[TokenGesture]

Yes, either the coax or optical works great. You can get a low profile on either and now that the FW has been updated, have a very good source from the DX80. The sound is very clean coming from the DX80. 

Thanks! How are the stacking ergonomics?

 

[verber]

   
The famous «voltage swing»...

A buzzword with no technical meaning behind it. How do you actually know that the Mojo has a deficit there? And that the amps don't color the sound? I'm homestly interested in such an amp BTW.

 
Both Hugo and Mojo drive HE1000 and HD 800 with ease and to my full satisfaction – none of my amps does it better. I guess it depends on personal sonic preference and sonic ideals. To me every amp I attach to them makes the sound less accurate, but certainly more forgiving, thanks to the rounded edges providing a smoothness and «refinement» pleasing to the ears.
 
Maybe it's not easy to swallow, but euphony and accuracy aren't one and the same. Apart from that, some amps may indeed create a better tonal synergy with specific headphones than others, and this mechanism may also be in play here. But it would be a shame to not make use of the Hugo's/Mojo's unique feature to renounce a dedicated headphone amplifier in the interest of highest signal accuracy – there are alternative methods for modifying the sonic balance of a headphone to one's preference.
 
 
Yes, I can confirm that: To my ears the Hugo sounds slightly airier, more refined and threedimensional.
 
Indeed!

 

 
Summary: I am not suggesting that the Mojo needs to be used with a dedicated headphone amplifier. I have no plans to use an external amp because that would change the SQ-portability and SQ-price equation that I think the Mojo delivers very well. My statements about using an external amplifier were mostly a reaction against what I perceive as excessive enthusiasm for the Mojo (and the Hugo before it) resulting in people over stating it's qualities.
 
Yes... I was lazy using the buzz word voltage swing without defining it. Yes. maximum voltage swing peak to peak without clipping is just one part of the equation. Skew rate and a host of other factors are just as important in how well an amplifier performs, and of course, while many headphone amplifiers operate in voltage domain, others work in the current domain. Do I know the Mojo is deficient?  No, I don't have objective measurements from the bench. On the other hand I perceived a sound quality improvement when a well performing dedicated headphone amp was between the Hugo and my headphones.
 
Full disclosure, I didn't try adding an external amplifier to the mix with the Mojo because this is not a way I plan to use the Mojo so it would be a pointless exercise. I felt safe talking about external amplifier because  Chord has said the the Mojo and Hugo share the same op-amps and topology so what I found with the Hugo should be true of the Mojo, Given the rave reviews about the amplifier in the Hugo  a couple of years ago, I was hoping that the Hugo might remove the need for a dedicated amplifier in my primary system. My conclusion was that I could be happy with just the Hugo, but that the dedicated amplifier took the SQ up a notch which was immediately noticeable to me.
 
I agree that euphony and accuracy are not the same.  I typically favor accuracy. You obviously prefer euphony. I think the Mojo has done a good job providing a nice balance. That's why I purchase one. I would prefer a bit more accuracy, but I don't get everything I want. You are right... there aren't perfect amplifiers, but there are a number that are very good add very little color. I think the Headamp GS-X mk2 and Schiit Ragnarok are fairly good when it comes to not coloring the sound. Other people will disagree with me I am sure.
 
I am glad that the amplifier in the Mojo is driving your HD800 and HE1k to your full satisfaction. To be clear, the Mojo is driving my HD800 to my satisfaction and I said that. I am really enjoying the Mojo.  I I can't think of anything at it's price point which I have preferred, either portable or desktop. That said, there are a number of integrated or  DAC / amp pairs I have listened to which surpass the Mojo. Of course they are 2x-10x the cost of the Mojo and only the Hugo was portable.
 
--Mark

 

[jamato8]

Thanks! How are the stacking ergonomics?

I would either use the silicon case on the DX80 so you don't have two metal surfaces together, not for fear of scratching but so it doesn't slip around and then use some bands. The Mojo is about half the size of the DX80 but the coax or optical meet up well as coax and optical on the DX80 are the same port, which is a big convenience. I also have the AK100, which works well but the DX80 sounds much better as a dap so I would prefer to have a good sounding stand alone dap and the mojo for a combination. 

