Review: Kii Three with Kii Three BXT System

The Belgian Bruno Putzeys laid the foundation for class D amplifiers. Review: Kii Three with Kii Three BXT System built to perform.
5/5 - (3 votes)

A lesson in basic acoustics teaches us that large loudspeakers must have much more precise timing and detailing of the bass and mids than compact speakers. This is due to the size of the ‘baffle’ or the front of the speaker. The smaller the baffle, the more low tones are radiated around the speaker instead of towards the listener. In short, but that’s the bottom line. And Bruno Putzeys has come up with something for that with Kii Audio.

Bruno Putzeys

The Belgian Bruno Putzeys laid the foundation for class D amplifiers. He designed the first UcD class D amplifier module for Philips. A few years later he developed the Ncore amplifier module for the Dutch company Hypex. This module is widely regarded as the first Class D amplifier to rival pure Class A amplifiers. Bruno Puzeys caused a furore in the audio world with no fewer than nine patents in the field of digital audio and power conversion. For example, he developed high-quality D/A and A/D converters for Grimm Audio and Mola Mola. Together with Peter Lyngdorf and Lars Risbo, he was one of the founders of the Danish company Purifi Audio, which mainly focuses on class D amplifier modules and revolutionary loudspeaker drivers. For the record, the class D amps that Bruno Putzeys designs are purely analog amps, not digital ones!

Kii Audio

Since the founding in 2014 of Germany-based Kii Audio and its partnership in Purifi, Bruno Putzeys has focused on building compact, active speaker systems. With the intention of making them as revolutionary as its amplifier modules. The Kii Audio range consists of the Kii Three System and the Kii Three BXT System.

Kii Three System

What at first glance seems like a nice set of speakers, is actually a powerful audiophile music system. Stylishly designed and small enough to fit into any modern living space. Without the need for a tangle of cables and a pile of audio equipment. The Kii Three System is a compact DSP Controlled Full Range system. An active speaker system to which analog and digital sources can be connected.

Active Wave Focusing Filter

Conventional loudspeakers radiate in all directions right up to the midrange. As a result, the sound will, for example, reflect against the back wall and return to the listener with incorrect timing. This causes the listening room to boom enormously. The Active Wave Focussing filter of the Kii Three System, on the other hand, creates a directive and controlled radiation behavior. Those reflections are neutralized by the Kii THREE’s total of six side-mounted and rear-mounted drivers, which are driven in antiphase and with adjusted timing. In this way, the music signal is correctly directed towards the listener. Also called a ‘cardioid’ (kidney-shaped) radiation pattern in technical terms, this is the great asset of the Kii Three System.

Kii Control

The Kii Control is much more than a remote control. This controller is an ultra-compact control unit and USB interface. The Kii Control makes it possible to connect multiple sources, both digital and analog, and to set the system sound so that the reproduction is correct in every room. Thanks to the possibility to create six sound presets, everyone can set their own preferences.

Kii Three BXT Expansion Module

The Kii Three BXT expansion module transforms a Kii Three into a high-quality floorstanding speaker, BXT stands for Bass Extension. However, it is by no means a subwoofer. By adding this module, the music system is expanded with no fewer than sixteen extra drivers and amplifiers. The custom Class D amplification delivers 250 Watts per speaker unit and consists of six speaker groups with a total of 1,500 Watts. The BXT expansion module has the same cardioid radiation behavior as the Kii Three, although the supplementary drivers are mounted differently. What is also unique is that the Kii Three BXT System combines vertical and horizontal beam steering. Below 250 Hz, the system is a line source, which ensures that ceiling and floor reflections are eliminated. Together with the cardioid radiation, this results in an even tighter bass reproduction with an unprecedented speed. The Kii Three detects when a BXT expansion module is connected and automatically makes the necessary adjustments to the settings of the software.

Color combinations

Both the Kii Three System and the Kii Three BXT System are available in the standard colors High Gloss White and Graphite Satin Metallic. Other colors are also optionally available, as is the combination of different colours.


We listened to the Kii Three System with BXT module at Hifi Corner in Antwerp. We can be brief about the set-up. We didn’t need more than a Bluesound Node music streamer to make music. We didn’t have to worry about the setup of the Kii Three. The Active Wave Focussing Filter keeps the listening room under control so that the speakers hardly need to be shuffled.


From the first notes it becomes clear that the Kii Three, without the BXT expansion module, has a decent portion of power. It’s impressive how easily the Kii Three makes music. Immaculate and sublimely detailed with a dynamic that blows our minds. The music hits us exactly where it should, the result of perfect timing. When we walk through the listening room, we hear how little it matters. No trace of disturbing reflections anywhere. Behind the Kii Three speakers it is, so to speak, very quiet. The drivers on the back of the speaker work in conjunction with the drivers on the side.

heavy nuts

We don’t want to make it easy for the Kii Three and the BXT System. That is why we sift through the playlists for pieces of music that can put a set to the test. Drums stop, no good by the Vital Techtones is one such song. Just like Glem Ikkje by Kari Bremnes and Defeated Clown by Hildur Guonadottir. To let the violence of the fantastic bass sink in for a while, we switch to Chopinesque by Jon Batiste. Batiste’s piano is almost physically present. Just like Dominique Fils-Aimé who drags us into the music with the super dynamic Birds. Bitter Ballad by Youn Sun Nah is an absolute gem. We have rarely experienced Sun Nah’s crystal-clear, frail voice, the subtle percussion and the deep bass. Tough nuts to crack, but the Kii Three has no problem with it.


And then it’s time for the BXT module, which can be easily switched on or off via the Kii Control. We repeat the songs we listened to earlier and find that the addition of the BXT module results in an even deeper continuous layer and a higher sound pressure in the very lowest frequencies. We don’t just hear it, we even feel it. Logical, when you know that the BXT System adds no less than eight extra woofers and eight 250 Watt amplifiers with built-in DACs and DSP per module. The system will never be short of breath, no matter how far we turn the volume knob. The louder we play, the more subtle nuances and details reveal themselves. The only limitation is the capacity of our ears. The longer we listen, the more we get carried away by the music. Without any trace of listening fatigue. This just makes us happy.


The Kii Three with BXT module is definitely not a music system to provide some background music. This system is built to perform, but at a very high level. And that in both small and large spaces. This is mainly due to the Active Wave Focussing Filter that keeps the listening room under control. A good alternative to room correction. The Kii Three System as a stand alone on the beautiful Kii HiFi Stands does its job perfectly. But with the addition of the Kii BXT module, the gates of heaven open. The fact that the its BXT System also looks particularly attractive is an additional asset. We are curious to see what Bruno Putzeys will be up to for Kii.

Writer: Eduard Hendrix


  • Kii Three System € 14,883
  • Kii Three BXT System €32,065
  • Kii Stands €1,016

Prices include Kii Control and in the standard color.