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
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...
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I recently upgraded my amplifier's input tubes from Sovtek 6922's to EH 6922's. They are very similar, with better bass response coming from the EH tubes. You might give these some consideration, at $20 each new with gold pins. Don't go down the NOS road unless you've got so much money that you've forgotten what One's and Five's look like, and you'd better have reliable sources, because (IMHO) many of the NOS tubes circulating through cyberspace right now are actually OOS tubes (Old Old Stock) or just plain OJ (Old Junk).

Cheers and Good Luck