Balanced to RCA adaptors


I have a system using all XLR cables, and recently ordered a new preamp that is all RCA. (No choice here)
I am wondering, should I switch all my IC's to RCA, or can I just use the XLR to RCA Cardas adaptors and not have a sound degredation? If I do use the adaptors, do I need to use them at both ends of the IC or can I leave the amp end plugged in with XLR and the preamp end plugged in using the adaptor, to the RCA connection?
bullot
I'd avoid the adapters, if I could, but you've already got great advice on the options. Just make sure, if you get adapters, that they are worth a damn. I have a nice system and used a set for back channels (due to a temporary cable "changing of the guard") I pulled apart one of the adapters. It was a generic one sold here on Agon and was appallingly poorly made, horrific wire and cold soldered. It looked good on the outside, though. I guess it would serve the purpose, but you have nice gear. I would always have that suspicion that things weren't quite up to snuff, so if you do go with adaptors, get good ones with a return/inspection policy behind them.
I think we all agree that if the adaptors can be avoided, then do so........that is the direction I am going to go. As Jeffb said, I would alway be suspicious that the system is in some way not up to snuff. I will move to RCA and use the adaptors only as needed untill the RCA swap is complete. Thanks to everyone for their feedback!!
I have tried the Cardas adaptors and the BAT to run from my unbalanced Wyetech Opal pre to balanced Krell FPB 300cx. Both are very good but the BAT's, though more expensive, are better. I think Music Direct sells them.

Neal
this is from the manual of the 33h

Note
Before making balanced connections, remove the U-shaped
shorting-strap between pins 1 and 3 on the Nº33H XLR input
and save it for possible future use. This shorting-strap is
installed when the Nº33H is shipped.
4. single-ended input
Receives unbalanced audio input from a preamplifier with single-
ended outputs. These signals are converted to balanced signals
upon entering the chassis and processed as balanced signals
thereafter. One RCA connector is available.
If the associated preamplifier does not support balanced
connections, connect the RCA output on the preamplifier to
the RCA input on the Nº33H. To reduce the chance of noise at
the (otherwise unterminated) inverting XLR input, insert the
supplied U-shaped shorting strap between pins 1 and 3. (This
shorting strap is installed when the Nº33H is shipped.)
"...Receives unbalanced audio input from a preamplifier with single-ended outputs. These signals are converted to balanced signals upon entering the chassis and processed as balanced signals thereafter."

Most probably, this amplifier uses phase splitter to process unbalanced audio inputs as balanced signal thereafter.

As far as I know, Joule-Electra LA-300/150 single-ended preamps use this technology processing all input single ended signals (RCA) in balanced mode i.e. canceling preamp induced distortions and reducing the noise and before output converting these signals back to single ended in order to exploit RCA outputs.

This is very clever approach allowing these preamps to do balanced processing "on the cheap". Indeed, this is could be one of the explanations of why LA-300 is so quit (more quit then most ss preamp I auditioned) with so much "black background" making music so much more realistic.

Thank you
Rafael