Using XLR to Rca adapter

I used those just as you are contemplating (Cardas brand) and it introduced pronounced noise into my system. I could hear the transport motor! I put them away and still have them....I would stick with the rca to rca interface.

Properly run, RCA will equal XLR. The purpose of XLR is for long runs with multiple adjacent lines- AC, Speaker level, antenna, other ICs, as in studios. I have runs of RCA that are 25 feet in length using a variety of shielded single ended RCA. Absolutely no noise or audible interference to my ear. In runs behind components, short shielded and unshielded RCAs are likewise free of audible noise. Make sure the ICs are properly designed and built for your purpose. In my system, the long runs are necessarily close to other wires and thus I use braided shielded designs. I have no RFI issues where I live and I try to control EMI at the source using shielded AC cables, physical distance, and ERS cloth. I have other ICs that are short and not near other lines and I use a variety of shielded and unshielded solid core and twisted ICs. Experiment with them, buy used, sell what you don't like, and most of all, have fun!

As has been indicated in the prior posts, using an adaptor to connect your system through the balanced inputs has no advantage and may actually be disadvantageous. For one, using the balanced inputs does not mean that the signal would be balanced since an adaptor will not convert your standard signal to a balanced one. You seem to be thinking that the adaptor will provide you with a shortcut to having a balanced system. It will not. Secondly, the fewer connections, the better. Adding yet another interface between the signal and your amplifier or preamp will more than likely increase noise, to say nothing
of adding to the likelihood of hum.

It's highly doubtful... but will sound no worse.

I have (2) sets of the Cardas XLR to RCA adapters running into my ARC preamp that have phono stages at the other end and I hear NO noise or any other anomolies. I ran out of RCA inputs, so I had to use the balanced inputs. My phono stages are RCA out only, so this works VERY well for me. I agree with Blindjim.