I bought AudioBear's combination used from here this March (reluctant sale -now I know why- but was in a second system). I've a Gryphon TABU Century (with PS1 phono), purchased for the phono (nice amp thrown into the deal to boot!) a decade ago. I tried RWA's Sig30 with RC for a second system but no question, my Gryphon is and was my reference (have a MWI 9100ES CDP too, audiomeca Romance ZuDL103R TT).
I played a bit with the Promitheus' both single-ended and balanced into my Gryphon to hear if it was worth the effort and it wasn't. I went into my RWA but my 'Ref' reigned. I went to sell my RWA and the DACT had shorted (?) died so Vinnie (RWA) kindly told me where to cut the wires and now I had a simple power amp. So meanwhile I was 3rd generation Zu Audio speaker fan with the Druid MkIV, then Credenza & MiniMethod and finally the Essence.
I tried the Promitheus' with the power RWA and the Credenza and 'think' I heard a marked improvement without the DACT (stepped volume attenuator) in the signal path. A lot more 'air'. BTW, meanwhile I was getting pretty good at resonance-isolation and the Promitheus' (Russ Andrews' oak feet, cork pads here and there...). Still packed my 'amps' up after audition and off to the cellar they went. BTW, RWA & Promitheus were offered for sale but nobody serious (so many nerds out there!). Meanwhile I've my Zu Essence and after experimentation, there still sits my Gryphon...
Over at Lenco Heaven I asked about an OTL design (Futterman) and Scott pointed me towards Atma-Sphere. For those in the know (I wasn't till recently) the nominal 12 Ohm Zu's and OTLs are 'perfect' for each other. The Atma-Sphere importer (Germany) said he'd be pleased to give me a home demonstration and that was five days ago.
Atma-Sphere have single-ended inputs but shine with their balanced. I read this and got out my Promiteus' and let them warm up all day for the audition. I guess this is anti-climatic: Using Gryphon Guideline II between the Promitheus' and German HighEnd (engineered, pure silver) for balanced as ICs, Zu Libtec speaker wires into Essence, after thirty minutes a transformation took place that still has me "gasping for air," in that I mean 'we' were blown over - amazed, dumbfounded at how good the sound was. My Promitheus' are no longer for sale and I'm deep in negotiations for an Amta-Sphere amp (either S-30 or M-60).
The rep had his wife along. She's cool, knows her way around hi-fi and is quite 'good' at hearing (that the rep knows, is clear right?). The rep was so impressed that he's now most unsure about an investment in new speakers, whether he still wants to invest over $13k (industry complimentary price ~ 20k EURO reg. sales price here...) he's aimed for, or to go with the Essence.
My Gryphon may have a '9.7' in deep bass etched inner-detail but the Atma-Sphere hangs close with 9.5 (transition to not notice or care took me much less than a minute)... I have heard so much good stereo kit over the decades, but nothing (even Pass with Avantagarde Trios), that got me anywhere near as involved than what I heard. (BTW, only could try the CDP -Zu Varial IC- as this was a A versus B test). I love my Gryphon but, anyone willing to wait for a half-hour's warm-up, well sir, lady, do I ever have a tip for you!!!!
Underscore: Till now I had no clue as to how good my Promitheus TVC & Active Tube Gain Stage was, is. This sounds like a platitude: in the right chain, they'll move you and give you more than you've ever dared dream for. Thanks AC for this forum, thanks Nick, thanks Scott & A-S and thanks AudioBear!
