• WANTED: Happy members who like to discuss audio and other topics related to our interest. Desire to learn and share knowledge of science required as is 20 years of participation in forums (not all true). Come here to have fun, be ready to be teased and not take online life too seriously. We now measure and review equipment for free! Click here for details.

AudioQuest Dragonfly Cobalt Review (Portable Headphone Adapter)

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
32,170
Likes
106,294
Location
Seattle Area
#1
This is a review and detailed measurements of the AudioQuest Dragonfly Cobalt portable DAC and headphone amplifier ("dongle"). It is on kind loan from a member and costs US $300.

The Dragonfly Cobalt dates way back to when these dongles came in the form of USB flash Thumb drives:

Audioquest Dragonfly Cobalt Review DAC and Headphone Amplifier.jpg


This makes it easy to connect to desktop and laptop computers (assuming yours has such USB connection) but needs a chunky adapter to connect to USB-C on phones and tablets. While I did not have it, a custom one comes with Cobalt which makes a secure connection.

The dragonfly series comes in a few colors, each with a different performance level. The Cobalt is the top of the line as indicated by sky high price for such a product. An ESS ES9038Q2M DAC chip is used internally as to indicate high performance. We will check for this. :)

AudioQuest Dragonfly Cobalt Measurements
I was pleased that the Cobalt introduces itself to Windows in a way that I could use my ASIO interface layer and as such, run my full suite of tests (which half the time I can not). Let's start with our dashboard:

Audioquest Cobalt Measurements DAC and Heapdhone Amp.png


Looks pretty bad. It actually looked far worse before I subtracted 1 dB from the digital input signal. Without it, it was heavily clipping with SINAD dropping to below 30! As it is, the Cobalt turns in one of the worse distortion ratings as encapsulated in SINAD that I have tested:

Best headpone adapter review 2021.png


The one to its right, Speaka, is one of the first dongles I ever tested. I think it cost just $30 or something. Sweeping the input level we see the full range of performance:

Audioquest Cobalt THD+N vs Level Measurements DAC and Heapdhone Amp.png


You can see that performance is best when the output is low and progressively gets worse until it hard clips. Just unacceptable.

Surprisingly, noise level is quite good:

Audioquest Cobalt DNR Measurements DAC and Heapdhone Amp.png


Distortion is the problem as we see in multi-tone test yet again:

Audioquest Cobalt Multitone Measurements DAC and Heapdhone Amp.png


DAC filter is slow, ala MQA style:

Audioquest Cobalt DAC filter Measurements DAC and Heapdhone Amp.png


I don't know how they consider 6 dB droop at 20 kHz acceptable. Testing with a square wave shows the "benefit" or no pre-ringing but with clipping as the filter rings:

Audioquest Cobalt DAC square wave Measurements DAC and Heapdhone Amp.png


Notice the flattening of the tops of oscillations. And that is at -2 dBFS input signal!

Linearity test is nailed showing once again, there is some good in this DAC that is obscured by other parts:

Audioquest Cobalt Linearity Measurements DAC and Heapdhone Amp.png


Jitter test shows very good results for a dongle as well:

Audioquest Cobalt Jitter Measurements DAC and Heapdhone Amp.png


Dragonfly Cobalt Headphone Amplifier Measurements
Most important measurement for these dongles is power. Phones and tablets often struggle to drive fancy headphones so the job of these products is to remedy that. Let's start with 300 ohm load:

Audioquest Cobalt Power into 300 ohm Measurements DAC and Heapdhone Amp.png


Distortion rises very early one starting at a fraction of a milliwatt -- totally unacceptable. Fortunately because the output level reaches to 2 volts, we do have good bit of power for a dongle:

Best headphone adapter 300 ohm.png


Performance drops much more with a 32 ohm load:

Audioquest Cobalt Power into 32 ohm Measurements DAC and Heapdhone Amp.png


Best headphone adapter 32 ohm.png


Compare the 26 milliwatt to recently reviewed THX Onyx. The Onyx produces 132 milliwatts compared to just 26 for Cobalt and does it at far lower distortion.

Dragonfly Cobalt Listening Tests
The Cobalt had no trouble driving my Sennheiser HD-650 to good levels of loudness and authority. There was not much to complain about in the context of a portable dongle. Switching to Ether CX headphone though, was a completely different situation. Turning up the level beyond a whisper would cause the bass notes to distortion. At max volume, the output was severely distorted and unusable.

Conclusions
As the category leader, AudioQuest takes advantage of their market position to price the Dragonfly Cobalt sky high. Unfortunately it then proceeds to deliver a highly distorting product that has little ability to drive low impedance headphones. You can buy plenty of products at one third of its price that way outperform it. If you want a brand name, get the THX Onyx which washes the floor with it. Whoever designed the headphone amplifier in this product needs to go back to engineering school or pay attention to what the competitor is shipping. Actually he needs to do both.

