Chord Mojo DAC-amp ☆★►FAQ in 3rd post!◄★☆
Dec 30, 2016 at 7:08 AM Post #28,006 of 41,658

GRUMPYOLDGUY

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Thank you for trying. It says:
tail: cannot open 'var/log/messages' for - reading: No such file or directory.
tail: no file remaining

Then when I plug Mojo in, there is no message.


I think this netbook's OS is actually a cut down version of Linux. I know the netbook XP version was. It would be easier to install netbook XP, and I have licence for it. However it's only a 4GB SSD, so too short on OS space for XP I guess. I could buy a bigger SSD on ebay I guess. However I might just be better getting a tablet. Shame though as this netbook is silent and would be perfect.

The OS is called EEEPC version 1.0.6.6. I think it says Linux on the install disks. (I will check.) 


That's fine, you'll have to do it the old fashioned way... Use this command before and after plugging in and turning on Mojo:

dmesg

You'll see several new lines after turning on Mojo. Please report those lines here.
 
Dec 30, 2016 at 7:33 AM Post #28,008 of 41,658

jmills8

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Is anyone using the Mojo *without* an amp with HD800?
I need a DAC/amp, budget 500$, for HD800, but worried Mojos' amp is not powerful enough for it.
what style of music will you listen to?
 
Dec 30, 2016 at 7:51 AM Post #28,009 of 41,658

GreenBow

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Thank you for trying. It says:
tail: cannot open 'var/log/messages' for - reading: No such file or directory.
tail: no file remaining

Then when I plug Mojo in, there is no message.


I think this netbook's OS is actually a cut down version of Linux. I know the netbook XP version was. It would be easier to install netbook XP, and I have licence for it. However it's only a 4GB SSD, so too short on OS space for XP I guess. I could buy a bigger SSD on ebay I guess. However I might just be better getting a tablet. Shame though as this netbook is silent and would be perfect.

The OS is called EEEPC version 1.0.6.6. I think it says Linux on the install disks. (I will check.) 


That's fine, you'll have to do it the old fashioned way... Use this command before and after plugging in and turning on Mojo:

dmesg

You'll see several new lines after turning on Mojo. Please report those lines here.

 
I can only se what lines the screen will allow. I can not work out how to scroll back up the page. If I press arrow keys it just puts up the last text entered by the prompt.
 
Anyway there was too much text to type out. I got a picture. Sorry it's not a clear photo as I could not use flash.
 

 
Dec 30, 2016 at 8:13 AM Post #28,010 of 41,658

JaZZ

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  I'm using EQ to alter my musica, is it some kind of heresy using Mojo + EQ since using EQ would negate all the efforts of keeping the signal as clean as possible? 
biggrin.gif

 
Hi George
 
Digital equalizers shouldn't add any harmonic distortion, so won't compromize transparency in any way (per se). Quite the opposite: If you manage to linearize the amplitude response of your headphones via equalizing, you may even increase the perceived transparency in that you prevent dominating frequency bands from masking underrepresented ones. Of course it's possible that your preferred tonal balance does exactly the opposite, but that's in the nature of colorations and not a technical issue.
 
In any event, you don't have to care. Virtually every recording has undergone one or more EQ and other DSP (I'd say fortunately so). See it that way: Even using a different guitar pickup or different strings for a recording is sort of equalizing. Music should be allowed to sound as it sounds or is intended to sound. And the listener is entitled to use his or her playback equipment the way he or she likes best (not everybody is a purist). The only caveat is that there are better and worse methods. So reamplifying the Mojo's output signal is a bad idea if you like maximum transparency and preserved subtleties. Most likely you'd get even higher listening pleasure by enhancing the sound with adequate equalizing instead of adding euphonic distortion. Moreover euphonic distortion could be added by some audio-player plugins – for free and with much greater flexibility.
 
Dec 30, 2016 at 8:53 AM Post #28,013 of 41,658

GRUMPYOLDGUY

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I can only se what lines the screen will allow. I can not work out how to scroll back up the page. If I press arrow keys it just puts up the last text entered by the prompt.

