The ones I had with my F7 were the Manley Shrimp (tube pre with low output impedance), Wyred4Sound STP-SE stage 2 (mostly no gain), and DIY Pass B1 (no gain). I wish I’d had the eastern electric minimax or LTA MZ2 I have now, I think those would have been my favorites, with the wyred and shrimp coming next (but it’s all system-dependent! I have Devore Nines speakers, at 91db FYI).
