6DJ8 vs. 6922?

My favorite is the Valvo CCa and second is Amperex PQ 6922 used in my Pathos Classic MKIII.

The Suitability Of The 6DJ8 For Audio

I just switched a 2c51 tube in my MHDT DAC with a 6922 with adapter better bass and bigger soundstage

Every piece of gear that I have owned that uses 6DJ8 tubes, I have had great success with 6922 & 7308 tubes.  All are interchangeable.

In addition, my absolute favorite is the PCC88 (7DJ8).  I have NEVER had a problem using these in ANY unit that uses the 6DJ8 family of tubes.

The National's are my favorite, (thanks Kevin!).

are 6DJ8 and 6922 tubes inter-changeable

yes in all cases

the question of preferences is very long to answer, and highly dependent on what gear the tube(s) are being used in and what sonic profile is sought - different circuits and applications have very different sensitivities to the specific make/type of 6dj8 used

in general, excellent 6dj8 variants are old stock usa or european made ones from rca/amperex/philips/mullard, though very good quiet ones, especially matched sets, are getting expensive

more cost effective options are old stocks from japan and eastern europe (hungarian tungsrams , yugo made ei's, czech made teslas)