I know that old stock 6AS7Gs dont typically work as well in place of the newer types that Ralph sells. The same may be true of 6080s.
My advice would be to concentrate on the 6SN7s and to leave the power tubes alone at least for now. Not all sections are equal in terms of sonic impact and it may be that you need a pair of GTA or GTB in one section with GTs/5692s being acceptable elsewhere. Call Ralph and he will clear this up.
I have retubed Atma-spheres before and my clients have reported positive results using old stock 6SN7s. I have never replaced any power tubes. Mixing 6SN7 pairs with different strengths seems to yield positive results.
My advice would be to concentrate on the 6SN7s and to leave the power tubes alone at least for now. Not all sections are equal in terms of sonic impact and it may be that you need a pair of GTA or GTB in one section with GTs/5692s being acceptable elsewhere. Call Ralph and he will clear this up.
I have retubed Atma-spheres before and my clients have reported positive results using old stock 6SN7s. I have never replaced any power tubes. Mixing 6SN7 pairs with different strengths seems to yield positive results.