stop the vehicle safely, search for a new free frequency, pair the two devices and restart. Therefore we recommend the purchase of the CK310 only if forced by the absence of the AUX connection in the car radio: in those where there is the 3.5mm audio jack socket it is advisable to purchase one of the other two models.
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How are they doing
The transmission quality is the same for both. The controls respond well and the audio quality of the microphone is very good. The system is able to isolate ambient noise sufficiently well and guarantee a good quality of communication with the interlocutor, even when the car is in motion and the windows are down.
We also report that all three are able to work while the battery is charging, so it is possible to eliminate the annoyance of suddenly seeing the Bluetooth connection cut off while listening to a playlist or a phone call simply by leaving the microUSB cable connected to the receiver. (obviously by connecting the other end to a power bank or to a power supply, whether it is the one plugged into the home socket if you use it with the stereo or the one plugged into the car's cigarette lighter socket).
What didn't we like? The power button. Different for each and sometimes impractical. In CK121, for example, it is necessary to hold down the Play / Pause button for several seconds both to switch it on and to switch it off (confirmation of switching off is given by the illumination of the LED indicator with a continuous red light); in CK310, on the other hand, simply press the special On / Off button to switch the receiver on or off (therefore, watch out for accidental presses); that of CK210 is perhaps the best because it deals with a switch rather than a button, so it will be sufficient to move the selector to the On or Off position respectively to turn the receiver on or off.
Retail price
Whichever receiver is right for you, the price is more or less the same for everyone: CK210 and CK310 cost 24.99 euros, while CK121 (which, we remind you, is more versatile than CK210 but constructively satisfies less) costs 19.99 euros. All three are sold by Avantree but shipped by Amazon, thus allowing you to benefit from all the advantages related to any assistance and return.
