Chord Mojo DAC-amp ☆★►FAQ in 3rd post!◄★☆
Apr 15, 2016 at 1:30 AM Post #16,007 of 42,205

Rob Watts

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  Hello Rob,
 
If 2 micro usb otg cable have exact same RF noise, then can we assume that the SQ will be same for both OTG cables ?

 
Yes in principal it would. But RF noise is a pesky thing - it's like a fungal infection, impossible to get rid off completely. When I designed a RF noise mains filter I had to filter from 100 kHz to well over 1 GHz. At 1 GHz very odd things can happen with RF, so no differently designed cable is identical, so do not be surprised if they sound different. The warmer and smoother sounding one is technically better. It will also very much depend upon the source too, which is where the bulk of the RF noise is coming from.
 
Rob  
 
Apr 15, 2016 at 1:35 AM Post #16,008 of 42,205

masterpfa

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  Before I take my Mojo back to the dealer for them to check out, has anyone experienced an issue where the USB input suddenly stops working? It was working earlier, then had to unplug my iPhone to go to a meeting and by the time I came back and plugged in again, the phone would not detect the Mojo. The power light on the Mojo shows red. I went home and plugged it into my computer which was working fine with the Mojo the night before and same issue where it doesn't detect the Mojo.
 
I've tried rebooting the iPhone and computer, turned on/off the Mojo, and changing cables. Any thoughts?

A silly suggestion, are you connecting to the Data USB and not the Charging port

I've heard some people have done that before (Who me? Never, well not more that 3 times 
redface.gif
)

Has your Mojo gone down fully and run flat?

EDIT: The bit about the correct port was a joke by the way.
 
Apr 15, 2016 at 1:37 AM Post #16,009 of 42,205

felix3650

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I think they do it because it gives the illusion that it sounds better... Us audiophile type music experts know better. :wink:


Because the geniouses at Google think that every USB DAC connected through an OTG cable should play at its max bit-depth and resolution, up to a maximum of 24/192. They don't bother writing a simple kernel driver who "fixes" this like UAPP developer did :/

Do you mean Samsung are preventing people from installing UAPP etc. to circumvent Androids native upsampling?


He meant that with UAPP you can only access local files stored on the phone/microSD memory and stream from Tidal. The rest of the apps like the default audio player, youtube and any other media player (even the official Tidal app itself) will play through the Android audio kernel, thus get upsampled once the music reaches the DAC. I have a friend with a Galaxy S7 and UAPP works perfectly on his phone and my S5 too. No chance from Samsung to lock this out :wink:

I was hoping for a 10cm Type-C to micro USB OTG, but I suppose that will have to do.


There is an USB-C to micro-USB adapter from Xiaomi which can be of help. This way you can use your existing cables. Also it's pretty cheap :)

http://m.geekbuying.com/item/Original-Xiaomi-Usb-C-Adapter-USB-Type-C-To-Micro-USB-Adapter-for-Google-Nexus-6P-Nexus-5X-Xiaomi-Mi4c-OnePlus-Two-Sony-Z5-Lenovo-Zuk-Z1-Meizu-Pro-5-Xiaomi-Mi4s-Xiaomi-Mi5-355450.html

​Actually it's ATT and one other company will not let you root some android devices, maybe others.  I tried to root my note 4 through ATT, went to the root page, and right there in black and white it says ATT and one other company won't let you root.  Definitely switching in a few months when the contract runs out.!


They don't officially let you root it (the same for any other big name manufacturers).
Your only option for now is to keep checking the ATT Note 4 thread over at XDA forum. I read that something is in the works..
 
Apr 15, 2016 at 1:43 AM Post #16,010 of 42,205

music4mhell

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  Hello Rob,
 
If 2 micro usb otg cable have exact same RF noise, then can we assume that the SQ will be same for both OTG cables ?

 
Yes in principal it would. But RF noise is a pesky thing - it's like a fungal infection, impossible to get rid off completely. When I designed a RF noise mains filter I had to filter from 100 kHz to well over 1 GHz. At 1 GHz very odd things can happen with RF, so no differently designed cable is identical, so do not be surprised if they sound different. The warmer and smoother sounding one is technically better. It will also very much depend upon the source too, which is where the bulk of the RF noise is coming from.
 
Rob  

Thanks for the reply, now my basics are clear :)
 
Apr 15, 2016 at 1:45 AM Post #16,011 of 42,205

Kermy

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  A silly suggestion, are you connecting to the Data USB and not the Charging port

I've heard some people have done that before (Who me? Never, well not more that 3 times 
redface.gif
)

Has your Mojo gone down fully and run flat?

