[Joe Bloggs]

Joe Bloggs, if you read my earlier impressions regarding x7 vs mojo (and assuming my impressions are fair - which could be entirely bs) what is you take on why I am getting such a different experience with these two dacs?

I'll discuss your X7 impressions via pm to avoid derailing the thread, bavinck.

 

[Peter Hyatt]

   
I am not debating it, I just suggested it as an option.
 
This notion of brain burn in is the biggest crock of !!!! I have ever heard IMO!!!

 
I suggest that you stop giving orders on this thread and leave it to the thread starter and moderators.

The brain burn, or becoming accustomed to the brain interpreting the data is the most fascinating part of this to me.  Sadly, the engineer measurements are lost on me. 
 
In the training I do, students do the work on paper.  Then it is done online.  It is all with words.  By the time they have studied for two years, the brain has become so accustomed to what they have been doing, that they are able to identify the words "on the fly", that is, live.  
 
It takes many many hours for proficiency, but once the brain pattern is instilled, they experience success. 

 

[betula]

I realize that this is a losing battle as the listener in question has made up his mind regarding what he's hearing with the X7 vs the mojo, but--
The only reason DACs need to upsample is to make room for an analogue reconstruction filter with a less steep rolloff than the brickwall filtering a non-oversampled digital sample stream would require. The filter would cut off at the Nyquist frequency of the oversampled sample stream, which is 16x (say) the original Nyquist frequency, leaving plenty of room for the signal to be passed without attenuation at the original Nyquist frequency.

16x upsampling is plenty enough for this--if that were all that the X7 were using. I'm not at liberty to fully disclose the workings of the ES9018S DAC the X7 uses, but what is publicly known is that it upsamples PCM and DSD alike into a high frequency multibit stream for subsequent ASRC jitter reduction, volume control and D/A conversion. Seeing as it does this upsampling for up to DSD512, in the case of 44.1kHz audio the upsampling factor would also be at least 512x.

But back to the central argument. Does a high oversampling factor increase "timing performance" of the reproduced signal? Quite frankly, no, it wouldn't, even if we pretended for the moment that the "timing performance" as a metric made any sense!

Your contention, apparently, is that the "timing performance" of the DAC is equivalent to the sampling period of the upsampled sample stream. At 16FS, sampling rate = 44.1kHz*2048 = 705.6kHz, sampling period = 1/(705.6x1000)s = 1.4μs as claimed.

The thing is, the D/A converter at the receiving end of this sample stream outputs ANALOG signals--and it does this by lowpassing the digital pulse train. An analogue lowpass filter does not dumbly "join the dots" of the digital sample stream--it has particular mathematical characteristics dictated by the fact that it preserves all frequencies in its passband and rejects all frequencies in its stopband. But a picture speaks a thousand words:


On the top, the D/A conversion of your upsampled signal as you would seem to have us believe is going on, wherein adding more points would smooth out the curve;
At the bottom, the D/A conversion of the upsampled signal as actually occurs--output is analog waveform that bears little resemblance to what an imagined "join the dots" curve would look like.

http://www.head-fi.org/t/769647/objectivists-board-room/1635#post_12203380

Elsewhere I detailed technical arguments regarding Rob's "timing" contentions, I have yet to receive a response.

---

Don't mind me, I'm just taking an early retirement from my position as FiiO rep

That graph is just the visualization of the smooth and liquid sound of Mojo vs usual chips. Very visual and self understanding. I like it.

 

[x RELIC x]

I had big plans when I got the idsd.  it was gonna be my desktop on portable, but after lugging the thing around a couple of times in my pocket.  I decided the it wasn't gonna work out.

Was gonna replace the idsd with the mojo but after some more reading and watching reviews.  I found out that mojo cant have multiple sources connected to it.  It won't differentiate which source to play or take priority. The idsd, I have both my comp and xbox one connected to it right now.  If i feel like watching some youtube videos while im on the xbox, i will just play the video and the idsd will automatically switch to comp and switch back to xbox when i'm done watching the video.

