I'm not a Spatial owner, but would love to check out the X-series one day. I am using Cube Nenuphar Mini's, which are great but not flawless. Anyway, I was reading this thread because I just spent 3 months using the LSA Voyager 350 ganfet amp. I usually run tubes, but during the summer they get too hot so I use something else. Since my speakers like amps with little or no negative feedback and I wanted something that ran cool I decided to try the LSA. I've tried Class D before and never loved it. Sounded ok and all the detail was there but just never felt engaged into the music. The LSA was the first class D I could live with and really enjoyed. I originally planned to sell the LSA after summer but I enjoyed it so much I'm thinking I might keep it for next summer. I just hooked my 845 tube amp back up and actually miss some of what the LSA brought. My system is Auralic G1 --> Holo Audio May KTE --> Holo Audio Serene KTE --> LSA or tube amp --> Cube Nenuphar Mini's + 2 Rel S/510s, all plugged into a PS Audio P12 regenerator. With the LSA there was amazing detail but also a crystal clear transparency. String plucks sounded like you were listening with a stethoscope and could hear every micro detail. Voices captured every nuance and inflection. It was almost hyper-detailed, but never harsh, dry or etched. When I plugged my LM518 845 amp back in yesterday I did lose some of that extra detail. With the LSA, piano sounded like you were in the piano. With the tube amp, you're at a concert in row 10. I do like the tubes however for the more liquid mid-range. There's an organic sound with tubes that just sounds right to me, but I love having this ganfet amp around in case I want to change the flavor or play with other speakers (I did use it for a month with some Usher BE718's and it sounded fantastic too). While the Nenuphar Mini's are not Sapphires, both are relatively efficient and I would highly recommend checking this amp out if you're looking for class D.