EDIT: The bit about the correct port was a joke by the way.

 
Yep checked the port multiple times to be sure.
biggrin.gif

 
Battery-wise, it's never gone all the way down to the point where it shuts off and doesn't come on. Right now the battery indicator light shows purple when plugged in. I have it charging on a 2.1A charger. Going to see what happens over night.
 
Apr 15, 2016 at 2:30 AM Post #16,012 of 42,205

rrollens

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Could use some help. Just received my Mojo today. Charged it up, and while using the Coax Input on the Mojo to either my Questyle DAP or my Onkyo DAP using their Line Out, not getting any sound from the Mojo. What cable should I be using? Is the proper cable the 3.5mm mono cable, or the 3.5mm stereo cable? Help much appreciated. 
 
Apr 15, 2016 at 2:31 AM Post #16,013 of 42,205

masterpfa

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Yep checked the port multiple times to be sure.
biggrin.gif

 
Battery-wise, it's never gone all the way down to the point where it shuts off and doesn't come on. Right now the battery indicator light shows purple when plugged in. I have it charging on a 2.1A charger. Going to see what happens over night.

Volume buttons, silly I know but I have had them set too low before as well
 
 
Apr 15, 2016 at 3:39 AM Post #16,014 of 42,205

YugiRider2

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If I got a 3.5mm to 2x 3-pin XLR and connected the Mojo to a fully balanced amplifier through line out, would it be "balanced"? Or would it just be useless considering that the Mojo is not balanced?
Sorry if this is a stupid question.
 
Apr 15, 2016 at 3:45 AM Post #16,015 of 42,205

x RELIC x

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Could use some help. Just received my Mojo today. Charged it up, and while using the Coax Input on the Mojo to either my Questyle DAP or my Onkyo DAP using their Line Out, not getting any sound from the Mojo. What cable should I be using? Is the proper cable the 3.5mm mono cable, or the 3.5mm stereo cable? Help much appreciated. 


The Questyle QP1R uses optical, not coaxial so you need a 3.5mm mini optical to TOSlink optical cable to connect to the Mojo.

The DP-X1 does not have a coaxial output and the Mojo does not take an analogue input from a line-out jack. You need to use a USB OTG cable to connect to the Mojo from the DP-X1.
 
Apr 15, 2016 at 5:59 AM Post #16,016 of 42,205

GreenBow

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  If I got a 3.5mm to 2x 3-pin XLR and connected the Mojo to a fully balanced amplifier through line out, would it be "balanced"? Or would it just be useless considering that the Mojo is not balanced?
Sorry if this is a stupid question.

 
I think the balanced effect is lost because the Mojo output is not balanced. However I would recommend search the thread and the third post, for discussion on 'balanced'. I believe the conclusion was do not worry if you can not run balanced.
 
Apr 15, 2016 at 6:17 AM Post #16,017 of 42,205

x RELIC x

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If I got a 3.5mm to 2x 3-pin XLR and connected the Mojo to a fully balanced amplifier through line out, would it be "balanced"? Or would it just be useless considering that the Mojo is not balanced?
Sorry if this is a stupid question.


Changing the output to 2x 3-pin XLR cables will not in any way make the Mojo balanced.

If the amplifier you are connecting to has a phase splitter on the single ended Input like the Cavalli Liquid Carbon, then it could be handled as a balanced signal inside the external amplifier's balanced circuitry to a balanced headphone output. Balanced output is not necessarily an improvement in transparency with a well designed single ended output and is completely unnecessary in the Mojo's design. Actually because of the performance of the Mojo's DAC a single ended discrete output is in fact better than a balanced design for transparency. As GreenBow mentioned there is a lot of information from Rob Watts regarding balanced output in the third post.
 
Apr 15, 2016 at 6:49 AM Post #16,018 of 42,205

headmanPL

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I
  Anyone tried mojo with Grado 325e?  Im thinking about trying open cans again now i have this


I have them. They sound fantastic. Of course they leak sound, but I find them to be an amazing partnership.
Interestingly, in comparison to the Grado's, I find other HP's and IEMs to be less 3 dimensional. The Grado's with Mojo sound less like an inside the head source. The illusion is that the sound is coming from in front of me, like a loudspeaker. Going back to other HP's is a surprise as they don't project forward in the same way.
 
Apr 15, 2016 at 7:40 AM Post #16,019 of 42,205

jmills8

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Apr 15, 2016 at 8:01 AM Post #16,020 of 42,205

Ike1985

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Do you mean Samsung are preventing people from installing UAPP etc. to circumvent Androids native upsampling?

 
No, I just mean that everything not sent through UAPP will be upsampled.
 

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