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CHORD Mojo 2 Review (Portable DAC & HP Amp)

Rate this product:

  • 1. Poor (headless panther)

    Votes: 7 2.7%
  • 2. Not terrible (postman panther)

    Votes: 25 9.5%
  • 3. Fine (happy panther

    Votes: 122 46.6%
  • 4. Great (golfing panther)

    Votes: 108 41.2%

  • Total voters
    262

staticV3

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Is it possible to get descent output from these cans with the Mojo?
For the ATH-AP2000Ti we unfortunately have only manufacturer-provided specs. Using those we can calculate the expected peak SPL achievable with the Mojo 2, which is 125dB SPL (bonkers loud, hearing damage territory).

For the Aeon 2, same thing unfortunately. DCA claim 13Ω, 92dB/mW, which gives us 118dB SPL peak (painfully loud).

And for the Stealth, we can use Amir's data (23Ω, 99.2dB/Vrms) to get 109.5dB SPL peak (fairly loud).
 

Distordera

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For the ATH-AP2000Ti we unfortunately have only manufacturer-provided specs. Using those we can calculate the expected peak SPL achievable with the Mojo 2, which is 125dB SPL (bonkers loud, hearing damage territory).

For the Aeon 2, same thing unfortunately. DCA claim 13Ω, 92dB/mW, which gives us 118dB SPL peak (painfully loud).

And for the Stealth, we can use Amir's data (23Ω, 99.2dB/Vrms) to get 109.5dB SPL peak (fairly loud).
Wow, thanks! Really helpful. Is there something to say about distortion when you crank up the Mojo to these levels?
 

staticV3

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Is there something to say about distortion when you crank up the Mojo to these levels?
Only that I used WolfX-700's measurements and defined the clipping point "at the knee", which gives more pessimistic results for output power vs Chord's own specs.
(I maked the clipping point in cyan)
THDN-Ratio-vs-Measured-Level-3.png

For example, Chord claim 0.6W at 30Ω, which, according to Wolf's measurements, would only be reached by driving the Mojo 2 far into clipping territory at about 25dB SINAD.
 

Ken Tajalli

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Only that I used WolfX-700's measurements and defined the clipping point "at the knee", which gives more pessimistic results for output power vs Chord's own specs.
(I maked the clipping point in cyan)
View attachment 212414

For example, Chord claim 0.6W at 30Ω, which, according to Wolf's measurements, would only be reached by driving the Mojo 2 far into clipping territory at about 25dB SINAD.
Yes, the clipping point is at about 400mW in real terms, but the difference between 400 and 600mW is about 1.5dB if I am not mistaken.
FWIW, I used a Mojo2 with my Hifiman Edition XS (16 ohms, 90dB/mW), and I had no issues, it went loud enough, clean good sound.
I believe Dan Clark himself, on this thread, has said that the Mojo2 is up to the task of driving the Noire, but perhaps not the stealth!
If you can afford the stealth, you can afford a bigger amp to go with it. :)
 

Distordera

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Yes, the clipping point is at about 400mW in real terms, but the difference between 400 and 600mW is about 1.5dB if I am not mistaken.
FWIW, I used a Mojo2 with my Hifiman Edition XS (16 ohms, 90dB/mW), and I had no issues, it went loud enough, clean good sound.
I believe Dan Clark himself, on this thread, has said that the Mojo2 is up to the task of driving the Noire, but perhaps not the stealth!
If you can afford the stealth, you can afford a bigger amp to go with it. :)
Or maybe the opposite. Empty pockets. :) I have an RME adi-2 that will do fine when stationary.
 

Ken Tajalli

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Or maybe the opposite. Empty pockets. :) I have an RME adi-2 that will do fine when stationary.
What Da F...!
You are comparing a kilobuck desktop DAC to a portable one at less than half the price?
Of all the silly billies. :)
 

Ken Tajalli

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No no, not comparing anything. Just want to find a portable dac that will run a tough load with ease. Simple. :)
The issue is battery power, it is limited.
Also, for something like the Noire or Stealth, the impedance or rather the very low impedance can become an issue too.
To pump large power into a low impedance, low sensitivity headphone using battery power is very difficult.
Rechargeable batteries come in 3.7V LiPO, you can use two, as in the case of Mojo2 to have more voltage swing to create larger power output, but still it is not enough.
So designers go for Balanced operation & output. By doing so, they get to use the same battery voltage twice! Thus creating four times the power output (double the voltage swing, quadruple the power available).
But this comes at a price! The output impedance of a balanced output amp is twice the output impedance of a single ended amp. This higher output impedance becomes relevant when feeding a low impedance headphone such as Stealth. At least, like most planar headphones, Dan Clark headphones have a steady impedance, which helps a lot.
One needs to find a battery operated DAC/amp with balanced out, low impedance and high power, that fits into one's pocket with reasonable play time, to achieve this goal.
Offhand, I don't know any! It's a tall order.
 
