I haven’t observed any weaknesses yet to my ears. Is it perfect? I’m not sure one exists. It capably performs and is versatile. Does it exceed the sonic ceiling of my LTA MZ2 with select tubes? Not for me, but the Jot 2 is a winner, and I look forward to continuing to own it.
The biggest difference to date between the MZ2 and Jot 2 is that the former has more holography and depth to the stage, larger sonic images, more micro-detail, greater focus and resolution. Such should not be a surprise given tube vs solid state, and the ZOTL design/circuit even against other tube amps (push pull vs single ended, among other things).
If pressed to quantify how much of the way the Jot 2 gets to my MZ2 with select tubes (RCA 6SN7GT VT-231 military blackplate grey glass and Telefunken 12AT7), it’s somewhere between 60 and 85 percent. I might be a tough or easy grader though. The MZ2 with tubes also costs more than 4x. For reference, I don’t think the MZ2 is the last word and I intend to complement it with a Class A single ended triode tube rectified no feedback amp, similar to your DNA or ampsandsound as you know.
I believe the toobish is associated with the division of the differential output and resulting distortion. Per Jason on head-fi:
And some people will note that the single-ended outputs don’t measure as well as the balanced outputs. Yeppers, 100% right. That’s what happens when you use one phase of a balanced output and lose all the distortion cancellation from a differential topology.
Aside: it also gives you a distortion profile that’s reminiscent of a tube amp. Hmmmmmmmmmm….
But is this a bug or a feature? Maybe the single-ended output sounds a bit softer and tubier because of its distortion profile. Or maybe all distortion is sufficiently below the transducer distortion that you can’t hear it at all, in which case the argument is moot. Or maybe most people choosing a differential amp will typically be using it with balanced headphones, and the single-ended output is a convenience.
In any case, this is literally the same approach we took with the original Jotunheim, and the approach we used in Ragnarok, and the approach we used in Magnius, because that’s what our customers said they preferred—using one half of the differential output, rather than summing to single-ended.