Surface Thunderbolt 4 Dock

[Deleted member 68540]

Both the Microsoft Surface Thunderbolt 4 Dock and the Lenovo Thunderbolt 4 Dock sport a Conexant CX21985-10Z DAC chip. I'm using the MS one (teardown here: https://dancharblog.wordpress.com/2023/04/07/surface-tb4-dock-teardown-and-review/) and Roon says it is able to put it to decode and render MQA files and play them in lossless mode (up to 352kHz in my test).

I'd be guessing it's Roon itself doing all that (rather than the chip), but the dock sounds pretty OK to me + I have been able to play an MQA-encoded FLAC file in it with Foobar2000 as well.

Has anyone tested these things -- i.e. docks like these and their sound? Are the Conexant chips just like Realtek chips one usually finds in PCs and that's it, or is there something else going on?

 

[voodooless]

It seems to be a USB-C audio codec with headphone amp. It supports UAC2 up to 24 bit/96 kHz, 87 SINAD, and probably can’t drive headphones very well. So nothing special at all.

It’s really hard to find any info though, so may not be 100% accurate. The only thing I found is here.

 

[Deleted member 68540]

Thank you so much for unearthing that. Agree that it does not sound very promising -- not even as good as the Realtek, in fact!

How would you explain the Roon info? (playing via WASAPI Exclusive with Roon MQA core decoder disabled).