Six DAC Comparison

I find it extremely curious Mojo doesn't provide I2S input. On one hand I understand optimizing usb inputs as seems to be de facto output on most streamers. On the other, why do the extra conversion vs. native I2S path in dacs?

Recently I purchased Denafrips Gaia in order to compare I2S vs usb in various dacs. With my Laiv Harmony I2S via Gaia was far superior to usb. Now its fair to say, based on descriptors, usb implementation in Mystique superior to Harmony, so difficult to extrapolate here.

A fairer comparison of I2S vs usb will be with Musetec 006 which has more greatly optimized usb vs the Harmony, something along lines of Mojo. While I understand this is only a single aspect of usb implementation, both Harmony and Mojo use femto clock, Gaia has superior OXCO clock, I believe large part of improved sound quality I"m getting with Harmony slaved to Gaia clock is due to the improved clocking. Seems to me Mojo should at least offer I2S, easy to implement as its native path, doesn't need all the usb complexity. In any case, I'll be comparing better usb in Musetec vs I2S in coming weeks.

Keep in mind I have very similar usb implementation as @mitch2 as I also use full Sonore optical conversion, in other words OpticalRendu is the streamer with usb out, usb optimized in both our setups.

Benjamin's take on clocking can be found in here - scroll down to Myth #1-Clocking.

Regarding I2S, it was primarily designed for internal use - short runs inside of equipment, which may be a reason there is still no universal standard.  When I owned Metrum equipment, I heard no improvement when using the I2S input to my Pavane or Adagio DACs.  In fact, with my system at the time, I liked the sound of the USB input a little better, but that required taking the Ambre streamer out of the mix so maybe it was apples and oranges.  With the Singxer SU-6 DDC, I do have the option of using I2S and adjusting as needed to match specific manufacturer's versions of I2S.  Unfortunately, I have not had an I2S capable DAC here since I acquired the Singxer.  I wish I had it at the same time I had the Tambaqui here because I heard from a dealer that the Tambaqui sounds best through the I2S input, at least in that dealer's opinion.

I2S or 110 ohm  they both are top for connection.

they are not a myth, if that were true then why do Top companies use them ?

it comes down to how comprehensive they are implementing the connection

plain and simple . For example if you use a xlr  that does not mean the circuit is true balanced input to output . That’s my only point , Esoteric for just 1 example makes very $$ expensive and comprehensive dacs ,transports with I2S as their top sounding input , 110 ohm xlr can be excellent also .for a truly Great I2S cable you don’t want a generic cable with video more issues.  Tubulus Dedicated just for Audio IMO makes the best per $$ in quality ,value cables .this I2S cable will compete with cables 3-4xthe cost ,this too applies to their USB which I have and next year a statement usb cable too will be coming out. read their formula, they give you the basics about their design ,very sound and make a lot of common sense but very labor intensive.,their  top Ximius -I2S  is Great I  just ordered one as well as their top Ethernet cables ,,they will totally change your opinion of what digital can sound like I highly recommend their top 2 cables ,which have much more in depth shielding and other methods. Unless you own them you  have no valid opinion.!!

I agree 100% with Benjamin on the clocking part. The real myth is accuracy of the clock makes it sounds better not that an ocxo will sound better. Ted Smith of PS Audio has given similar explanation for audio, in the time domain small quanta accuracy is all that is needed rather than long term stability and yet we see OCXO clocks, which has the best long term stability, almost sounds better than a regular Femto/TCXO.

Moreover, it’s a given fact, and somewhat similar to I2S, that the proximity of the clock is important since it can significantly reduce emi and yet we see external master clock with 1M clock cable sounds better.

I have seen in some implementation with external master clock, a modestly priced 10Mhz OCXO did not improve the performance of the DAC until a very expensive one were used. This is very inline with what was described in the Mojo article regarding lower hash noise - the modestly price ocxo did not have a better hash noise than the internal clock itself and only when the expensive one was introduced did it improve the performance. I bet if we measured both these external clock in terms of accuracy in the time domain, we would be hard pressed to find any differences.

But having said all these, I am surprised that Mojo doesn’t employ an ocxo in their higher end dacs even when they believe it can improve the performance or maybe they did experiment and found no appreciable difference in how it sounds. Curious.

I'm using the most current USB driver.  For Windows it doesn't show up as Mystique but works just fine.  I've also tried an older driver which sounded the same so I reverted back figuring they must have a newer version for a reason.

@danager thanks for the info. Are you using the Thesycon or the Xmos driver from the JL Sounds download link ? Do you remember ?