xDuoo DM-01 Robot DAC & HP Amp

[RogerSmith]

Funny product, so this is definitely a tube amp where the distortion is audible and apparently not very pleasant (although only even harmonics).
By the way, I am astound Amir is listening to techno, or is this only a test track?

 

[amirm]

By the way, I am astound Amir is listening to techno, or is this only a test track?

Both. I don't listen to ton of it as it can be repetitious but do enjoy some. For testing, I use them as test of upper bass performance.

 

[JSmith]

although only even harmonics

Any system nonlinear enough to produce harmonics (e.g., 2nd, 3rd harmonics from a sine wave input) is also nonlinear enough to produce intermodulation products when more than one tone is present.


JSmith

 

[Billy Budapest]

Well apart from the novelty design, this is not great... I assume the owner got it for his/her kids and sent it in for a bit of fun.

I hope it brought a smile @amirm whilst testing it.

This is the back;

View attachment 462139

View attachment 462140


JSmith

Perhaps if transistors were used for amplification and the tube used as the buffer stage, fidelity would be better.

 

[SuicideSquid]

Seems like the digital portion is well-implemented, the tube portion is a tube, and the formfactor is great. If you want to play around and experience "tube sound" this seems like a reasonable way to do it.

I only noted "not terrible" though as the objective performance, though in line with tube gear, is not good.

 

[amirm]

Wish they had designed a tube bypass. It could come in the form of a bigger brain or something.

 

[xema]

expecting a headphone plug hole in front of its crotch (

 

[wwenze]

Perhaps if transistors were used for amplification and the tube used as the buffer stage, fidelity would be better.

The two terms are somewhat interchangeable. And probably the same result. Small signal tubes hate low impedances.

And what's the point of the tube if the sound doesn't distort?

 

[Saponetto]

Oops.
Just found "something with tubes" I don't like...
Thanks a lot for this interesting review @amirm!

 

[Koeitje]

Probably makes all vocals sound like robots with that amount of distortion.

 

[JSmith]

Probably makes all vocals sound like robots with that amount of distortion.

JSmith

 

[Count Arthur]

"Missed opportunity to have it be a graphics display saying robot stuff" lol

There you go:

 

[AdrianusG]

Great design, but unfortunately they just "had"to screw up measurements with that tube in it

 

[AdrianusG]

There you go:

View attachment 462177

If it could really display this text i might still buy it though LOL

 

[DSJR]

That's pitiful performance even for tubes FFS, so it must be a design choice! No reason at all why distortion couldn't be in the 70s or 80s at least if not higher, so then basically inaudible...

 

[AudioSceptic]

This is a review, detailed measurements and listening tests of the xDuoo DM-01 Robot DAC and hybrid tube headphone amplifier. It is on kind loan from a member and costs US $237.
View attachment 462095
As you see, the product is aptly named! The arms are actually functional with one being on/off and then other, selection between USB and Bluetooth. The "ears" control the up/down volume control. The torso shows what you see with color changing depending on mode. Missed opportunity to have it be a graphics display saying robot stuff.

What follows is a bit of abbreviated measurements in the interest of time.

xDuoo DM-01 Measurements
Let's start with the DAC section, taking output from the rear aux terminal and setting the volume to 2 volts nominal:
View attachment 462098
I had forgotten for a moment about that tube and was shocked at the level of distortion. That sinks the SINAD at the bottom of our 400+ DACs measured to date. Won't bore you with the graph.

Dynamic range though, was surprisingly good:
View attachment 462101

As was frequency response:
View attachment 462103

Intermodulation expectedly, not:
View attachment 462104

Headphone output partially redeems itself with good amount of power:
View attachment 462105
View attachment 462106

I was relieved that the output impedance was near zero:
View attachment 462107

XDuoo DM-01 Listening Tests
When you get one chance to listen to a robot DAC, you take that opportunity! I only tested it with my Dan Clark E3 headphone. Despite its low sensitivity, the DM-01 had no trouble pushing a ton of volume out of it. At low listening levels, or when only bass was playing, the fidelity was good. But have that combine with vocals and they were quite gritty. As was the bass in techno music at elevated levels. During same passages, high frequency notes almost became unlistenable due to their harshness.

Net, net, if you don't listen too loud, it may be OK.

Conclusions
After measuring hundreds of similar looking black metal boxes, it is a pleasure to see an out of box form factor. Wish the tube was not there as it would make it much more performant and robust in the hands of younger people. Still, some may like the combination.

While I won't go and buy one for myself, the xDuoo DM-01 makes for a nice novelty gift or conversation piece on your office desk.

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As always, questions, comments, recommendations, etc. are welcome.

Any donations are much appreciated using: https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

Nice novelty gift??? Maybe for $23.70, not $237!

 

[Bland_username42069]

Impressive levels off “dynamic slam” and musicality even if lacks the rhythmic punch of more expensive cybertron DACs.

 

[Multicore]

A not boring DAC. Bravo!

 

[Sokel]

If it could keep its distortion minimum of -62dB and pattern up to 500mV instead of about 150mV I would bet that it could be ok with music, without nasty surprises.

Design is... (better keep my mouth shut) .

 

[AdrianusG]

If it could keep its distortion minimum of -62dB and pattern up to 500mV instead of about 150mV I would bet that it could be ok with music, without nasty surprises.

Design is... (better keep my mouth shut) .

Oh common, it's fun, why so serious