Setup, Customization, and Performance

Given the xDuoo XD05T is a DAC/headphone amp/preamp unit, the number of cables that connect to the device are fully dependent on how you plan on using it. I suspect most readers of this review will be using it primarily with USB or Bluetooth for input, although the other inputs can be quite handy with non-desktop sources, such as a CD player or a phono stage. The smaller form factor and Type-C input also makes it easier to connect this to a mobile device, let alone laptops and desktops, with the integrated battery further helping cut down cables as needed. Turn on the device via the power switch and you will notice the display turn on simultaneously, going through a welcome screen and product name briefly before leading you to the home page that allows you to see the input mode, active filter, volume level, turbo level, battery level, and playback sampling rate as applicable. There is no system menu here for further customization, so in that regard the XD05T is relatively simple to set up to your desire and use as-is.


You will notice the tubes glowing almost immediately when the XD05T is switched on, and for once the manufacturer doesn't recommend a waiting time for the tubes to be fully warmed up before you start listening from the device. The vents help with passive cooling, but obviously also for the cool factor as you will undoubtedly stare at the orange glow within. For those wondering, the tubes went up to ~70 °C with turbo level set to high and driving the HIFIMAN Susvara Unveiled—yes, this can get it plenty loud—which is not bad at all for vacuum tubes. More importantly, the chassis was well below body temperature, meaning it remained cool to the touch and thus the heat from the tubes does not seem to be an engineering issue or a complication to your user experience. This is based on an ambient temperature of 20 °C in the UK right now, so keep in mind that those in tropical countries in the summer may find the chassis to be in the high 30s/low 40s °C at times. You want the heat from the tubes to transfer to the outside via the metal chassis, so this is a good thing either way. I'd say that you may just not want to carry the XD05T in your pocket while in use in those situations.


Using the xDuoo XD05T with Windows 10 or 11 doesn't require any additional drivers, with Windows recognizing the device automatically. We see that the default settings provide PCM playback options up to 32-bit, 384 kHz out of the box. The USB bridge comes in handy here, and all your favorite players will recognize the device in WASAPI (Windows Audio Session API) mode accordingly. There should be equivalent drivers pre-configured in newer macOS builds too, but I am not familiar enough to speak on this front.


If you have a device that doesn't accept UAC 2.0, or even if you simply want to try other options, then you can find USB audio device drivers on the xDuoo firmware downloads page where the latest version at the time of testing was v5.0.0—quite old compared to newer drivers available for the XMOS bridges today, if I say so myself. Installation is trivial as seen above, and these drivers now allow you to make the most of the xDuoo XD05T within the Windows operating system.



Installing the drivers creates a new output device in Windows as well as provides access to the xDuoo USB Audio Control Panel. Just be sure to set the format to your desired level and choose the ASIO (Audio Stream Input/Output) buffer size that suits your latency requirements. With that done, go to your media player of choice. I demonstrated above with JRiver again and set the audio player to the same output. At this point, you can implement further tweaks, but those are player dependent. For example, we see the ASIO drivers are also recognized by Roon, which is quite possibly the best thing you could have if you tend to go with local storage of music files over streaming. I have more or less replaced JRiver with Roon now for its various features and, If you are interested to give it a try, you can use this link to get a free 30-day trial (I don't get anything out of it). There is no first-party mobile app or desktop EQ support here, but you can always use your own EQ/DSP programs as usual. These drivers also provide 16-bit playback support if that is relevant to you.


Bluetooth connectivity worked as advertised too, with the Qualcomm SoC providing BT 5.1 support with SBC/AAC/aptX/aptX HD/aptX Low Latency/LDAC codecs on offer. I had no problem using my phone with the XD05T, as seen above. Obviously, going wired over USB would be the preferred method wherever possible.

Audio Performance

Now that we have gone through the capabilities and set up of the xDuoo XD05T, let's talk more about its capabilities in terms of driving headphones. The XD05T generally has worse objective measurements compared to typical solid state amplifiers, even those that use the same ES9039Q2M DACs, which itself is not a surprise to anyone who has used tube amps. Whether you can perceive these or not is a different matter altogether, and it depends a lot on your listening volume and music library. The XD05T is actually far cleaner in both measurements and subjective listening than most old school tube amps, and you can see this with the ultra-low output impedance of <0.2 Ω for either headphones output. This is why you can get away with using it with IEMs too, although I would not recommend it as a source for high sensitivity IEMs since there can be a slight background hiss here. Power output is highly respectable thanks to the three gain levels and a large volume range of control, putting the XD05T on par with some desktop sources even! Indeed, xDuoo rates the XD05T to provide up to 750 mW @32 Ω and 83 mW @300 Ω per channel off the 1/4" jack, with the equivalent numbers being 1.5 W @32 Ω, and 565 mW @300 Ω per channel for the 4.4 mm balanced output, which is more than what we saw with the FiiO K11 R2R, for example. Note that these are the max power ratings in the highest gain mode, so you can of course turn things down in lower gain settings. I had no issues using the XD05T with just the single-ended output for most IEMs and headphones on the market, including the relatively less sensitive Symphonium Audio Helios as well as some higher impedance headphones such as the FiiO FT3. More demanding headphones can take advantage of the balanced output, and I found better synergy with headphones that are tuned more neutral-bright including the $8000 HIFIMAN Susvara Unveiled, although pictured above is the even newer HIFIMAN Arya Unveiled (review coming soon). The best way to go about it is start off with low gain and work your way up only as needed to ensure you don't damage your ears or connected devices while also having a larger range of volume control.


I spent a few weeks using the XD05T with a variety of headphones and IEMs to fully test how it sounds, knowing already that it's not going to work best with ultrasensitive IEMs. The line out and preamp features worked very well, and I have no complaints on that front having used this with some active speakers. The frequency response leans slightly towards the highs funnily enough. It was quite consistent across multiple measurements, but I dare say the deviations from flat are not going to be perceivable. This is especially true when you realize the DAC section is already as neutral as it gets, with ESS doing a much better job in curbing down the tiny glare from its previous gen DACs. The biggest coloration to the sound will come from those tubes, and honestly this is one of the better implementations in balancing out a clean sound with some warmth. There's some deliberate increase to harmonic distortion, especially even-order ones, which can work nicely with some headphones to create a larger sense of stage in addition to allowing brass and string instruments to shine further. I noticed this especially with my jazz collection, although vocals were hit or miss with some arguably feeling slightly clenched. Most importantly, I never felt details were getting fuzzy or notes losing texture. It's not the most tube-y of sounds but does give you that taste so you can then decide whether to commit fully or not. For those wondering, the three gain levels don't affect the sound presentation beyond simply increasing the volume level. What does change things significantly though is that bass switch, giving up ~6 dB increase at 20 Hz but with a shelf that starts around 1000 Hz itself. This is this more of a bass + mids shelf, and I honestly found it simply too overwhelming and muddying things every time I used it. It's now late 2024 and multiple manufacturers are offering more customizable EQ options with their sources, so xDuoo can do better in this regard.