I am running a computer system from a Mac Pro using Pure Music software via digital optical toslink to a CEntrance DACmini and then directly to either the airmotiv4s or HiFiman HE-400 headphones. The toslink cable is ~a 6 ft. run, I have shielded but not otherwise out of the ordinary 1 meter unbalanced RCA interconnects from the DAC to the speakers and the stock HiFiman cable for the phones. Nothing fancy on the power for any of it, other than keeping the DC adapter from the DAC on the floor, thus distancing the AC line power. The speakers sit on my desk, no stands (they came with little stick-on rubber feet), about 3-4 ft distance to me and angled towards my chair (and head as well, usually).
As far as my take on some of the questions that have caught my attention, first I do not hear any detectable hiss from the speakers, although the Mac Pro provides a bit of background noise at all times (audible even through the open headphones). I came to this setup in an evolutionary way, starting with the Audioengine A2s and no DAC, which I found disappointing in most every way. I added the Audioengine D1 DAC which brought minimal improvement. As the A2s were still within their return period, and I was reading such good things about the airmotiv 4s, I decided to upgrade. The improvement was enormous, in just about every aspect of musical reproduction, but particularly so in bass reproduction, openness and sound stage, and clarity of the treble. Next step was to give the Audioengine DAV to my son as a birthday gift without mentioning that it was to enable me to upgrade the DAC to the CEntrance DACmini. Rock my world! The difference made by the DAC was remarkable, both through the speakers and the headphones. Most improved were the soundstage and separation, clarity of voicing, realism in the treble, and tightening up of the bass. The airmotivs seemed like a new speaker altogether, their realism paired with the new DAC was impressive. Finally, I added the Pure Music software, after also experimenting with Decibel, and the incremental improvement was again gratifying.
I now have a system that (to the dismay of my family) keeps me pretty near glued to my desk, trying to invent excuses to be there so I can listen without pause. I haven't enjoyed music like this in decades (corresponding to the birth of my children which meant the death of my living room HiFi setup).
So no, I haven't heard the Adam speakers which also piqued my interest but were too pricey for what seemed to be a similar product to the airmotivs, but I no longer feel the need to change the system any further. I am deriving such pleasure from this setup; I think my eternal GAS syndrome will be dormant for at least a few weeks (probably a duration record for me).
Thanks to all forum members who have made my lurking here so pleasurable and educational over the recent past.