Chord Mojo(1) DAC-amp ☆★►FAQ in 3rd post!◄★☆
Sep 26, 2016 at 11:03 PM Post #23,282 of 42,765
Does the mojo DAC offer native support for android phone via otg. By native, I mean using any application,  not just within USD audio player pro.  
I'm planning to use it with my lg g3. 
And does it have a totally black background? 
Its not an issue with the Mojo. The question will the phone be able and do you have the right otg cable.
 
Sep 26, 2016 at 11:25 PM Post #23,283 of 42,765
  Does the mojo DAC offer native support for android phone via otg. By native, I mean using any application,  not just within USD audio player pro.  
I'm planning to use it with my lg g3. 
And does it have a totally black background? 

I have tried 3 phones; Oneplus one, Meizu MX4 pro, Xiaomi Note pro, using Onkyo app with the DSD files.
Only Oneplus one that the light on Mojo shows white color, which means it can send DSD out.
 
Sep 26, 2016 at 11:40 PM Post #23,284 of 42,765
 
  Does the mojo DAC offer native support for android phone via otg. By native, I mean using any application,  not just within USD audio player pro.  
I'm planning to use it with my lg g3. 
And does it have a totally black background? 

I have tried 3 phones; Oneplus one, Meizu MX4 pro, Xiaomi Note pro, using Onkyo app with the DSD files.
Only Oneplus one that the light on Mojo shows white color, which means it can send DSD out.

You have Onkyo pro version on all three mobiles ?
 
Sep 26, 2016 at 11:53 PM Post #23,286 of 42,765
   
Lyr 2's sound signature is bright neutral so no matter what DAC you feed it, it will sound that way. You lose the Mojo's warm signature by feeding it to an amplifier. Plugging in a headphone straight to the Mojo allows the listeners to hear the Mojo's tuning which is supposed to be warm and relaxed. Even if you feed the Mojo to the supposedly one of the most transparent amps such as the Headamp GSX MK2, you will lose the warmth that Mojo is supposed to sound to the listener. Regarding the power output, if Mojo isn't able to drive the headphones properly, the headphones will sound "lazy" and lacking PRAT. If there's no PRAT difference between Lyr 2 and Mojo other than the brighter tonality of Lyr 2, that means that the Mojo is capable of driving the HE 560 properly IMO.

 
 
I just did some more comparisons between the Mojo and Lyr 2 with Mojo as the DAC and found the Lyr 2 has a very slight mid bass punch that the Mojo doesn't have. Also the separation on high hats and cymbals is better on the Lyr 2 which might translate to brightness but it's not sibilant by any means. If anything it's further extension above 16Khz that gives it more air than the Mojo.
 
The differences are microscopic and you really have to listen very very hard to hear any differences. 
 
I can agree that the Mojo is more than powerful enough but the Lyr 2 with these Amperex 7308 tubes just makes planar magnetics sing. The Lyr 2 is a tad harsh with my TH900's though compared to the Mojo which has a meatier and more tamed sound on the upper mids which I'm sensitive to.
 
Sep 26, 2016 at 11:56 PM Post #23,287 of 42,765
 
  Over the summer, I found the Mojo way too unreliable to use as a desktop DAC. If it was charging and playing at once, it'd shut down far too often due to heat. It actually annoyed me enough that I bought a Modi Multibit as my desktop DAC. The Mojo hardly ever gets to be the desktop DAC now, it's mostly on mobile and travel duty. The upside is that I don't need to mess with replugging stuff when I get home any more.

 
 
Not to downplay the legitimacy of your irritation, but did you try turning Mojo on its edge? This makes a substantial difference to the efficiency of thermal radiation.

 
If you fully charge Mojo then use it in a desktop it will not switch off; the power dissipation that the charger uses in matching the current drawn by Mojo is negligible. You are only at risk when charging and using at red - and indeed as Mython says putting Mojo on its side will solve that issue too.
 
Just to give you some numbers - fully charged and matching Mojo's current draw the power dissipation is 107 mW for the charger circuit. That will increase running temperature by less than 1 deg C. But at flashing red it is 910 mW for the power dissipation in the charger.
 
Now I could fix this by using a switcher based charger rather than a linear one - but these inject too much RF noise onto the battery. This would impair sound quality, and Mojo's design goals was that plugging in the charger would have no significant change in SQ - which would not happen if I used a switcher based charger. I am not prepared to damage SQ as to me this is the most important aspect just for a tiny improvement in usability.
 