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ClicketEKlack

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The test result is fairly predictable — you’re unlikely to hear the differences in a proper blind test between two well-designed DACs. The goal of the test is not to prove anything to others, but to prove it to yourself. Whether you lie about it or not is your business, but lying to yourself is just not healthy.
Just saw this. What happens when a blind test produces results that challenge the assumptions about what proper blind test results should reflect?

 

HarmonicTHD

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Just saw this. What happens when a blind test produces results that challenge the assumptions about what proper blind test results should reflect?

Unless the test is properly conducted (controlled ABX) and statistically proven, it is worthless. (See also some of the comments below the YouTube - although unpopular with the reviewer - they nailed it)

 
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Jimbob54

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Just saw this. What happens when a blind test produces results that challenge the assumptions about what proper blind test results should reflect?

I saw this yesterday. It doesn't work.

1. Participants were told there was at least one variable between the systems so naturally most said they heard a difference. No true audiophile could admit they maybe couldn't.
2. The "preference" was a coin toss. As one would expect when there is actually no audible difference. I'd love to see all the preference comments to see how polarised they were, not the edited highlights.

EDIT- I didnt watch closely enough- were there 2 pairs of identical HP in the rig, or one pair and listeners plugged into the different amps? If the former, then there may well have been audible differences- but between headphones, not USB cables.
 
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BDWoody

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Just saw this. What happens when a blind test produces results that challenge the assumptions about what proper blind test results should reflect?


Assuming it was properly set up and conducted, It would lead to further exploration to learn why.

In this case, the test wasn't done with the rigor required for it to mean anything at all, so nothing needs exploring.
 

pkane

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Just saw this. What happens when a blind test produces results that challenge the assumptions about what proper blind test results should reflect?


When someone says they can jump up 15ft from a standing start, I'd not be inclined to accept that claim without some major skepticism about the test parameters and results interpretation. This "test" is very much in that category.
 

Ken Tajalli

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Assuming it was properly set up and conducted, It would lead to further exploration to learn why.

In this case, the test wasn't done with the rigor required for it to mean anything at all, so nothing needs exploring.
Personally, I do not believe in sound quality differences between two proper USB cables, bits are bits in digital format, so a properly functioning digital cable can not influence the sound.
There is a minute possibility that one cable acted as antennae and picked up large amounts of RF, it then got injected into the analogue section of the DACs output section, highly unlikely though because as far as I know the DACs used (Chord Hugo TT2) have galvanic isolation on the USB input.
However, this brings me to another issue I tried to hint at in my previous posts:
- The fact that even the results of a level matched, blind tests will not be easily accepted, if it goes against our established beliefs!
We will try to pick holes in it to rubbish the results or at least put doubts in it.
I was impressed that you are keeping an open mind and declare that "further exploration (is needed) to learn why."
That is the scientific way.
 

Jimbob54

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The fact that even the results of a level matched, blind tests will not be easily accepted, if it goes against our established beliefs!
They'd be easier to accept if there was a decent attempt to remove all other variables.

And I don't think you read Woody's post properly.

IF the test was done properly, THEN the results would require further exploration.

It wasn't, so they don't.
 

Ken Tajalli

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They'd be easier to accept if there was a decent attempt to remove all other variables.

And I don't think you read Woody's post properly.

IF the test was done properly, THEN the results would require further exploration.

It wasn't, so they don't.
At least, he suggested further investigation under suspicion , and then the bias kicks in, (and he continues to say , but it wasn't , a guess) not outright blowing a raspberry!
For what its worth, I have a hard time accepting it too.
 
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Tarso

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I have a question that might seem absurd, but how does the Chord Mojo 2 compare to the RME ADI-2 FS?

I currently have the RME and adore it. It was one of those cases where I finally found something that suits my tastes, the sound I was looking for. The thing is: I'm going to be traveling a lot and staying in places for months at a time working remotely, so I am taking headphones and an amplifier.

Of course, the RME is way bigger than the Mojo 2, but it's not THAT big. But it would make an immense difference in convenience.

Has anyone had a chance to compare these 2?

My current daily drivers are HD650, Arya, and Focal Stellia.

Thank you so much for any input! =)
 

Ken Tajalli

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