DK Design VS- Reference vs Signature

Larry, I am about to start rolling the tubes on the mk2. What tube would you recommended with the DK mk2 that will better enhance its overall experience? More detail, articulation, mid range, purity, air, bass,and etc.

Thanks... Do they sound better than the Seimens cc88/2262. I have read plenty reviews on these. Are the amperex and mullard better than the seimens?

Larry, thanks you very much....You have a lovely product and I am one satisfied customer. I really love the way this amp sound. Another question, Can you please give me instruction on how to install it. One thing I know for sure is I will have it unplug when I install it. I am assuming the only thing I have to do is disconnect the top of the amp with an alley wrench. Once disconnected the amp, remove the tube then put the other in the same way I took the other out, right? Is there anything elso I am missing.

LARRY YOU ARE THE MAN!!! This is excellent service for an excellent product.

Thanks

Larry,
When I took the older pair out and replace it with the new pair. Every thing was fine. But when I put the older pair back in, the right channel tube lost its vacuum. It stop lighting up. I really don't understand how this could have happened. Can you explain to me what happen and How can I prevent this from happening?
Ron