I auditioned an Audiopax preamp - think it was a model 5. I could have lived with it quite easily, it was the most valve sounding non-valve preamp I've heard. What prevented me pulling the trigger was that I already had a Herron VT2 and the Audiopax, although more versatile was not ultimately better sounding than the Herron. I would have been hard pushed to tell them apart if I was blindfolded.
PS Audio Directstream DAC, modified Dennon DVD player, SP10, Trans Fi linear tracker, Stack audio streamer
1980's Aloia 6L6 prototype, Cat's Whiskers Autum Leaves 300 B mono blocks, Definative Audio modded Rogue 88 Magmum 6550. Firebottle LDR battery pre. Classe 103, Herron VT2
RFC Tannoy Cheviot's,Wilmslow Audio modified Chario Academy Millenium II's,Frankenstein DIY's, Oris Onken horns, Fostek full range drivers
Ripnas etc