 

[tomcourtenay]

I would either use the silicon case on the DX80 so you don't have two metal surfaces together, not for fear of scratching but so it doesn't slip around and then use some bands. The Mojo is about half the size of the DX80 but the coax or optical meet up well as coax and optical on the DX80 are the same port, which is a big convenience. I also have the AK100, which works well but the DX80 sounds much better as a dap so I would prefer to have a good sounding stand alone dap and the mojo for a combination. 

Which digital you prefer out of the mojo with the dx80? Im using the dx80 coax out of the mojo with a 3,5 regular cable and it sounds good, but i seem to prefer the mojo with usb to my macbook and audirvana...perhaps i have to try a good coax cable or with the optical out of the dx80....

 

[sling5s]

I guess I'm one of those who prefer harmonic distortion and euphonic presentation to help me feel the music and not just hear it. In the end, it's about enjoyment. No apologies. 

 

 

[Torq]

Not to gainsay someone but I am also utterly intolerant of hiss and the Mojo SE846 combination produces an absolutely black background. The only portable that equals the Mojo is Ray Samuels Lightning and Intruder for having a blackhole quiet background and trust me prog music as long as some songs are have a lot of very quiet passages for me to hear hiss.

This is interesting and puts me into a diagnostic mode of thinking ... 
 
I just tested, again, my three portable DAC/Amps with all the IEMs I have on hand.  I tested with and without sources connected, with and without sources playing (including a test .WAV file that is pure silence), tried all available inputs, and I get consistent results with each unit and IEM.
 
A little chart showing the results:
 

 
"CWV" means the level of hiss changed with the volume setting of the amplifier (all were tested down to their minimum volume settings). The letter following that, "L", "M" or "H" indicates what gain setting was necessary in order to hear the hiss.  In other words, I hear hiss on the RSA Intruder even on low gain and it varies with the volume setting (higher volume, louder hiss) - though for the ER-4S, for example, I heard no hiss at all until I was on medium gain.
 
So, without wishing to come across as a smart-arse nor wanting to be argumentative, obviously our results here differ.  There are a limited number of possibilities for why:
 
1. My RSA Intruder and Mojo are both faulty.
2. My IEMs are almost all faulty.
3. My hearing is damaged and I hear hissing when there is none.
4. There's hiss present and my hearing is sensitive enough to pick it up and yours isn't.
 
It seems unlikely that both my Intruder and Mojo are faulty, though it's certainly possible (but see below).  It seems less likely that all my IEMs are faulty but again, I suppose, it's possible.  If my hearing was damaged in such a manner then I would expect to hear similar hiss with or without the amplifiers being powered and consistently with all of them; I don't (nor do I hear any hiss with these units driving my full-size cans).
 
If my Intruder is faulty then so are the two others I've heard (I've not heard the Lightning).  And I was interested to test because I've always seen in reviews of this unit that it is absolutely silent with IEMs and so far the three units I've heard aren't.  I wouldn't describe them as noisy either ... they're very quiet indeed - but I'm not going to say they're silent.
 
The hiss, in all of these cases, is very low-level (lowest on the Mojo, an obviously so) ... if it wasn't I'd not have kept the units, but it's definitely present in my testing.

 

[spook76]

This is interesting and puts me into a diagnostic mode of thinking ... 

I just tested, again, my three portable DAC/Amps with all the IEMs I have on hand.  I tested with and without sources connected, with and without sources playing (including a test .WAV file that is pure silence), tried all available inputs, and I get consistent results with each unit and IEM.

A little chart showing the results:




"CWV" means the level of hiss changed with the volume setting of the amplifier (all were tested down to their minimum volume settings). The letter following that, "L", "M" or "H" indicates what gain setting was necessary in order to hear the hiss.  In other words, I hear hiss on the RSA Intruder even on low gain and it varies with the volume setting (higher volume, louder hiss) - though for the ER-4S, for example, I heard no hiss at all until I was on medium gain.

So, without wishing to come across as a smart-arse nor wanting to be argumentative, obviously our results here differ.  There are a limited number of possibilities for why:

1. My RSA Intruder and Mojo are both faulty.
2. My IEMs are almost all faulty.
3. My hearing is damaged and I hear hissing when there is none.
4. There's hiss present and my hearing is sensitive enough to pick it up and yours isn't.

