I got an SR Purple to complement the Master Fuse in my two fuse HM1 amp, and I was really surprised with the result. I had been using two M1s, then Master Fuse+M1, and now Master Fuse+Purple. Let me say, these two go together like peanut butter and chocolate and I am hearing things I’ve never heard before. Incredible synergy.
With just the Master Fuse I was getting this big soundstage, diffuse, U shaped FR, and treble-leaning sound. Now, the images are so distinct and dense it’s crazy, and they have a tube-like glow. Just a little bit of the Purple mid-bass bloat, and a little bit of dynamics lost, but so much more dense and tactile than the Master Fuse alone.
At this point I think it’s fair to say you need both to get the full effect. Much bigger effect than I expected adding the Purple. Considering the M1 is excellent in its own right, and perhaps better than the Purple in many ways, but the combination with Purple and the Master Fuse is so much better. So vibrant and dense.