Can a direct CD to amp connection degrade sound?


I've had a Cary 300/200 for over a year and always ran it thru my Rogue 99 pre amp. A week ago I tried going CD to my Rogue Zeus amp direct. Many ads suggested that with a volume-control CDP, a pre was a waste. Sounded right on paper, sounded very wrong in person. The sound without the pre was flat,tinny. There was no air around instruments. What happened? How can a pre improve a CDP's signal when the whole point is to leave the signal unchanged? Has anyone tried it both ways and compared the results?
manorraul
of coarse a good preamp is better. only use direct if you have no preamp otherwise why would they make preamps??????? also volume controll on a cd player is best at full volume
Throughout the years, I've seen more negative than positive comments when people go directly from the CD player to the amp.
I am running an Art Audio PX-25 direct to a Audio Aero Capitole MK2 and it sounds better in my system then it did with a BAT VK50SE!!!!! You have to listen to it in your system and let your ears be the judge--------
I have tried a couple pre-amps with my GNSC modded Wadia 850, and never found anything that gave a significant improvement. Most take something away. Even when I felt like there was an improvement in some parameter, there was more lost in other parameters that made it a net loss. IMO
Neither unit mentions impedance so I assume all you can do is try. The Cary can be set for a lower output voltage and I may try that. Anyway, thanks for the education