Today, Lynn reviews the xDuoo XA-02, a compact desktop ES9039Q2M DAC and balanced headphone amplifier capable of up to 2W output power.
Disclaimer: This is a sample sent in exchange for my honest opinion. Headfonics is an independent website with no affiliate links or status. I thank Shenzhen Audio and xDuoo for their opportunity.
Click here to read more on xDuoo products that we have previously reviewed on Headfonics
This article follows our current scoring guidelines which you can read in more detail here.
xDuoo is known for producing powerful headphone amplifiers at many levels.
Still one of my favorites is the xDuoo TA-30, which is, to put it mildly, insanely powerful with the ability to drive the hardest of the hard headphones.
Many of their other models run with tube setups like the MH02, TA-26, or recently released portable XD05T reviewed by Louis. Others such as the XA-10 follow the solid state path.
The XA-02 follows the familiar solid-state path, with plenty of power backed by multiple connectivity options. Thankfully, this is the approach many on the market are taking.
This was a fun amplifier to put through its paces, and what follows are my impressions and comparisons to notable budget competitors such as the SMSL DL100.
Features
The xDuoo XA-02 is a balanced topology DAC and Class A headphone amplifier with wireless BT5.1 capability.
With balanced circuitry (and isolated from electrical interference), the output in balanced mode is an impressive 2000mW (suitable for headphones between 16Ω to 600Ω) and up to 910mW (single-ended).
The XA-02 also has a three-step gain switch within the “sub-menus,” after pushing the red volume knob. Each setting provides a reasonable jump in volume, but I do not know by how many dBs each level is raised.
I found the XA-02 could easily drive the SJY Horizon without issue. With multiple input and output options, the XA-02 is quite versatile and can used for more than driving headphones and IEMs.
The xDuoo XA-02 is equipped with a single ESS ES9039Q2M DAC capable of PCM up to 32bit/384kHz, DSD256, and MQA 8X, falling slightly behind the powerhouse portable XD05T that Louis reviewed recently. The DAC section also has eight selectable filters which are subtly audible to me.
For Bluetooth connectivity, the XA-02 employs the BT5.1 capable QCC5125 SoC with codec handling up to LDAC, including aptX HD and LL options.
Design
xDuoo carries on their now traditional darker-gray aluminum frame construction, which includes vertical slots on some parts. In this case, those slots are on the front face, breaking up the pattern nicely.
What looks like side “drilled” holes are canted into the rounded top for ventilation purposes. I did note that the Class-A amplifier can become somewhat warm during hard driving, as is typical with that class of amplifier. Slots on the bottom help to dissipate any potential heat build-up, too.
This follows the xDuoo design pattern, with a modern twist showing off those holes, helping to break up the form.
Form factor
Those vent holes can help when placing the XA-02 in multiple-gear situations, allowing the heat to circulate around anything that is placed on top that shares similar size characteristics (20× 17.5× 4.7CM, 0.9kg).
That smaller footprint allows the XA-02 to be used in a multitude of situations, but keep in mind there is no remote. So keeping the unit close at hand is a must, besides seeing the smaller centered screen (1.3” OLED) for operations.
Aesthetics
The red volume knob (multi-function) is also a traditional xDuoo look on DAC/amplifiers in this class for the company.
It helps break up the all-gray front, except for the gold-lined headphone jacks. Other than those jacks, the only two items on the front are the “menu” button and “pairing” button for BT.
Pushing that red volume knob changes the source input, and the only access to the menu is through the small button to the left of the volume knob.
While the volume is digitally run, I found that it was not accurate sometimes, with the numbers (and corresponding volume) increasing by many with a single detented move.
A better option would be a pure resistor for smoother operation in my mind. That said, once used to that “discrepancy,” I was careful in turning the knob.
Access to the inputs and outputs is on the back, as is the on/off switch, which leans towards keeping the whole unit accessible in your system. This is where a remote would have helped the most in my opinion.
I/O
The XA-02 provides a good amount of connectivity upfront and on the rear panel. Upfront you can see two headphone ports, a full-sized 6.35mm plug, a 4.4mm balanced connection, and the mentioned menu and BT small buttons. The red volume knob shows like Rudolph’s, and I do like that aspect.
The back carries the business of source inputs and outputs efficiently. With RCA Aux-out on the left, you can exit the XA-02 into another option such as a home amplifier if you wish.
Inputs of Coax, optical, and USB-C continue left to right, with plenty of space between these ports. The BT antennae lies above the USB-C input with plenty of room to angle it.
Next to the USB-C is the data USB-C connection for updates with your laptop or PC. Next to that array is the power plug insert and on/off switch.
While I wish for RCA inputs, having the now ubiquitous USB-C presents itself as quite versatile and my main connectivity point.
The on/off switch is equipped with POP technology, preventing the large “pop” often associated with turning such units on or off.
The front headphone jacks balance the panel nicely with easy access to any buttons on the front, other than the smaller size of the two function buttons.
Connectivity
Bluetooth
The Qualcomm BT5.1 connected seamlessly to many sources ranging from the FiiO JM21, Shanling M6 Pro, and my MBP. I was also able to BT from the FiiO TT13 for use with headphones, and out to a pair of Edifier R1280DBs powered speakers, using the AUX out on the XA-02.
