Where to insert tubes while running a Luxman SS integrated

I don’t subscribe to the notion that you can sprinkle in some tube flavoring and get a substantial improvement in sound.  The fundamental electrical component that matters most, and will determine the basic kind of sound one will have is the power amplifier.  Given the wide difference in the sound of different tube amplifiers, and given that compatibility of tube amps with particular speakers is critical, it is imperative that someone investigating tube gear experience different amp/speaker combinations.  

OP, if you are poised to purchase Tannoy’s in near future, I would not spend a dime on any other component now. It’s important to get the synergy right between your Integrated and Speakers. Adding a DAC or phono is not going to mask the issues between Luxman and R3S. I have been down this road where I kept on upgrading upstream components instead of addressing the real problem. Having heard Luxman Integrated, I do not believe Luxman is a right match for your R3S or Tannoy’s. 

If you still feel the need to insert tubes the Luxman integrated is probably not the one for you. 

@lalitk sounds like words of wisdom.  Do you have any speaker recommendations in the 4-6k range to run with the Luxman?

@mapman perhaps not, but I’m very satisfied with the combo when I play my good vinyl pressings and even some well-recorded digital.  It’s really bad pressings and some digital that become too harsh (which the R3s do not mask at all—I had the same issue, perhaps slightly worse, when I was running them with the Cambridge). The dilemma is if those particular recordings/pressings can be masked/improved by adding something else to chain.  Or maybe I just need to move to warmer speakers.