Thank very much Audioenophile and reuben3. That’s pretty much what I was hoping.
Must… pulll… the… trigger…
Ok, I put my Qutest back in my desktop setup to do an A-B comparison with the DX340. I wanted to avoid bringing in too many other variables, like interconnects, so I just compared the following:
A. PC>Qutest (Chord USB cable)>Tsuranagi V2 Amp (Wireworld Nano Silver mini to RCA)>APX SE
B. PC>DX340 (Astell & Kern USB cable)>APX SE
In the above setups, the tonalities are definitely in the same section of the flavor menu.

I would call this section of the menu, "Vibrant & Resolving". Both have fantastic clarity, resolving power, imaging skills and big soundstage.
Qutest is a little more neutral and a bit less dynamic. Bass is tighter and a bit leaner and more precise, but there's plenty of slam. Acoustic bass & guitar notes aren't quite as full and don't have as much decay, but they sound very realistic. They may sound even more realistic since the notes have absolutely zero bloat. Horns & piano notes have a sweetness to them, with nice note weight, but I want more note decay, especially with piano. Female vocals can become a little sibilant at moments. Highs are a little brighter, but not in an unappealing way at all (this is also a new mini jack to RCA cable). Soundstage is really big and wide, instruments have lots of separation and air. This is a really beautiful combo. Some might say this combo is a bit drier. For me that means that I wouldn't describe it as liquid or honeyed.
DX340 immediately has a more holographic soundstage, bass is big and full, yet still pretty tight, and is more dynamic. It digs deeper into the bass, yet doesn't become bloated, but it is definitely beefier, bolder and richer. I am not left wanting more bass, nor do I wish it were tighter or leaner. The bass is pretty spot on for my music preferences and taste. Vocals are more forward and silky sweet, never sibilant. There's definitely a liquid quality to vocals and instruments. Guitar, piano and horns sound very realistic and the note decay extends beautifully, especially guitar strums. Overall I would say the DX340 has better harmonics. Upright bass notes are full-bodied and have great decay as well. It's dynamic, full-bodied and rich, but somehow it does not lose the vibrant qualities that I desire. It's all there from top to bottom, with a sweetness and liquidity that is addictive. There's almost an effervescence to its presentation.
Put the 340 in super gain mode (w/12-V DC cable), and everything becomes bigger & grander, the soundstage, in particular. Bass is bigger, but not bloated. The presentation here is just amazing. Female vocals make my mouth water. Male vocals and horns become fuller. Highs are still just as shimmery, but the notes float in air longer. Just stunning harmonics.
WORDS THAT I WOULD NOT USE to describe either of these setups: thick, warm, fatiguing, harsh, brittle, clouded, bloated