Best 6922 tubes for DAC


I am thinking about replacing the stock Sovtek 6922 in my Audio Logic 24 MXL dac. Can anyone recommend NOS that would work well in this dac? Please try to describe sonic characteristic of the tubes you are recommending.

Rest of the system:

Joule Electra LA 100 preamp and Stargate amps, Merlin VSM speakers, Sony X707ES modified transport, Cardas and Stealth cables.

Many thanks!!
drv
I have tried several in my MXL. The ones that are most pleasing to me are Siemens CCa.
If you do a search in the forums for "Audio Logic", there are a few threads about this topic. If I remember correctly, several people preferred Mullard and Tungsram.
Anything by Phillips (e.g. Amperex, Mulllard) will be a huge improvement over Sovtek. I'd recommend Amperex Bugle Boys or maybe 7308s for the ultimate upgrade.

-Ed
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I am using Philips Miniwatt 'SQ' in my 24MXL- very full-bodied across the spectrum, perhaps ever so slightly less detailed than the Siemens, but more full-bodied bass IMO, and a wonderful midrange...