Anyway there was too much text to type out. I got a picture. Sorry it's not a clear photo as I could not use flash.




That's fine. In the future you can pipe to less to be able to scroll, basically vi controls:

dmesg | less

Then :q when you're done.

Looks like the audio driver is failing to initialize the device correctly. Could be a number of reasons for that. Can you do a 'uname -r'?
 
Dec 30, 2016 at 9:22 AM Post #28,014 of 41,658

Takeanidea

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Is anyone using the Mojo *without* an amp with HD800?
I need a DAC/amp, budget 500$, for HD800, but worried Mojos' amp is not powerful enough for it.


The Mojo doesn't need an amp for the HD800. I'm an owner and user of both for well over a year. The HD800 sounds incredible through it. 
 
Dec 30, 2016 at 10:57 AM Post #28,016 of 41,658

maczrool

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  Nope.  No sound with any of the DSD: ASIO options or the Chord WASAPI push or event options while set to output DSD.  Switching over to PCM it continues to work great.  I'm beginning to think maybe something is wrong with mine.  I will try Jriver but just to rule that out.  Thanks though!

I got it working in JRiver with WASAPI first and then in foobar using the Output: "DSD : WASAPI (push) (Chord Async USB 44.1kHz-768kHz)" and Tools, SACD set to output mode "DSD+PCM".  This is definitely not how others have documented it should be set up so I'm not sure why it's necessary to set it up this way but the power ball lights up white and I get great sound.
 
Dec 30, 2016 at 11:13 AM Post #28,017 of 41,658

Takeanidea

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  if connected via optical through my imac does the mojo treat the incoming audio signal with the same integrity as if the signal was routed through the asynchrous usb input.ie clocking? people are saying better sound through optical but I feel it is important to understand this point. only 7 days left!!!

 
 
  i just read on here that mojo experiences distortion through usb computer link due to not being galvanically isolated. is this really true??

 
 
Yes, it's true and the measurements show it.
 

Hi guys, I have done 2 recordings. The only thing I changed was the cable. Recording 1 - optical.  Recording 2 - USB. Both cables were from the Mojo accessory box so cheap and cheerful ones. The line out from the Mojo was fed to an ART USB Analogue to Digital Device and recorded into Audacity at 44.1 sampling. 
My purpose was to see whether there is a difference in the SQ of Optical v USB. There are many more tests that could be done , i.e with Jitterbug(don't have one) a USB hub(have one of those) a better quality USB and Optical cable(nope don't own currently) mains cable plugged into the Laptop, Mojo being charged at the same time; the possibilities are many. This seemed the simplest test. The results are available on my Google Drive and I would welcome your thoughts
 
Dec 30, 2016 at 11:22 AM Post #28,018 of 41,658

GRUMPYOLDGUY

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Hi guys, I have done 2 recordings. The only thing I changed was the cable. Recording 1 - optical.  Recording 2 - USB. Both cables were from the Mojo accessory box so cheap and cheerful ones. The line out from the Mojo was fed to an ART USB Analogue to Digital Device and recorded into Audacity at 44.1 sampling. 
My purpose was to see whether there is a difference in the SQ of Optical v USB. There are many more tests that could be done , i.e with Jitterbug(don't have one) a USB hub(have one of those) a better quality USB and Optical cable(nope don't own currently) mains cable plugged into the Laptop, Mojo being charged at the same time; the possibilities are many. This seemed the simplest test. The results are available on my Google Drive and I would welcome your thoughts


I'm not a fan of downloading files distributed through forums this way. No offense, but you never know who you can trust.

Can you please import them into matlab or octave and plot the spectrum? Then share the images here.
 
Dec 30, 2016 at 12:04 PM Post #28,020 of 41,658

music4mhell

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Is anyone using the Mojo *without* an amp with HD800?

I need a DAC/amp, budget 500$, for HD800, but worried Mojos' amp is not powerful enough for it.



I am using it with LCD-4 no problems. You don't need an amp.
If you are talking about power only, then Mojo can drive lcd 4 or hd800.

but for better resolution, soundstage, separation, you need a good amp with mojo...IMHO
 

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