X-Mini™ KAI Bluetooth Capsule Speaker [REVIEW]

Developed by X-Mini™ in Singapore, the pocket sized X-Mini™ KAI Bluetooth Capsule Speaker is the company’s first wireless speaker in its portable capsule speakers lineup. Equipped with Bluetooth wireless technology, a built-in mic and a rechargeable battery, this 2.5W portable speaker produces an unbelievably loud sound, ideal for any kind of music on-the-go. Full review after the break.


  • 40mm Drivers
  • Bluetooth-equipped
  • Built-in microphone
  • Buddy Jack
  • Bluetooth Dongle
  • Rechargeable battery


  • Dimensions: 50.0mm X 62.0mm (closed resonator)
  • Weight: 95.2g
  • Speaker: Magnetically Shielded 40mm (4?)
  • Loudspeaker Output: 2.5W
  • Frequency Response: 100 Hz – 18 kHz
  • Battery Capacity: 550mAh
  • Bluetooth Compliant: v2.1 + EDR
  • Bluetooth Profile support: A2DP Stereo
  • Bluetooth Playback time: Up to 4 hours
  • Talk Time:Up to 8 hours



The X-Mini™ KAI comes packaged in a decent box. Along with the KAI Capsule Speaker, you get a USB charging cable which also duals as 3.5 mm cable for connection to non-Bluetooth devices, instructions manual and a soft carrying pouch.

The X-Mini™ KAI Capsule Speaker features a nice and compact design. With a 40mm magnetically-shielded speaker driver, this matte black speaker is small enough to hold in the palm of your hand. The speaker’s versatile design allows it to close down with a twist for easy storage and added portability (see photos below).

The overall build quality is also decent enough for a portable, lightweight speaker. The speaker’s top highlights an etched company logo, underneath which lies the silver cone of 40mm driver. All the other ports and switches are located around the base of the speaker.

Lifting up the capsule speaker shows a jog dial which lets you switch tracks, play / pause music etc. There is also a mute switch beside it. An on/off switch lets you select between Bluetooth wireless mode or wired audio through 3.5mm jack. Further to the right is a mini-USB port for charging the device. The same port also outputs audio via the supplied USB cable which has a 3.5mm jack for simultaneous charge and play. An attached cable with 3.5mm jack at the base allows for an easy wired-audio connection.

There is another 3.5mm audio socket around the base which is actually what makes the X-Mini™ KAI a real champion. This particular audio socket which is also called the “Buddy Jack”, allows you to connect another X-Mini™ Capsule Speaker which may be further connected to another one and so on, letting you daisy chain all your X-Mini™ speakers for an immense boost in sound. Best of all, the same port can be used to wirelessly connect to your home sound system, essentially turning the X-Mini™ KAI into a Bluetooth dongle. Awesome eh!

Bluetooth pairing is as simple as it gets. Simply turn on the speaker by flipping the switch towards the bluetooth, search for Bluetooth devices on your iPhone etc. and tap ‘X-mini KAI’ to connect. A small blue LED strip lights up in Bluetooth mode which also acts as a battery level indicator.

Lastly and most importantly, the sound produced by X-Mini™ KAI is by no means ‘mini’. The very first time when I paired it with my iPhone and tapped the Play button, I was like “holly sh….is this sound really coming out of this?” I bet no one can expect how loud the KAI will sound just by looking at its size. What’s even more surprising is the reasonably punchy bass produced by the tiny capsule. Of course you won’t be hearing any thundering base but the overall balanced sound produced by KAI is pretty amazing for such a small speaker. A full charge allowed just over 4 hours of non-stop playback over Bluetooth during my testing. Not to forget the built-in microphone which may prove handy for making a hands-free or a conference call.


Without exaggerating, let me tell you that the sound produced by X-Mini™ KAI is not only crisp but also loud enough to blow away most casual listeners. And with the ability to act as a Bluetooth dongle for just about any wired sound system, I would strongly recommend it to anyone looking for a loud, convenient and easy to transport audio option.