Replacing 12AU7 tubes in a Prima Luna Dialogue integrated amp

Don't swap the same or stock tubes from socket to socket as it will not make any difference. Of course I doubt this is what you meant lol?  If you like the stock power tubes or the tone the EL34 present then you might want to roll in some driver tubes for example like some Cifte 12AU7 in the front 2 slots. These make the MOST difference and Kevin Deal will tell you the same thing. If you want a little more pop or dynamics to the sound then try a power  tube in the KT family such as a KT88/150.  Or even a Gold Lion KT77 which is closer to a EL34 but with more extension and drive. Its kind of like a hybrid tube.  However, enjoy the amp as it is and make sure it is broken in well and your ears to the stock sound and then make an evaluation. One step at a time trust me :)

Have KT88's in the amp.  Looking into the TungSol KT120's.

Will look into the Cifte's.  All this is new and I get the fact different tubes have different tonal/power quantities, but I'm not a "tweaker" who really wants to get into buying boxes of different tubes and spending days plugging them in and out and looking for somewhat subjective improvements.   I'll make a few minor adjustments but for the most part am happy with the way it sounded the past two years with the Prima Luna Silver AU's and stock KT's.  Replacing with the PL Gold. Maybe the 2 Clifte you note.

But as one's gone and time to replaced figured a bit of minor research for a simple upgrade was worth looking into.

Thanks very much for the info.

Yes research is good but only you know what your ears like. I didn't care for the KT120's at all.  The 120's had too much glare or upper midrange energy for my tastes. Maybe not your tastes however.  I had no idea you already had KT88's in the amp as it usually comes stock with EL34.  Oh wait I just noticed you have the Dialogue and not the Dialogue Premium so that explains it.  So if you like the KT88 sound then what are you hoping to achieve or want to achieve? Would you like more warmth or maybe more detail?  Mullards will give you warmth and Cifte some detail and openness without any harshness. 

Before making any decisions I would call Upscale Audio and speak with Kevin or Jarod. Trust me he knows better than anyone PrimaLuna and tubes. Also look at the reviews on his website and that will also help and give you some insight. 

Was thinking they may bring a bit more depth to the mix, maybe a minor enhancement/separation to the midrange.  Not that the KT88's sound "bad", Just figure after 2 years maybe try something new.