Warm sounding 6922 Type Tubes

@ronrags 

I think it’s going to be hard to find a tube warmer than the Mullards. Mullard has always had the reputation of being THE warm tube.

There maybe tubes that do sound warmer in your system but it would be a case of that particular synergy with your equipment. For example, the Amperexes mentioned above are not known as a warm tube and from my experience with them I wouldn’t call them warm, but they could, by chance, give you the sound you want.

I suggest you call Brent Jessee, Andy Bouwman (Vintage Tube Services) or Upscale Audio to see if they can recommend something for you. These guys are all very knowledgeable about tubes and will talk to you about tubes that may be what you’re looking for. Good Luck!

P.S. RCA Blackplates also have a reputation for being a warmer or smoother tube.

@gregdude has an idea. There is a tube seller named Tubemonger. They sell socket savers and adapters. One of the adapters allows you to plug a 12XX7 tube into a 6922 socket. Here’s the link:

Tubemonger tube adapter

Before you try a tube adapter, I’d talk to someone knowledgeable about your DAC and Brent Jessee as well as the people at Tubemonger to make sure it’s a good idea for your DAC.

The link says it adapts to an ECC88, which is what the Europeans call a 6DJ8.

Yes @bdp24 -  Siemens and Telefunken made them for the German communications industry. 

CCa tubes are not a sure thing though.  Later vintage Siemens are known to be bright sounding and I don't think the Telefunkens are as highly regarded as the Siemens.  So as with all things tube related, do your homework.