The Astell & Kern Kann Ultra is High-End Digital Audio Player retailing at 1899€ in the EU.

Unboxing, Build & I/o:

The Kann comes in a nice small box along with a USB cable for charging, data transfer and USB Dac functions and a set of screen protectors
that's it, i feel that considering the asking price A&K could have included a protective case to protect the unit, instead there is
an option to purchase a leather case from them but a whopping price of 149€, so yeah the unboxing experience is altogether a bit
disappointing.....

....but the build quality of the Kann makes up for it. This a very robust device & has a decent heft to it, no doubt that this
is high-end portable digital player. It is heavy though, weighing at 390 grams and with size of 82.4 x 141.1 x 24.4 mm it is barely
pocketable, so i guess that something like a Fiio JM21 will be a much more convenient choice on the go as it is very small & lightweight
but with some concessions regarding sound quality. Back to build quality as already mentioned before it is superb, the chassis is
made out of medal, so are the buttons and volume wheel, the screen is excellent too it is 5.5" touch screen with a resolution
of 1080 x 1920 pixels more than enough for such a device. In terms of i/o there are dedicated headphone & line outputs both single ended
and balanced options on top of the unit on the other end you will find an micro sd-card slot and Usb-c connector for charging, data
transfer & DAC duties. The design as a whole is fantastic in my opinion there are just three buttons on the left side for skipping tracks
and play/pause, the on/off button on top and the great looking and feeling volume rotary knob.

Specs & Functionality:

The Heart of the Kann Ultra consists a powerful Octa-Core Processor which delivers fast and smooth handling when browsing through
the music library, the unit is running on a closed down android system meaning that it is focused on audio playback, there are
only a few streaming apps that can be downloaded such as Qobuz, Tidal and Roon Arc, you cannot play games or watch videos on youtube which
can be a pro for some and a con for others. One of the highlights of the Kann Ultra is the Crimson UI, it's a breeze to use when
browsing to the music library and the album cover arts look absolute ly amazing. Now for audio reproduction the Kann is equipped with
Dual Flagship ES9039MPRO ESS Dacs in fully differential design supporting bitrates up to 32bit/768kHz and Native DSD512 playback
On the amplification side the Kann uses the inhouse TERATON ALPHA technology capable of delivering a maximum of 16 Vrms of output power
on the 4.4 balanced output, so on paper plenty of power for almost any IEM and full-size headphone out there. There are 4 gain
settings available so there should not be any issues in finding a good match from sensitive IEMS to demanding headphones.
The 8400 mAH battery should ensure up to 11hrs of playback in theory, i cannot confirm these numbers i mostly got about 8 hours of
usage with Iems at Medium Gain and maybe about 1 hour less when using full-size headphones at Super high gain, but i guess this
is still ok with such a powerful device.

additional features:
There are some interesting features that can be enabled through the drop down menu like EQ, Crossfeed, Dac Filters and Digital Remastering
functions, so a lot to play around with and to alter the sound to your preferences.

Sound Performance & Pairing:

The Astell & Kern Kann Ultra delivers a mostly neutral sound presentation with an insane amount of detail and a big soundstage.
All of my IEM's were driven very beautifully with authority and to their full potential. Most full-size headphones work very
well too with some exceptions. The first one that didn't work well with KANN Ultra was the Hifiman HE-6 SE V2 but it is no
surprise to me as this one is notoriously hard to drive even a lot of desktop amps fail to drive it properly. The second one though
was a bit surprising, pairing it with the DCA Noire X revealed that it seemed to have issues driving low impedance planar
headphones, at medium volumes they sounded very good but when cranking up the volume to my regular listening levels there was
some noticeable distortion in the low end, so it seems that the amplifier stage doesn't produce enough current for these.
On the other side headphones like the Hifiman HE-1000 V3 sounded amazing with this DAP, very detailed, wide soundstage and
great low end performance almost to the level of my a desktop Dac/Amp the Luxsin X9.
Out of curiosity i also used the Dac output of the Kann Ultra with two of my desktop amplifier the Aune S17 Pro and the Feliks Audio
Echo Mk2 Tube Amplifier and what i can say is that the DAC performance was excellent, it performed slightly better than the Dac
output of the Eversolo DMPA-6 MA Edition and was at least on par with Dac output of the Luxsin X9.

Comparisons:

To make this one very short, i just got in the Fiio M17 DAP and i will do a full comparison on that one when i have fully
tested it, but one thing is already certain the Fiio is a lot more powerful than the Kann Ultra but it is also bulkier so
let's see. Against the older DAP's i have listened to in the past there is simply no competition to the Kann Ultra's performance.

Final Word:

The Astell & Kern Kann Ultra is a great DAP for sure but is it worth 1900€ that's the big question here.
In terms of usability and the exquisite build quality it is hard to fault. The sound quality is top notch with IEMS and
with a wide range of headphones, but you have to be careful though with low impedance planar headphones and very power
hungry headphones. I think the inclusion of a nice protective case would have made it easier to give a recommendation,
so for now i leave there....