I have been seduced back to valves and recently went on a mission to find a new power amp to drive the AG's. I heard some lovely kit, including Kondo and some unobatnium DIY stuff, but finally settled on Living Voice's reworking of the Argento. This unit has some of Kevin's finest handiwork and components inside and is intended to appeal to the buyer that doesn't have the £50k+ budget needed to get into Gaku-on/Gaku-oh territory.
The most obvious addition is a separate external filament heater power supply connected by an umbilical to the main unit. Art Audio supply the Argento to LV 70% built and Kevin does the rest. Inside is the full complement of foo and faerie magic.
The amp was primarily designed with OBX-RW speakers in mind, so the specs naturally favour that speaker - PSE 300b kicking out 20W. On paper this shouldn't really work with the Nano's having too high an input sensitivity, too much gain and too much power. But despite everything, it does!
I often felt a vague sense of confusion and disappointment on leaving Definitive's wonderful listening rooms, that room differences aside, I could never really get close to the musical presentation they achieve there. However with the M7/Argento combination I feel I have made huge strides towards it. The sound carries the wonderful SET characteristics of beautiful tone, ease and naturalness. Crucially though, the Argento has a massive room-filling quality to the presentation, and it has the balls needed to really rock out when needed. Until the next forum fad appears, this one has certainly cured the box swappingitis.
Thanks to coco-san, I have some great pics from a listening session we had on Friday night. Cheers matey