The reviewer's words,
"I recently reviewed another class-A power amplifier, the Plinius Reference A-150 ($13,000). I characterized this sweet New Zealand amp as having “feathery highs, strong but round bass, [and] a midband of tonal density to die for.” The Essence had some of those qualities, as well as some quite different ones. Starting with those “feathery highs” -- much like the Plinius A-150, the Gryphon Essence won’t ever have you lunging for the volume control to turn down screechy highs. The Gryphon had poise in the upper frequencies -- its reproduction of detail sounded natural, without calling attention to itself. Much like the Plinius’s, the Gryphon’s midrange was tonally dense, something that’s long been a hallmark of Gryphon amps.
But the biggest difference was in the bass. Whereas the Plinius possesses what I described as “round bass,” the Gryphon’s bass was tighter and more physically present. Although Gryphon’s larger, more expensive Antileon Evo and Mephisto amps are even more impressive in just this way, if only slightly, in this area the Essence still has an advantage over most other power amps -- including the Plinius A-150."
He is saying that the Essence has some of the qualities of the sweet Plinius--"feathery highs, tonally dense midrange, lack of screechy highs." These are the words used by lovers of euphonic tube and some SS amps. "Feathery" highs means delicate, but lacking in sparkle. "Tonally dense midrange" means rich and creamy due to rolled off HF so that the midrange is emphasized. When I have heard dynamic speakers with amps described like this, the sound is dull boredom. These writers hate sparkle and brilliance, so they call it screechy instead.
The next problem with this reviewer is that he doesn't know that amps that have rounded bass, also have rounded midrange and HF. Electrons don't respond differently in different freq ranges. Tube and euphonic SS amps have this rounded character in the entire range. So if he is describing the Essence as having tighter bass than the Plinius, it is likely that the midrange and HF also are more defined than the Plinius. He is either a poor writer (I doubt it) or more likely, doesn't know how to judge sound objectively.
WC may have somewhat different tastes than me, but he knows how to describe sound objectively and truthfully, and he is building a reputation as a trusted reviewer with the videos to prove it. One day soon, he will A/B the Essence and Mephisto at home, and we will know the true story. Meanwhile, from this review, we have no way of knowing whether the Essence is like the somewhat euphonic Luxman, or whether it is more like the brilliant and transparent Mephisto.