Favorite one box C.D.??

Naim....nothing more musical that I've heard in a one-box. I have a CD5 with a HiCap (guess that makes it two-boxes, but I do like it fine with one) which is a very smooth and engaging player. I'd also look at the CDX as wellas the CD2. All have a reputation for being very musical one-box players. Have heard both the latter and would highly recommend them too. Don't need the external power supply, but it does make an improvement. Naim started supplying the newer players with optional RCA outputs. Otherwise you may be limited to conversion or use with Naim 5-pin DIN interconnects (Chord makes some good ones, and you can get Naim to build one for you that goes to RCA if you provide the RCA cables). Not enough to warrant the new price of one IMO. Used perhaps. Check the comments and reviews online from owners and reviewers both.

Marco

PS Haven't heard the AA the Unclejeff mentions but it has a GREAT reputation as well.

Of the ones I've heard, the AudioMeca Keopps, as a bargain unit, and the Linn Sondek CD 12, at the top end of the spectrum, are the ones that have stood out from the crowd. The Linn really is as good as it's cracked up to be, in my opinion.

Ayre CX-7.
Had a vinyl friend(not literally) visit recently-commented the best digital sound he'd ever heard.

I have owned two of the players on your list, the Cary 306/200 and currently the Audiomeca Mephisto 11.X. I found the Cary an excellent cdp but wanted to go to the next level. I auditioned the Audio Aero Captiole and found it exceptional but was concerened about built quality and somewhat confusion on my part about all the upgrades available on a new model. I finally decided on an Audiomeca Mephisto 11.X and couldn't be more pleased. It is one of the most musical cdp I have heard, the frequency extremes are extended and the midrange is liquid and transparent. Good luck.

How about a BAT with Amperex 7308's and Symposium Rollerblocks