1. This site uses cookies to help personalise content, tailor your experience and to keep you logged in if you register.
    By continuing to use this site, you are consenting to our use of cookies.

    Dismiss Notice

Chord Mojo DAC-amp ☆★►FAQ in 3rd post!◄★☆

Discussion in 'Portable Source Gear' started by Mython, Oct 14, 2015.
First
 
Back
938 939 940 941 942 943 944 945 946 947
949 950 951 952 953 954 955 956 957 958
Next
 
Last
  1. betula

    I have an impression reading your posts in different threads, that you tend to judge equipment superficially and too quickly. Also changing your interest and purchases too quickly.
    I'd suggest you to spend a few days with Mojo, discovering the sound it produces. If you don't start to like it in a couple of days, then just sell it, as it is just not for you.
    But if that will be the case in a few days, you should really stop for a moment, and find out what exactly you are looking for in audio world.
     
    Peter Hyatt likes this.
  2. twiceboss
    I just throw my opinion for the first impression. But meh, i dont need to sell it since Sonicelectronix gives the customer 60 days a full refund guaranteed. Much time to audition it. No worries!!! :wink:
     
  3. warrior1975
    Ok, I did it. Mojo will be here on Friday!! Hope I like it. I have a good week to use it before my girl gets back. Should be plenty of time to determine if I like it or love it.
     
    spook76 and Peter Hyatt like this.
  4. bavinck

    See now, in general use I am more convinced of brain burn than equipment burn. However, each must decide on their own.

    My point about the Mojo is, it is math that makes the Mojo so great (Rob's algorithm that is doing the waveform conversion) . That will be occurring from the first second the Mojo is turned on, so equipment (possible?) burn in is not even a part if that equation. However, as Rob has said several times (and others have noted as well) it does take some time for us to become adjusted to the better waveform generation (brain burn in) .
     
  5. bavinck

    I think you will like it, congrats! What iems you using?
     
  6. warrior1975
    I ordered tralucent-audio-ref 1 too, should have by end of the month. My current collection is rha T10, Sony Xb90ex, and Heir Audio 8.a. Fostex Th900 headphones too. My goto IEMS until the Ref 1 Too arrives are the Sony Xb90ex. I've recently sold most of my IEMS, so time to add new toys.

    Forgot about my asg g2.
     
  7. bavinck
    Mojo rocks:
    20160323_142248.jpg
     
    opienor likes this.
  8. psikey

    Switch to Tidal streaming in UAPP then.

    Sent from my SM-G935F using Tapatalk
     
  9. jincuteguy
    Where did you order the Tralucent Audio Ref 1 ?
     
  10. warrior1975
    From Gavin, spkrs01. PM is best.
     
    Mython likes this.
  11. Joe Bloggs Contributor
    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:

    comparison.png
    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.

    This analog filtering would occur the same way, regardless of how high the sample rate of the upsampled sample stream. As mentioned at the start, a really low upsampling factor (like 2x) would require the use of a steep analog filter, which in turn may lead to small amounts of phase shift at high audible frequencies, but this isn't an issue at all at 16x.

    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
     
  12. Peter Hyatt

    How much time have you invested?
     
    Also, go to something you are very familiar with and listen for detail.  
    Go back to the same song, sans Mojo, listening for the same detail.  
     
    With the massive amount of data being interpreted by the brain, it is going to take time.  I am enjoying keeping track of songs, specific parts, and the instruments and clarity that is impressing me.  As the days go by, it continues to amaze me.  
     
  13. bavinck
    Oh man, this is getting good. Rob, can't wait to read your response!
     
  14. bavinck
    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?
     
  15. headmanPL
    So having been on the road with Mojo this week, I have listened to a varied range of music. At times it's amazed me. Many classical music pieces have left me open mouthed at how different (good) it can sound.
    Beatles tracks have been great fun.

    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 :grinning:
     
    SteveOliver likes this.
First
 
Back
938 939 940 941 942 943 944 945 946 947
949 950 951 952 953 954 955 956 957 958
Next
 
Last

Share This Page