Chord Mojo DAC-amp ☆★►FAQ in 3rd post!◄★☆
Jan 2, 2016 at 10:47 AM Post #8,251 of 42,391

shigzeo

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Correct. Digital either works or it doesn't. You won't for example get better sq from USB over coaxial.
If you want to utilise the dap's DAC, then listen via line out to the mojo.


Again, unless your USB, like the one on my iMac's, has a mind of its own.
 
Jan 2, 2016 at 11:35 AM Post #8,253 of 42,391

NaiveSound

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If Usb misbehaves, you could use spdf, couldn't you? As far as I know all iMacs have optical out, and from what I read here - USB and Optical inputs are pretty much equal when it comes to Mojo.


Am I maximizing my Mojos potential with this wiring? And set up?

 
Jan 2, 2016 at 11:49 AM Post #8,254 of 42,391

Mython

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If Usb misbehaves, you could use spdf, couldn't you? As far as I know all iMacs have optical out, and from what I read here - USB and Optical inputs are pretty much equal when it comes to Mojo.


Am I maximizing my Mojos potential with this wiring? And set up?


 
 
Difficult to tell, from your photograph, whether that is plaited wire or co-axially braided. If it is co-axially-braided, then yes, that's about as good as one could reasonably hope for (75 ohms is generally considered the best specification, but it's not absolutely critical).
 
You have a pretty decent setup there.
 
The comments about USB vs Optical were aimed at the reliability of the outputs of the iMac, rather than the reliability of the inputs of the Mojo.
 
Jan 2, 2016 at 11:54 AM Post #8,256 of 42,391

Mython

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Do you guys think the mojo is too revealing ?
Bad ones turn worst and good ones become perfect
smily_headphones1.gif

 
 
Just like a high quality camera lens!
 
Some people have spots, wrinkles, warts, cuts, grazes, bruises....   so does that mean it is best to always use a poor quality lens that doesn't focus well? 
etysmile.gif
 
 
Jan 2, 2016 at 12:04 PM Post #8,257 of 42,391

AndrewH13

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Do you guys think the mojo is too revealing ?
Bad ones turn worst and good ones become perfect :)


No one would buy Mojo if they didn't want to hear it as it is would they?
 
Jan 2, 2016 at 12:10 PM Post #8,258 of 42,391

jonnymooshoo

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What effect does a high quality transport cable have if the mojo is doing all the audio processing and amplification?
 
Jan 2, 2016 at 12:19 PM Post #8,260 of 42,391

Mython

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What effect does a high quality transport cable have if the mojo is doing all the audio processing and amplification?

 
 
Negligible, unless you have a lot of stray RF from a smartphone, adjacent to the Mojo, in which case, some cables might perform better than others.
 
 
   
In the 1980's, people started talking about mains cables making a difference to the sound quality - and I didn't believe it either - particularly as my pre-amp had 300 dB of PSU rejection in the power supply. But I did a listening test, and yes I could hear a difference. Frankly I still could not believe the evidence of my own ears, so did a blind listening test with my girl friend. She reported exactly the same observation - mains cables did make a difference to SQ.
 
To cut a long story short, I proved the problem was down to RF noise. RF noise inter-modulates with the wanted audio signal within the analogue electronics, and if the RF noise is random, then the distortion is random too and you get a increase in noise floor with signal. This increase in noise floor is noise floor modulation, and the brain is very sensitive to it; you can perceive tiny amounts of noise floor modulation as a brightening or hardening of the sound. By tiny I mean the noise floor modulation needs to be well below -200 dB, so the brain is very sensitive to it. With the right test equipment, you (APX5555 is only test equipment that has no innate noise floor modulation) can easily measure the effect.
 

The RF characteristics of the cable can change the RF noise that gets injected into Mojo's ground plane, and this is the mechanism for changes in smoothness. You may say why can't you make it insensitive to it; well I go to silly lengths to RF filter and decouple, and use dual solid ground planes on the PCB, but you can't remove the problem. For Dave, Hugo TT and 2 Qute I have galvanic isolation, and this eliminates the problem (along with other SQ problems such as sound-stage depth). But I can't do this with portable devices, as it draws power from the 'phone. That said it's less of an issue with portable electronics as they are less power hungry and create less noise.

 

So what are the best USB cables? Firstly, be careful. A lot of audiophile USB cables actually increase RF noise and make it sound brighter, and superficially impressive - but this is just distortion brightening things up. Go for USB cables that have ferrites in the cable is a good idea - it may also solve any RF issues from the mobile that you may have too.

 

Rob

 
Jan 2, 2016 at 12:21 PM Post #8,261 of 42,391

Mython

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Jan 2, 2016 at 1:07 PM Post #8,262 of 42,391

Ike1985

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Cheers! Dirt Wolf is a great DIPA.

Also like Chill Wave from your list.

A few of my favorite IPAs this year:
Palate Shifter
The Taste of Hops to Come
Seeking Alpha
Hercules


Since it appears we have similar tastes, I'm noting these and keeping an eye out. : P
 
Jan 2, 2016 at 1:10 PM Post #8,263 of 42,391

Whitigir

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Negligible, unless you have a lot of stray RF from a smartphone, adjacent to the Mojo, in which case, some cables might perform better than others.


Agreed, even with different sources feeding the Mojo, I was unable to hear differences. Maybe different apps that were used to play the music, but other than that :D...?
 
Jan 2, 2016 at 1:14 PM Post #8,264 of 42,391

Ike1985

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Do you guys think the mojo is too revealing ?
Bad ones turn worst and good ones become perfect :)


I do MP3 128 streaming and listen to a lot of metal bands that can't afford nice studios and while the mojo has incredible resolution-it maintains the musicality, as I've said before. It all sounds good to me.
 
Jan 2, 2016 at 1:15 PM Post #8,265 of 42,391

NaiveSound

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Difficult to tell, from your photograph, whether that is plaited wire or co-axially braided. If it is co-axially-braided, then yes, that's about as good as one could reasonably hope for (75 ohms is generally considered the best specification, but it's not absolutely critical).

You have a pretty decent setup there.

The comments about USB vs Optical were aimed at the reliability of the outputs of the iMac, rather than the reliability of the inputs of the Mojo.


Just a l17 cable
 

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