Latency was commendably low as I watched Netflix or YouTube videos of various content using the Shanling. Streaming Tidal or Qobuz proceeded without issue as did native SD card music.
USB-DAC/OTG
Using the USB-C was my main listening option due to the limitations of gear I had on hand. However, I was also able to AUX-out to the above-mentioned Edifier R1280DBs (updated version) powered speakers.
Connecting sources from the USB-C was immediately recognized no matter what the source was and I was up and running in no time as a result.
Controls
The 99-step volume knob functionally works to let you know when you have changed the volume, while the numbers come up on the 1.3” screen in bold numbers, as well. I do like the detented feel, but wish it was more accurate.
Used as a focal point though, the red knob gives you a reference point for accessing the two function buttons just to the left, between it and the screen. Again, there is plenty of access room, and I had no trouble accessing the switches without issue.
When pushing the rectangular menu button you are presented with three options: filter choice, gain, and a bass filter. Using the volume knob to move between each, you then push the red volume knob to change each function.
Filter changes were subtle but allowed for changes ranging from added bass, to a more frontal mid, or extended soundstage. While changes could be heard subtly, I kept the unit on filter 4 for added spatial awareness or filter 7 for a seemingly smoother signature (besides the ESS chip).
Packaging & Accessories
The XA-02 came in a white box, protected by a thick plastic shrink. Inside the usual medium-density foam cutouts protected the unit and gear from damage, with the XA-02 wrapped in an opaque plastic sleeve for added protection.
The two plastic Ziploc bags contained the power cord, a USB-C to USB-A cable, the BT antennae, and the owner’s manual/warranty card. A 3.5mm to 6.35mm jack adaptor was inside another small Ziploc bag.
Sound Impressions
Listening impressions were made using the SJY Horizon (4.4bal using an XLR adaptor) and Meze Audio 99 Classics (4.4bal cable) headphones, the Campfire Audio Solaris 2020 (ddHiFi Nyx Net cable), and Edifier R1280DBs powered speakers.
Sources included the FiiO JM21, Shanling M6 Pro, MBP, and the FiiO TT13. Streaming was done using Qobuz (JM21), Tidal (others), or YouTube videos.
Summary
Headphone amplifiers that use ESS chips are normally on the warmer side of the listening spectrum, and the XA-02 is no different. Using ELNA capacitors contributes to this warmish tonality, but not so much that the signature is too smooth.
Instead, the XA-02 exudes a mature sound that sounds good across various genres, without minimizing each genre’s impact on the sound.
In other words, a brighter, more energetic sound still comes across with a bit of verve, just not as much as a DAC/amp with a brighter tone to it, might. Instead, the signature still emulates the intention quite well.
Bass reaches fairly low, and lower yet with the Bass switch turned on, which adds about 6db to the weight. This addition is not so much as to overshadow most tones moving into the midrange, or upper end of the bass spectrum, presenting good weight to the notes.
The midrange is set slightly back from the rest, which is again a characteristic of the ESS chip to me. Instead of hiding though, the mids tie together each end nicely, especially with the polite top end present in the XA-02.
The precision that the XA-02 provides goes a long way towards not making this simply another warmer-sounding amplifier.
Timbre
The rich, slightly warm signature presented throughout the range on the XA-02 is not so overwhelming as to become drippy or slow. Instead, the already warmer tendencies carry forth an organic, natural signature that provides for the intended musicality to shine.
The sound emanating from the XA-02 is almost TA30-like with its warmth, but without the bright top end, or too-smooth-sometimes signature coming forth.
Instead, there is a balance of richness, that pervades while offering excellent spatial tendencies. This allows notes to spread out, giving excellent weight to attack/decay characteristics. Accuracy with aplomb would be an apt way to describe the warmer tonality.
At the extremes though, this warmer tendency can hinder some of the softer-sounding instruments such as in a jazz trio or quartet.
Much of this can be attributed to the softer play within the genre, but the XA-02, while very good, should not be one for extreme accuracy or a tendency towards analytically succinct sound.
What it does is present a very musical mixture of sound that while accurate, allows the listener to enjoy what is heard instead of focusing on the accuracy. This is a highly musical amplifier.
Staging & Dynamics
The overall appeal of the XA-02’s soundstage is the cubic effect, without highlighting any one spatial dimension to me. The depth is equally as good as the width or height. This affords an excellent space for the instruments to spread out, showing off their wares.
Add in very good weight to the notes, and you have a full spatial representation, without any one direction overreaching too much.
The equal effect also helps with very good clarity heard across the three dimensions. Clarity when taken in this vein is very good, and I think a large part of this is due to the tighter control of the lower frequencies.
The XA-02 allows each part to become a needed aspect of the whole. It is often said the sum is greater than the parts, and this would be one of those instances.
Conversely, when using that terminology, this can act to cover less stellar parts, hiding deficiencies. Not so here, since the synergy between the musical parts and the cubic spatial representation affords equal time and space to all.
The imaging affords the listener’s ability to place with accuracy each part, but not in isolation. Rather part of the whole, which again makes for a thoroughly musical experience.
Click on page 2 below for my recommended pairings and selected comparisons.