"Gaia superior to Singxer in usb isolation on input and implementation of OXCO clock on I2S. Singxer SU6 as good as it is, simply doesn't play in same universe, build quality, design, parts quality in Gaia all far superior. Meaningful improvement in sound quality reflects this superiority,"
I never owned the Gaia, but I did own the Hermes and had problems with it requiring me to send it back to Denafrips, although that may have been a fluke. I do see the potential advantage of the Gaia DDC when using Denafrips' Terminator DAC since it offers the ability for clock syncing.
I am not here to argue about sound quality between DDCs, and I am not promoting the Singxer SU-6 so I don't really have a dog in the fight, but I can say that inserting the Singxer did nothing to degrade the sound of my system and that it has worked reliably the entire time I have used it. Here are links to review measurements of both the Singxer SU-6 and the Denafrips Gaia by the same reviewer. The SU-6 was reviewed a couple of months prior to the Gaia and below are some conclusions by the reviewer,
"Overall, the Gaia is an excellently performing DDC.
It falls ever so slightly behind some other choices like the DI20HE and SU6 in performance, but the added features, and matching aesthetics with Denafrips dacs may be more important to many."
and,
"Those wanting the absolute best performance should still look to the Singxer SU6, but for the added flexibility of non-USB inputs, 768khz support, dual AES output, and a matching aesthetic for Denafrips DACs, the Gaia is a great choice."