Hi Artg,
I own an Audio Aero Capitole MKII cd player with the SE upgrade on the output stage and I have to say that in my experience it is definitely the most analog sounding digital player on the market. Forget DCS and Meitner, they're both good but not nearly as analog sounding as the AA player that you have, though it all depends on personal preference. I know of only one person that's sold his AA Capitole MKII without regrets and went with an APL 3910 which he also likes very much.
Although the AA player is very good right off the bat, I can tell you from my own experience that it will sound much more alive and more detailed with a soundstage at least equal to your ML 390-S if you replace the AA's isolation feet with symposium rollerblock series 2+ in double stacked configuration with the grade 3 tungsten balls (not the regular grade 10 balls that come standard). You can also use the SRA Ohio XL base as an alternative, a very good isolation platform and probably more convenient to use since you don't have any rolling parts. Hearing is believing; you will never go back to the old feet once you try the symposium rollerblocks.
Also, by far the best powercord out there for this player is the Shunyata Anaconda VX. I've tried the top of the line Elrod and Electraglide pc's and they cannot match the Anaconda, although they do provide more speed. Shunyata is the only way to go with this player, but the Anaconda VX takes about 2 weeks for the FeSi to fully settle in, even if it's already fully broken in. If you want the same sound with more bass, then I'm told Transparent Audio's top of the line pc is the way to go.
Lastly, if you have already spent all this $$$ to bring your system to where it is today, but are looking for further improvement ... I can also recommend the Whest Audio DAP.10u which I have introduced into my system recently and ... WOW! Unbelievable difference in overall sound, from top to bottom. Whest Audio has made a believer out of me. I also use a set of Symposium rollerblocks series 2+ here as well with a Revelation Audio Labs PRECEPT powercord (also a good powercord, very close to the Shunyata Anaconda alpha, but for amps probably not the best out there, Elrod and Electraglide should be considered here as well).
One more thing, the SE version takes 1800 hours to fully break in, and don't turn it off, that way it sounds best.
Anyways good luck and happy listening. "Fly to the music"
