So when I started this thread I was having some issues with the soundstage width and depth of my M3’s. I knew that it wasn’t Claytons speakers. I had done some major acoustic treatments diffusion and absorption which seemed to help but still there was something missing. I have always owned Solid State gear and it was all good. I have been toying with possible tube amps, tube preamp/SS Amp combos, Hybrids etc. It wasn’t until I demoed my first tube amp in 50+ years of listening that I really am beginning to hear the magic. I happened across a great dealer who let me take home an Octave V40se and WOW, I’m a believer! So now I have a V70 Class A on order and I am convinced that tube amps and tubes in particular are so very critical to increasing and defining your soundstage. And yes I will experiment with the power and driver tubes as that will indeed make a significant difference as well. The Octave and the Spatials are very special Still learning stuff at 60 years old and that makes me feel like a kid again! So the Octave can use a variety of power tubes KT120, KT150, etc and driver tubes ECC81 and ECC83’s. Any specific ones new or NOS I should seek out?