Hi there!
I am a former owner of a DK MKII and I bought a fair number of tubes to try in the unit(around 10 pairs). My favourites were some Rayethon branded Siemens & Halske 6DJ8 from the 60's. I also enjoyed the Telefunken E88CC and Mullard E88CC's that I tried. The biggest problem that I had when tube rolling was that the majority of the tubes that I tried were noisy. You get a feel for the signature of sound that each brand gives but noisy tubes became a nuisance to me and I ended up learning the hard way that someone like Andy at Vintage Tube Services is the only way to go if you need quiet, properly matched tubes. Here is a list of everything that I tried, best to worst:
Siemens & Halske(Rayethon Branded)NOS-6DJ8
Telefunken E88CC
Mullard E88CC
RCA branded Siemens&Halske 6DJ8(great sound but noisy)
Amprex USA 7308
Phillips ECG 6DJ8
Amprex Holland 6DJ8
Fivre 6DJ8
Tungsram E88CC
Westinghouse w/Germany 6922(newer stock I think)
Counterpoint branded 6DJ8
All that being said, you will likely find that most people prefer the grey plate NOS Siemens & Halske in the DK which I would definitely agree with. The CCA's are supposed to be the best but finding a quiet, non-microphonic pair might be tough. Best of luck...
I am a former owner of a DK MKII and I bought a fair number of tubes to try in the unit(around 10 pairs). My favourites were some Rayethon branded Siemens & Halske 6DJ8 from the 60's. I also enjoyed the Telefunken E88CC and Mullard E88CC's that I tried. The biggest problem that I had when tube rolling was that the majority of the tubes that I tried were noisy. You get a feel for the signature of sound that each brand gives but noisy tubes became a nuisance to me and I ended up learning the hard way that someone like Andy at Vintage Tube Services is the only way to go if you need quiet, properly matched tubes. Here is a list of everything that I tried, best to worst:
Siemens & Halske(Rayethon Branded)NOS-6DJ8
Telefunken E88CC
Mullard E88CC
RCA branded Siemens&Halske 6DJ8(great sound but noisy)
Amprex USA 7308
Phillips ECG 6DJ8
Amprex Holland 6DJ8
Fivre 6DJ8
Tungsram E88CC
Westinghouse w/Germany 6922(newer stock I think)
Counterpoint branded 6DJ8
All that being said, you will likely find that most people prefer the grey plate NOS Siemens & Halske in the DK which I would definitely agree with. The CCA's are supposed to be the best but finding a quiet, non-microphonic pair might be tough. Best of luck...