Don't know what you watched or read but you can have multiple sources connected and the Mojo does have a priority on its inputs. USB > coaxial > optical.

 

[Mython]

An old favourite has genuinely stunned me. Ocean Colour Scene-Marchin Already just sounds so different. I saw them live many times as they are great musicians and are fantastic live.
This album through Mojo has never sounded so good.I know recently a couple of posters mentioned 3d imaging and width was less than good. Listen to this if you want to hear what Mojo can do.
The album is so much more fun. Energy just oozes. It reminds me of them in concert. I wish I'd played it when I bought Mojo 3 months ago.
I'm off to play it again

 
There are a couple of nicely-recorded Ocean Colour Scene tracks on their old album B-Sides, Seasides, & Freerides
 
https://www.youtube.com/watch?v=0NBTnGBkeIM
 
The CD is well worth getting, and would sound superb through Mojo.

 

[headmanPL]

Thanks for the tip. I don't have that one (yet)

 

[wym2]

Got my Mojo. But why i dont feel "wow"? Somebody explain?

 
While I can’t explain why you don’t feel a “wow” experience, I wonder if you can tell us how you have set up your system and how you are using the Mojo in it.
 
 
 
MBP → SDragon → Mojo → AQ Sky → LC

 

[twiceboss]

While I can’t explain why you don’t feel a “wow” experience, I wonder if you can tell us how you have set up your system and how you are using the Mojo in it.



MBP → SDragon → Mojo → AQ Sky → LC

Yes, that's the thing i wanna know. For now, i just directly connect usb with my computer. Still a so so performance. I need what kind of connection should i do to make it sound good!

 

[warrior1975]

That graph is just the visualization of the smooth and liquid sound of Mojo vs usual chips. Very visual and self understanding. I like it.

I don't that graph was meant for the MOJO. Maybe Joe Bloggs can clarify. I think that's the curve of a dac using up sampling. I don't know, I'd have to read what Joe posted a dozen times to even begin to understand what he was saying.

 

[RedJohn456]

Yes, that's the thing i wanna know. For now, i just directly connect usb with my computer. Still a so so performance. I need what kind of connection should i do to make it sound good!

to be honest, using a better connection will yield a cleaner signal, but will not change a sound night and day. You have 60 days to try it out. The best thing I can say is that use the Mojo and mojo only as your main dac and let your senses adjust it. If after a few days or a week you don't feel any improvements in your enjoyment I would say perhaps it will not fit your sonic preferences.
 
What are you using as your music source btw? Like 320 kbps mp3? Flac? Might be an issue there who knows

 

[twiceboss]

 
to be honest, using a better connection will yield a cleaner signal, but will not change a sound night and day. You have 60 days to try it out. The best thing I can say is that use the Mojo and mojo only as your main dac and let your senses adjust it. If after a few days or a week you don't feel any improvements in your enjoyment I would say perhaps it will not fit your sonic preferences.
 
What are you using as your music source btw? Like 320 kbps mp3? Flac? Might be an issue there who knows

320 and above. I have few flac files. Many 320 and also 320 from Spotify.
 
Yes, i will use Mojo for my main dac. Let see how it goes

Just change the Kernel Streaming though

 

[RedJohn456]

  320 and above. I have few flac files. Many 320 and also 320 from Spotify.
 
Yes, i will use Mojo for my main dac. Let see how it goes

Just change the Kernel Streaming though

Spotty is my main music source as well, do u have ur streaming quality set to extreme? 

 

[twiceboss]

 
Spotty is my main music source as well, do u have ur streaming quality set to extreme? 

Yes, but desktop is only High Quality. Do we manage to get Extreme Quality in desktop?

 

[RedJohn456]

  Yes, but desktop is only High Quality. Do we manage to get Extreme Quality in desktop?

my mistake, you're right

 

[echoz]

My desktop mojo setup:-
 
Imac-ipurifier2-ifi usb power-gemini cable-mojo-heaphone/amplfier to speakers.