Hello all - I haven't read through the latest flurry of posts in detail, but
@_Alchemist_ I have some experience with many of the questions you raised so I'll throw in my $.02.
Totally agree with
@eagle3333 that Essence is an altogether different level of transparency over Diablo 300, but this will probably make the Essence more sensitive to the rest of the reproduction chain, recording quality, your room and tastes, etc. Also I will caution that it is so neutral that if you are expecting the trademark Gryphon "dark chocolate" richness, you may be slightly disappointed. By my best assessment it is really very close to DEAD neutral, and as such is less tonally warm than the Diablo 300 (though simultaneously sweeter and less harsh/more effortless at volume). And while
@eagle3333 has gotten the best bass ever from his Mojo speakers, on my Audiovectors I think the Diablo 300 has a more powerful bottom end. The Essence bass is extraordinary in quality but not as gut-punching, and on the SR 6 it is a bit light vs. the Pass XA30.5 or a Class D amp I am currently auditioning (ICEdge 1200AS2). Listening to something like Billie Eilish, again with the caveat that this is in my room and system, the Class D amp does better the Essence in sheer visceral punch. Pretty much everything else goes to the Essence as expected, including dynamics despite it being a "50 watt" amp vs. the Class D's 600W+ rating. (It helps that the Audiovectors are 92dB efficient.)
Given above and the big price jump, I would definitely try to do some further research before pulling the trigger on the Essence over the Diablo for a speaker like the Magico A3 which is on the lean and precise side already. I actually know someone who has the A3 and just got the Diablo after trying many different separates (last one was a Krell amp with ARC pre) as well as Audiovector, Focal and other speakers. If you like I can ask him how he's liking the Diablo.
With those caveats noted, I can definitely confirm that the Essence amp is an exquisite piece that will likely get you as close to the music as anything you can buy anywhere near the price. It has that immediate, tactile quality that some of the best megabuck systems I've heard sometimes achieve. The last time I heard resolution like this was in a decked-out MSB Reference + Magico M3 system - yes, the DAC was vastly superior to mine but I think the Essence part of the chain was on par in resolution. Ears I trust tell me the Essence reveals some details that no other Gryphon can, even Mephisto. And it does this without ever sounding the least bit clinical. (Make sure you give it a good power cord though!)
Re: the Zena DAC module, I'm a bit torn as it's obviously "very nice kit" as the Brits like to say and you can clearly hear the quality of the Gryphon implementation - battery-buffered USB supply, Class A analog stages, etc. - but there's just something about most Sabre DACs that doesn't quite click for me. It's a very good match to the preamp and a good choice if you want to set it and forget it, but I do still prefer my PS Audio DirectStream DAC by a hair for most recordings, just to give you a sense of the performance level (obviously there are even better DACs than the DirectStream). Sure, I would take the Zena over things like Benchmark, Mytek, Aurender around the $2-4k price point. I think the RME ADI-2 DAC FS comes pretty close for a lot less money, and I would definitely take, say, a Merging (yes I know it's Sabre but I love it) or MSB or Chord DAVE over it. (I have no experience with the NOS DACs like Lampizator, Holo that are all the rage.) So I think it just depends on how crazy a level of refinement you're looking for.
I have a review of all this coming soon on the blog, much overdue due to life stuff and general COVID malaise (sorry Philip!). I will let y'all know when it's posted. Hope this helps in the meantime!
(
@eagle3333 hope you and your partner have been well!)