This is just IMHO but after updating my DAC 2X to the new version 2 I feel it is a significant upgrade although expensive. My observations are better vocals both male and female. There also seems to be
be more weight to the music and improved but subtle detail. I posted this as an insight for other DAC 2x
owners who maybe considering this upgrade.

@tomr1 Are you using the USB input? If so, its supposed to be much improved on this new version.  I'm considering a used DAC 2X and would eventually upgrade to the V2 if I decide to go this route.  
Yes I am using the USB input with an Audience AU 24 SE dual lead
If you decide to buy a used DAC 2X make sure it was manufactured
in 2016 or later as their were improvements made that you will need in order to do the Version 2 upgrade.
I have a 2012 DAC2X which was just updated to V.2 (DAC2X V2) at the company without any problems or special charge because of its age. The upgrade is well worth it. It took an excellent DAC and made it significantly better.
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I am the guy who started this discussion and my response to glory
is I have tried several other high end DACS including the Bricasti SE,
the Berkeley Audio Reference MK1 the MSB Analog and the Linn
Klimax and IMHO it is the best of them more musical.
I have dac2x and am considering to upgrade to v2.
tomr1, what source you are using with dac2x? computer or network stream server?
I use aurender N100 with dac2x and wonder how much difference the v2 usb galvanic isolation  will add? 

Does adding a Uptone ISO usb also improve sound ?
I own 2 CD transports and thousands of CDs so always interested in redbook sound quality from any DAC.
I really wish I could give you an opinion on your questions. But I
have no experience with Uptone audio. I also don't know if the EMM
labs  new galvanic isolation is the reason for the improved sound,all
I know is the upgrade has made a substantial improvement in sound