The Luxsin X9 is an extremely versatile Headphone Amplifier with integrated DAC implementation, all in a single box
with an insane amount features and sound customizing options for your headphone and IEM collection. It sells
in the EU at 1099€ so it's certainly not a cheap unit but it's got a lot going for it. As for the brand Luxsin
they are sub brand of the Zidoo group whom also have Eversolo und their "umbrella" which is well known for
producing excellent streamers & Dacs so my guess is some of their knowhow has been incorporated into this product.

Unboxing & accessories:

The unboxing experience is quite satisfying, the unit itself comes protected in a nice bag, the X9 feels very premium,
quite heavy and solid when holding in hands, the CNC-machined aluminum chassis is well crafted, the hires touch display
at the center and the illuminated volume knob add the finishing touch to the package. As for the accessories you get
two different types of USB cables, a 3.5 to 6.35 adapter, a power cord and a generic plastic remote.

Under the Hood:

The DAC section is based on a high performance AK4499EX/AK4191EQ flagship chipset from AKM paired with an XMOS316 for USB decoding,
the amp section is a fully balanced design equipped with TPA6120A2 stereo headphone amplifier IC from Texas Instruments
and OPA1612 dual-channel operational amplifier capable of putting out 4000mW at 32 Ohms from the balanced headphone sockets
which should be enough to drive 95% of the headphones out there.

Design, I/O & hardware features:

Looking again at the unit itself one can immediately notice that the X9 has been designed primarily for desktop use, the
front panel with it's display is slightly inclined towards the end user to enhance visuals and ergonomic touch control.
The gorgeous 4 inch touchscreen is very sharp, colorful and easy to read, it will display all relevant information,
like bitrate, volume, output, vu-meters and spectrum analysers depending on what option has been selected by the user.
There are various options on how to control the X9, over the touch display or the stock remote control can be used,
it can be app controlled via an IOS or Android phone, and even via a desktop pc or laptop via a browser of your choice.
Still on the front left there 3 headphone sockets, with XLR, 6.35mm and 4.4 pentaconn all major connections are supported.
On the right a big R2R volume knob enables left-right channel balance adjustments with exceptional accuracy & precision.
Lastly next to the volume knob there is an on/standby/mute button. To completely turn off the unit you have to reach for the
switch at the back of the unit which is very crowded in terms of in- and output options. So from left to right you will find
the switch to completely shutdown the X9, a power plug, in- and out- triggers, USB for firmware update, a USB-C & a
USB-B Input, a HDMI ARC input, a Coax, a Optical and even one analogue RCA input, on the Output side you will find SUB Outs and
both RCA and XLR outputs. So basically the X9 can also be used as a quality preamp in a speaker system which i will not
mention in this review as i will be focusing solely on headphone gear.

Usability & software features:

The Luxsin X9 is not a simple DAC & Headphone AMP, it has a lot of interesting und unique features not previously seen
in any other device like this. Firstly the X9 can detect the impedance of any headphone automatically when
using either the 4.4 balanced or 6.35 single ended output socket so what it does it will adjust the most suitable output
gain setting to the connected IEM or Headphone without any impact on sound quality. The second nice feature is crossfeed.
What this does in simple words is it is trying to emulate a speaker like listing experience with any headphones you plug
into the X9, and it is very well implemented here, you can choose between 3 different crossfeed levels and if it is not
enough users can also adjust soundstage depth and width. The last and maybe most important feature is the HP-EQ System
which lets you download and install custom Eq profiles for your headphones. The database contains profiles for over
2000 headphones and IEM's and still growing, and you can go even further in modifying the downloaded to create your
own versions or create you own EQ from scratch, so this leaves a lot of options to tweak any headphone to your likening.
Remarkable also is that all these features are also available to external amplifiers connected via the XLR and RCA
outputs in the back. Altogether the device is feature packed but also very easy to use with the intuitive UI and very
responsive touch screen.

Sound impressions & Comparisons:

Impressive build, specs & features but how does it sound? To be honest there is no simple answer. When using the X9
in bypass mode, without any EQ and crossfeed options it sounds very neutral, with good technicalities, nice soundstage
and very controlled and impactful bass. The fun factor will kick in when engaging those crossfeed & Eq functions which
will give almost endless options to tailor the sound to your likening. Driving power is more than enough for most
headphones and IEMS on the market. There are no issues whatsoever with background noise even with sensitive IEMS, the
background remains pitch-black in any circumstances. Judging the quality of the AMP and DAC sections in isolation,
i would say that the AMP in the Luxsin performs slightly below the excellent Aune S17 Pro (799€), this one is a
more powerful discrete class A amplifier it drives headphones with more authority and effortlessness, it sounds also a bit
warmer compared to the amplifier in the X9, these slight differences become more apparent with difficult to drive
headphones like the HE-6 SE V2 from Hifiman, a very power and current hungry planar driver headphone. Here
the X9 clearly struggles to drive them properly and falls a bit short. The DAC on the other hand is a very solid
performer, it's right up there with Dacs like the Topping D70 Pro Octo (599€) in regards to detail, resolution and imaging.
It takes the kinds of a Volumio Preciso Dac priced at 799€ to slightly outperformed the qualities of the X9.
At a similar price there are not to many options when it comes to Dac/Amp combo units, so the only two units that
i could bring in for comparisons are the Topping D5 II & Fiio K13 R2R. I have both units on hand but didn't have the
time for a deep dive yet, but on first impressions i must say that the D5 and K13 are both exceptional units for their
asking price at around 300€, alone from a sound perspective they are not that far away from the X9, for sure they are not
as rich when it comes to features & build quality but in terms of sound they really surprised me. A nice and close
competitor would certainly be the Topping DX9 Discrete a similar priced and very attractive looking unit, i will try
to get my hands on that one and in case i do that would be an evenly & interesting contest for sure.

Verdict:

As a conclusion the Luxsin X9 is without any doubt a feature packed device delivering great sound quality for its price.
It's certainly a beautiful peace of gear to sit on a desktop & with all it's EQ & Crossfeed functions it's a great choice.
There could be two use cases where you should also consider looking elsewhere, firstly if you are trying to pair it with very demanding
headphones and secondly if you like the sound signature of your headphones and don't want to mess with the features mentioned
above and prefer a simple solution.

Specs:

Dac Chip: AKM AK4191+AK4499EX
USB interface: XMOS XU316
DSP chip: AK7739
OP AMP: OPA1612
Amplification chip: TPA6120A2
Bluetooth chip: QCC5125

Inputs: 1x USB-C, 1x USB-B, 1x HDMI ARC, 1x Toslink optical, 1x Coaxial, 1x Stereo RCA
Outputs rear: 1x RCA output (line/preamp), 1x XLR output (line/preamp), 1x Subwoofer output (RCA)
Outputs front: 1x SE 6.35mm jack headphone output, 1x Bal 4.4mm jack headphone output,
1x Bal XLR 4-pin headphone output

Output Power: 4000 mW @ 32Ohm Balanced 4.4mm & XLR output
Dynamic range & SNR: >128dB. THD+N: Under 0.00016% (-116dB)

Supported sample rates: USB: PCM up to 32bit 768kHz, DSD up to DSD512
Toslink optical / Coaxial: PCM up to 24bit 192kHz, DSD up to DoP64
HDMI ARC: PCM 24bit 192kHz

Supported Bluetooth codecs: SBC, AAC

OS compatibitliy: USB : Windows (10, 11), Android, iOS

Network Connections: WiFi

Dimensions: 300 x 206 x 65mm
Weight: 3.72kg
Colour: Silver