It seems unlikely that both my Intruder and Mojo are faulty, though it's certainly possible (but see below).  It seems less likely that all my IEMs are faulty but again, I suppose, it's possible.  If my hearing was damaged in such a manner then I would expect to hear similar hiss with or without the amplifiers being powered and consistently with all of them; I don't (nor do I hear any hiss with these units driving my full-size cans).

If my Intruder is faulty then so are the two others I've heard (I've not heard the Lightning).  And I was interested to test because I've always seen in reviews of this unit that it is absolutely silent with IEMs and so far the three units I've heard aren't.  I wouldn't describe them as noisy either ... they're very quiet indeed - but I'm not going to say they're silent.

The hiss, in all of these cases, is very low-level (lowest on the Mojo, an obviously so) ... if it wasn't I'd not have kept the units, but it's definitely present in my testing.

That is troubling because I have just retested the Mojo, RSA Intruder, RSA Lightning and my old RSA Protector and all four are, to my ears, dead silient. Honestly, you are the first person I have ever read that heard a hiss on a RSA portable amp. Further, when I run either the Intruder or the Lightning as strictly amps I turn down the volume on my iPod Touch and turn the volume up at about 75% on the amps (low gain) so that the amp is carrying the load and again no hiss. Not being an ENT doctor, I will not comment on possible medical issues.

 

[jamato8]

  The hiss, in all of these cases, is very low-level (lowest on the Mojo, an obviously so) ... if it wasn't I'd not have kept the units, but it's definitely present in my testing.

 
Another scenario is that your cable used for the IEMs is picking up interference. This will often come across as hiss and can vary depending upon the source/amp. This is a fact and can happen. 

 

[uzi2]

@Torq
I would suggest that no.4 is the most accurate conclusion. Some people are sensitive to hiss and others much less so. The ER4S is the least likely to demonstrate any hiss as it is more like a full sized headphone in it's characteristics,having a low sensitivity and 100ohms. The Shure 846 is the IEM that is most often quoted by people posting about hiss in these forums.

 

[Torq]

That is troubling because I have just retested the Mojo, RSA Intruder, RSA Lightning and my old RSA Protector and all four are, to my ears, dead silient. Honestly, you are the first person I have ever read that heard a hiss on a RSA portable amp. Further, when I run either the Intruder or the Lightning as strictly amps I turn down the volume on my iPod Touch and turn the volume up at about 75% on the amps (low gain) so that the amp is carrying the load and again no hiss. Not being an ENT doctor, I will not comment on possible medical issues.

 
I find it troubling as well; as I said, everything I've read about the RSA amps indicates they have dead quiet backgrounds - yet in my testing my Intruder is clearly the least quiet of the three.  I still wouldn't call it noisy, nor do I see it as a problem, but it's not the quietest in this round up.
 
It didn't matter what source, connected or unconnected, I used for any of the amps, the results were the same.
 
 

   
Another scenario is that your cable used for the IEMs is picking up interference. This will often come across as hiss and can vary depending upon the source/amp. This is a fact and can happen. 

 
Certainly a possibility.
 
If it's useful, I used the stock SE cables for SE testing on the SE846, balanced ALO audio cables for the balanced outputs on the RSA and ALO.  Stock cables on all the Etymotics.
 
I would expect, however, that if the cables are picking up interference they'd do so equally with each amplifier unless the amplifier itself was the source of the interference as there were no other environmental issues ands my house is pretty secluded (200 meters as the crow flies to the next closest one).  Yes, I can see that a difference even in the output impedance of the amplifier could alter that.
 
I will say that the ALO amplifier chirps and makes other odd sounds if it's in the same room as my WiFi Access Point/Router - and if it was the cable alone then I'd expect the same thing from the other two amplifiers.
 
That the results at all follow the amplifiers so consistently, with other factors controlled for, strongly suggests the differences are due to the amplifiers themselves.
 
I could, for giggles, go drive out into the hills this afternoon, since all of this stuff is portable, and test there.

 

[jamato8]

   
I find it troubling as well; as I said, everything I've read about the RSA amps indicates they have dead quiet backgrounds - yet in my testing my Intruder is clearly the least quiet of the three.  I still wouldn't call it noisy, nor do I see it as a problem, but it's not the quietest in this round up.
 
It didn't matter what source, connected or unconnected, I used for any of the amps, the results were the same.
 
 
 
Certainly a possibility.
 