While with high impedance headphones, the AudioQuest Dragonfly Cobalt has acceptable subjective performance, it fails in so many other ways that I cannot recommend it.

------------
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/
 

polmuaddib

Active Member
Joined
Mar 1, 2020
Messages
176
Likes
195
#5
Thanks. If I remember right, all of the Audioquest products tested here were either flawed or mediocre at best, but overpriced.
I appreciate that ASR is demasking the high end market and showing that most of it is just good marketing and nice industrial design.
 
Joined
Jan 10, 2021
Messages
58
Likes
99
Location
Netherlands
#8
Audioquest products don't perform well when tested on ASR so it suprises me that many reviewers give high praise to Audioquest products.
Fortunately, we have Armir who shows us the truth.
Thanks Armir, keep up the good work.
 

respice finem

Addicted to Fun and Learning
Joined
Feb 1, 2021
Messages
519
Likes
612
#9
...As the category leader, AudioQuest takes advantage of their market position to price the Dragonfly Cobalt sky high. Unfortunately it then proceeds to deliver a highly distorting product that has little ability to drive low impedance headphones.
Category leader, yeah... thanks for the warning... My first thought after reading was "fail", then I recalled the review of this one https://www.audiosciencereview.com/forum/index.php?threads/e1da-9038d-review-portable-dac-amp.21556/ costing 1/3 of the Audioquest, and my second thought was "epic fail"... :facepalm:

That said, AQ will probably be selling better because of their "reputation", but for how long, if this "trend" continues?

It would be interesting to know what exactly causes the big differences between these two, one would expect the internals of such devices to be very similar, perhaps even the same chips?
 

Veri

Major Contributor
Joined
Feb 6, 2018
Messages
7,297
Likes
8,605
#10
one would expect the internals of such devices to be very similar, perhaps even the same chips?
Not at all. It's all in the implementation, the details definitely matter. If they wanted to R&D something proper with no cost cutting they could have, instead they made something half-assed and spent the money on the blue enclosure and marketing.

The article I linked above shows some teardown details by the way :)
 

Ajax

Member
Forum Donor
Joined
Aug 14, 2018
Messages
40
Likes
100
Location
Sydney, Australia
#12
Thanks Amir,

Your review confirms / supports those by @mansr (referred to above) and Archimago.

http://archimago.blogspot.com/2019/08/measurements-dragonflies-audioquest.html#more

I own the red dragonfly and admit to enjoying its sound and convenience, however, the SMSL dongle that I also bought at half the price is superior in ever way.

The overriding impression I get is that Audioquest products are not well engineered and that they are at the high cost / low value end of the HiFi spectrum.
 

Tks

Major Contributor
Joined
Apr 1, 2019
Messages
2,530
Likes
3,872
#13
The E1DA Balanced version I think is missing from the graph of devices for some reason.

As for the Dragonfly.. How are you going to opt for an ESS chip, yet not use the default and pretty well done brickwall filter they offer? At least then the 7db drop at 20Hz would be palatable, but why such a drop and the filter being slow to attenuate on top of that unfortunate effect?

As for noise being low but distortion being high, it would be odd if a portable device somehow was creating lots of noise, since it will usually not be hooked up to mains sources. But that distortion though.. Bossman said it best:

Whoever designed the headphone amplifier in this product needs to go back to engineering school or pay attention to what the competitor is shipping. Actually he needs to do both.
 

Jimbob54

Major Contributor
Forum Donor
Joined
Oct 25, 2019
Messages
5,554
Likes
5,991
#14
IIRC I think I might have found ASR when debating getting this and doing some research. Saved me some money back then when the review of black or red wasn't good.

Cost me a fortune too
 
OP
amirm

amirm

Founder/Admin
Staff Member
CFO (Chief Fun Officer)
Joined
Feb 13, 2016
Messages
32,170
Likes
106,294
Location
Seattle Area
Thread Starter #16
As for the Dragonfly.. How are you going to opt for an ESS chip, yet not use the default and pretty well done brickwall filter they offer?
Due to support of MQA, they are using the same filter for all content, MQA or not.
 

YSC

Addicted to Fun and Learning
Joined
Dec 31, 2019
Messages
978
Likes
647
#19
I am just guessing, will audio quest be tuning it to perform best at low out as most ppl who buy these dongles are using good IEMs which normally only use the lower 30% of digital volume. Of coz even its best performing SINAD is bad, no excuse
 

Matias

Major Contributor
Forum Donor
Joined
Jan 1, 2019
Messages
2,084
Likes
3,027
Location
São Paulo, Brazil
#20
There are several dongles that measure way better and costs way less than the Audioquest ones...
 
Top Bottom