Pale Rider, thanks for clarifying. I certainly didn't get that the first time around, sorry. No wonder I was surprised about it. I mean, I used to think IC's were primary in all this chain, maybe only second to power treatment. With your statement in the right context, I feel now my speaker cables are decent enough not to be a critical bottleneck, and although these could be improved, of course, I may need more of other essentials before upgrading speaker wires, like Herbie's aids. No doubt power could certainly be improved but again, I'm not totally uncovered in this area either. Experimentation with the isolation gadgets first may give us some clues.
Will, your analysis is quite sensible. It is hard for me to answer your vital question, though. I may not be able to identify what exactly is missing without being exposed to those virtues, first hand (reference). I know the sound can be improved (as I notice it quite easily just by switching music sources that are recorded differently). Then there's the never-ending, compounded break-in period uncertainty in my new gear. Who can tell what would be the final sound on this setup, eventually? I certainly cannot at this point.
Having said all that, I feel more soundstage and transparency may be wellcome. Whether this impression is due to the break-in or not, it definitely is something I feel is still lacking.
On the isolation transformer, yes it definitely performs two essential functions: Prevents surges and limits noise coming from the mains. As far as I can tell, the Tripp Lite is working without contributing with its own noise. My speakers are normally dead silent even with my ears very close to the speaker screens, and silence between selections is absolute, so I do not suffer from apparent humming noises either.
I hear you on the isocup feet, as well as those dampers, and certainly could try the Baby Booties, as these all seem cost-effective to me too, especially considering your collective positive sound improvement impressions.
Concerning the ZStage, I just don't know what should be first. Maybe you guys can lead me into interpreting what I just mentioned about soundstage and transparency. Now, to be clear, when I stream a very well recorded source, details abound, and the transparency is there, not so much the size of the soundstage. So maybe the clue for you guys to interpret this is soundstage limitations only? When the recorded material is suboptimal, though, I have some difficulty separating some frequencies and the music seems to be a little under a 'veil' or maybe coming from a closed container or something.
The potential of this gear definitely shows up with well recorded material, naturally, but the key here would be to extend some of that potential to the bulk of recordings. Whether break-in, lacking isolation, power nuances, inefficient cabling or foregone benefits of a ZStage is what I could not pinpoint. Maybe you have a better idea about it.
Finally, as you put it very well, we have not even discussed tubes. I was under the impression tubes may change colors, tones and timbres, but not sound quality per se. I think what I'm missing relates more to essentials than to these rather more esoteric shades of playback sound.
In the end, a better USB/DAC may be the answer, but I suspect it to be still far up in the evolution yet, as it would not compensate for essentials missing. So I'm almost back to block one, except for the isolation devices. BTW, are dampers for the output tubes only (or maybe also the drivers)?
Will, I see you are inclined to suggest the ZStage, assuming no major essential drawbacks. I give you my earlier sound evaluation for you to maybe confirm or discard that statement. Thanks again for your insights and patience.