If it's useful, I used the stock SE cables for SE testing on the SE846, balanced ALO audio cables for the balanced outputs on the RSA and ALO.  Stock cables on all the Etymotics.
 
I would expect, however, that if the cables are picking up interference they'd do so equally with each amplifier unless the amplifier itself was the source of the interference as there were no other environmental issues ands my house is pretty secluded (200 meters as the crow flies to the next closest one).  Yes, I can see that a difference even in the output impedance of the amplifier could alter that.
 
I will say that the ALO amplifier chirps and makes other odd sounds if it's in the same room as my WiFi Access Point/Router - and if it was the cable alone then I'd expect the same thing from the other two amplifiers.
 
That the results at all follow the amplifiers so consistently, with other factors controlled for, strongly suggests the differences are due to the amplifiers themselves.
 
I could, for giggles, go drive out into the hills this afternoon, since all of this stuff is portable, and test there.

No the amp doesn't have to be the source. It can be the cable and the amp is not equipped to deal with the interference. If you have different cables for the same IEM you can test this out. Twisted, vs braided vs straight. I realize not everyone has a variety of cables but I have heard it and it is the cable not the amp but an amp or dap or amp/dac can get rid of the interference, depending upon the circuitry. 

 

[griff2]

 
I do not buy this all. You need to bear in mind several facts:
 
1. The battery is capable of delivering 3A of current, and has very low impedance.
2. Mojo amplifier has a very high power supply rejection ratio.
3. The output is pure class A at 5v RMS into 300 ohm.
4. Reducing the output load only starts to increase distortion with 33 ohms - at this level it is very much lower than other headphone amps. The HD25 is a very easy 70 ohms.
5. Mojo is designed to drive loudspeakers. You will be amazed hearing it fill the room with beautiful sound using efficient 8 ohm horn loudspeakers.
 
Some people like the sound of more distortion - 2nd harmonic fattens the sound making everything sound phat, soft and rounded. But its not natural, nor do I find it musical, as everything sounds phat. I want soft sounds to sound soft, and sharp sounds to sound sharp - not everything to have a soft sheen on things all the time.
 
I can give you another example. I just had an email today from a very experienced dealer that asked me this question:
 
"Chord Mojo should have single amplification which drive to both headphone output, but if I'm using any headphones (HD800 for example, very heavy to drive) to put on headphone output 1 and I connect another headphone to headphone output 2 (Beyer T1 for example), I hear no differences on sound quality. Normally if one amplification section used to drive 2 headphones output, then once we connect the second headphone will make overall sound quality degradation (as the case of Beyerdynamic A20 amp, Grace Design M903, etc). What is the logical explanation of this? As it seems Mojo has 2 separate amplification sections which drive independently for each headphone output."
 
Of course Mojo does not have two amplification stages. It can drive two headphones with ease because it has exceptional low output impedance, and it has exceptional current linearity. So loading it with more headphones has no effect, unlike other headphone amplifiers.
 
Indeed, when I initially started designing Hugo I was shocked how poor from a measurement point of view headphone amps were. Poor output impedance, huge levels of distortion, and poor current linearity seem to be typical. And these things matter, if your goal is transparency and musicality. 
 
Rob

Thanks for the info, this is interesting information and has given me something to think about.

 

[Sound Eq]

why no comparisons between ifi micro dsd and mojo
 
as i am seriously waiting for a comparison for quite sometime
 
please whoever has both can you compare both and how do u think they would match lcd2 rev2

 

[Torq]

 
No the amp doesn't have to be the source. It can be the cable and the amp is not equipped to deal with the interference. If you have different cables for the same IEM you can test this out. Twisted, vs braided vs straight. I realize not everyone has a variety of cables but I have heard it and it is the cable not the amp but an amp or dap or amp/dac can get rid of the interference, depending upon the circuitry. 

I have SE and Balanced cables for the SE846.
 
Using both the RSA Intruder and the ALO (since the Mojo has no balanced connections), I see the exact same results with either cable into the SE846.  Both have hiss with both cables.  The magnitude of that hiss does not change between cables.  And, while I have no issue believing that the simple SE cable is acting as an antenna I have a much harder time ascribing such behavior to a balanced connection.

 

[salla45]

  So what's everyone's favorite IEM to use with the Mojo. I'm thinking of upgrading my IEMs.

K3003's sound super