xDuoo TA-20 Plus is a hybrid headphone amplifier that aims to successfully combine the smoothness of tubes with the power of transistors. As an idea, this sounds great. Who wouldn’t like to get the best of both worlds? While marketing is one thing, and reality another, given a good track record with previous xDuoo amps I’ve tested, it’s not foolish to believe they might pull it off.
Build and Features
xDuoo TA-20 Plus features an all-metal build. It needs to host a big transformer in its trunk, and three different tubes. One of those tubes is quite big itself mind you. Given that, it is understandable that this amplifier is going to be a bit chunky in its appearance. When it comes to tubes, you can either leave them exposed for views or cover them with a protective cage. Good thing for people with small children or pets.
The front panel hosts three types of headphone outputs. One of these is a good old single-ended 6.3 mm out. The other two are balanced, they come in the form of XLR and a 4.4 mm jack. The dot-style two-digit display looks nice in my opinion. The real, analog, VU meter in the middle does too.
In the back, we can find two sets of single-ended RCA inputs. Then there is a set of balanced XLR and 4.4 mm inputs that are worth using if you can. That’s because TA-20 Plus features a fully balanced design and can benefit from getting that differential signal. Finally, one set of RCAs is reserved for the line-level analog output. Very versatile device indeed.
The rated power of TA-20 Plus is up to 2600 mW when balanced output is used. Single-ended output still goes up to the respectable 2000 mW. If you’re not so good with numbers and their meaning, this is a lot of power that will not leave you wanting more. The tubes in use are 5Z4P and two of 12AU7. The first one is a rectifier while the other two are for signal amplification. Given this is a hybrid amplifier, there is a class A transistor buffer in the end, providing good current potency. This means that this xDuoo will not have any issues driving very low-impedance headphones. That’s something that can be troublesome for tube amplifiers.
Number buffs can look at more technical details in the spec table below the review. Now we move to the real-life performance.
Sound
Let’s start with the out-of-the-box experience and with factory-supplied tubes. The sound of xDuoo TA-20 Plus is full, pleasantly warm, and very smooth. That fullness comes from a very healthy bassline. Bass notes go quite deep and they are well-behaved. Control of these deep notes is not as firm and revealing of inner tone texture as you would get from the best solid-state amplifiers at this price. But listen to it in isolation and you will not lack definition. If anything, a dose of pleasant warmth can often do more for your musical enjoyment than having clinically precise bass.
Midrange strikes a very good balance between fullness and clarity. Vocals are pleasantly thick and instruments pleasantly bold. The amplifier is still quite informative and brings enough fine details from the recording. It just never double-downs on those details as some more analytical amps do. The highest frequencies are well extended but smooth and natural. This only adds to the warm and cozy nature of this amplifier.
The soundstage is decently wide and well-layered. It’s quite in line with what I expect from an amplifier of this price. Layering and separation of instruments are decent too, but some opponents can sound more open and arier. This is very closely connected to the laid-back nature of the highest frequencies.
Finally, dynamics are strong too. This is not an amplifier that will make you jump with the beat, but it will never sound flat and boring either.
Tube Rolling – Apos Ray Tubes
Now let’s move from the factory-supplied 12AU7 tubes to the aftermarket Apos Ray. The bassline gets slightly tidier but doesn’t lose its warmth, which is good. Midrange and highs are where bigger changes happen. The midrange is now more revealing with more inner tone texture. Things like wind instruments or vocals now have more of that realistic tone to them. Let’s take Sade as an example of a vocal with that rich, almost sandy, inner texture. This kind of detail is more obvious now. Finally, the highest frequencies gained more extension. This results in the sensation of a bigger and airier soundstage.
We gained more tone texture, more air, and better soundstaging. We didn’t lose any smoothness and naturalness in the process. So This particular tube-rolling experiment was a success in my opinion. There are many more tube options out there on the market of course. A review like this one can never cover all of them. Tube rolling can be a hobby on its own, for better or worse.
Comparisons
Topping L70 is a more affordable solid-state amplifier at $350. It’s a powerful one too. These two amps share some tonal characteristics. Both present basslines in a full and slightly warm manner. Both are informative in the midrange, but not leaning too heavily on the edges and sharpness. They’re more about sounding natural. Upper midrange and highs are where the most noticeable difference is. TA-20 Plus has sparklier and more extended higher frequencies. Topping L70 sounds darker and almost dull in that same region, in a direct comparison. Given that TA-20 Plus is not overly bright by any meaning of that word – I say that xDuoo is simply striking a better sound balance and more revealing upper frequencies. On top of that, there’s more time domain liquidity and natural tone flow with TA-20 Plus.
Topping A90D is Topping’s flagship and is more expensive at $599. Can it defend the honor of solid-state design? It’s yes and no. First of all, the A90D is tonally a more neutral amplifier. It’s also more revealing of tiny details, it offers quicker transients and better sensation of the inner tone texture. Wind instruments like saxophone, for example, will sound richer with sandy-sounding harmonics. Technically speaking, A90D wins this duel. On the other hand, TA-20 Plus counters with a fuller tone body, and once again with smoother and more liquid tones. Cymbal hit sounds clearer on A90D for example, but it also has some of that grainy quality. TA-20 plus makes it more continuous in time – making Topping’s tones appear rough in comparison. To cut the story short, Topping A90D brings more technical excellence and digs more stuff from the recording. TA-20 Plus is not as revealing but makes all of that sound more natural.
Now, all of this was with default tubes. If I put the Apos Ray tubes mentioned above in the xDuoo – the sound opens up and becomes more neutral. TA-20 Plus catches up with Topping A90D in terms of fine details, tone texture, and airiness. However, it still keeps its tube-specific quality of smoothness. The final result is that I slightly preferred TA-20 Plus with Ray tubes over Topping A90D.
Conclusion
xDuoo TA-20 Plus is a device of many qualities and very few flaws – if any. While it’s very good in its default state, some careful tube rolling can make it truly great. But anyone hooked to tube designs will tell you that’s part of the fun. All in all, xDuoo TA-20 Plus is a great product that comes highly recommended.
XDUOO TA-20 PLUS – CHARACTERISTICS |
Single-Ended Headphone Output : Balanced Headphone Outputs: Suitable Headphone Impedance: 16 to 600 Ohm
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