Tube Rolling a Rogue Cronus Titan integrated amp


Hi this is my first post so please forgive any mistakes made thanks in advance.
I own a Cronus Titan integrated (Non Magnum version). I purchased this off E bay in the UK  where I live and to be honest it was a nightmare needless to say I had the Amp repaired by an extremely good Electronics engineer so didn't lose out too much financially.
The Amp was finally as it should have been :-)  and I have lived happily with it for the past 2 years, however( as always) the need to tinker has bitten me again so having read a few posts regarding said amp I have ordered a Matched Quad set of Gold Lion KT66's 

Now for the important bit 
I'm not technically minded especially with electrics what if any thing would I need to change on the amp to accommodate the valves as in biasing is usually set @ 35 on the meter( if that makes sense)

Sorry for the long-winded post and thanks for having me 
johnnylambo
Received wisdom is that the preamp tube, the single one at the front (shared by both channels) makes the biggest difference.  Depending on what direction you want to go in, any of the usual suspects would be worthwhile: Mullard, Amperex, Brimar, Telefunken, etc.
  Talk with Rogue
they have fantastic customer support
the front end tube will make the most difference as @twoleftears. Has aptly pointed out 

also try listening to different output taps, that can make a dramatic difference and is free!!!
Hi all, 
E-mailed Mark @ Rogue and he's categorically stated that KT66's shouldn't be used

"  I would definitely not use the KT66 as the plate voltage is too high for that tube."

Which is a bummer saying as I had already ordered them so have to try and exchange them for Gold Lion KT77's and a Telefunken pre amp tube on his recommendation.

And yes  they are second to none in the customer support role as well as their products.
Have fun everyone :-)
If you want warmer, a little more "tubey" sound (the Rogue standard isn't very much) try a Mullard NOS in the preamp socket.