Does something like that exists? A player that can delivery enough seperation for all 7,8 instruments to sound clearly at the same time.
If the rest of your system allows it to, yes. If it's revealing, unyieldingly analytical you're looking for, you might get better results with suggestions for an entire system, rather than just the CD player. Because even the most revealing CD player will be censored by speakers that are not so...and most aren't, IMO.
As for CD player, I think these fit your description:
Wadia
Ayre
Meridian
MBL
EMM Labs
The rest of the chain should follow in kind, if that's the sound you're wanting. If you decide you want such input, please tell us the size of the room, music preferences, full range/monitors, SS or tubes, access to dealers for auditions, etc.