Rob
 
Sep 27, 2016 at 12:04 AM Post #23,288 of 42,765
 
Again, I'm not irrationally defending Mojo - I'm just saying life isn't perfect, Mojo is substantially pushing the boundaries of music processing capability, and doing so in a tiny pocket format, and every electronic device on planet earth has some compromises and vulnerabilities, so a little perspective is not an unreasonable thing to expect. If one doesn't like the compromises involved with one electronic device, that's their prerogative, as long as one gives a nod of acknowledgment to the technical challenges associated with them, and doesn't compare apples with oranges
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beerchug.gif

 
Yes, stuff is hard, nor will you find me pretending otherwise. However, like I say, it's a really good job that neither this nor the GOV2 are mass market devices, or there would be hell to pay for their flaws. We persevere in pursuit of the sound because we must, however it's as well to do so with your eyes open.
 
I'm very in favour of recognising and detailing them honestly though, as the prevalent "everything is awesome" narrative is misleading and unhelpful. People who are having problems should be able to enumerate and discuss them without being buried under a fanboy smokescreen. I think you provided an excellent example- some people may never have thought of balancing the Mojo on its edge to stop it overheating. Being well-informed increases the chances of being able get the most from it.
 
I am aware that the Mojo uses one of the smaller Xilinx FPGAs in a portable device, and while my FPGA-fu is rusty these days, I get it.That's why I bought it 
beerchug.gif
 


Isn't there a Kintex 7 in the Mojo? Maybe it's a smaller part in the family, but it's also Xilinx's latest generation of parts. These are not small by any measure... It's remarkable the resources they're packing into these things... Particularly DSP48 slices and BRAMs which are useful for these types of signal processing applications. And they're able to run the parts at higher clock rates and lower power than previous generations. Plus the new Vivado tool is a complete overhaul of the old ISE design suite... Synthesis tool is a bit smarter, but PAR does an infinitely better job of closing out timing.

Also, any chance we could stop with the marketing cliches? The 44 DSP cores are what, individual modules in the RTL hierarchy? Are these meaningful modules or do they include things like synchronizers for clock domain crossings too (assuming there are any, just an example)? 26,000 taps is for one filter? Or the number of taps in all the filters combined? Are we talking about a giant polyphase FIR or a number of filter stages in different parts of the processing chain? What is the point of interpolating up to 200+MHz? Surely the DAC is not capable of running at that rate... And if it is, why?

Sent from my E5803 using a highly trained, special forces carrier pigeon
 
Sep 27, 2016 at 12:09 AM Post #23,289 of 42,765
I'm surprised nobody has come up with a vertical stand for the Mojo yet.
 
Sep 27, 2016 at 12:15 AM Post #23,291 of 42,765
  I'm surprised nobody has come up with a vertical stand for the Mojo yet.

 
I bought the leather case for my Mojo just so I could bedazzle mine. Jk!
 
Seriously tho, I didn't mean to get everyone off tracking and arguing. I personally have a love affair with my Lyr 2 and Amperex tubes. I replaced my Hugo with the Mojo as a DAC for it. I found the Hugo to be sterile and detail oriented to pair with the Lyr 2 with certain headphones namely the TH900 which is already prone to sibilance in the upper mids.
 
The Mojo isn't as bright as the Hugo and the Lyr 2 kind of amplifies the meaty sound and adding some sparkle up top which I happen to adore. 
 
The Mojo by itself is a freaking insane unit and if I had nothing else I would be silly to look elsewhere. But unfortunately, I've heard both and prefer my current stack with Mojo feeding the Lyr 2. It might sound horrible to some but to me its awesome. 
 
I'm only talking 1 type of cans which are ortho's. My TH900's sound better on the Mojo by itself as the amp instead of the Lyr 2. My ears are weird so take what I'm saying with a grain of salt.
 
Sep 27, 2016 at 12:18 AM Post #23,292 of 42,765
but won't all otg and otg supported phone function the same?  
There is the new c type usb. I demoed a few phones and many phones had different usb connections that wouldnt connect the mojo.
 
Sep 27, 2016 at 12:30 AM Post #23,294 of 42,765
don't they make USB type C adapters to work with Micro USB?
Yes big adapters. As if now makes it difficult to take the Mojo on the go. Right now in HK to connect the Mojo to the Cayin i5 Android Dap it requiers a big adapter. Only a few shops have.
 

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