XLR-RCA adapters - which to choose?


I need an RCA male to XLR male adapter because my SACD player doesn't have balanced outputs and I don't want to reterminate my (expensive) Nirvana S-X Ltd interconnects! Does anyone have a view on who makes the best and/or best value adapters? I have been considering Purist Audio Design (expensive) and Cardas (less expensive). Is there much differnce between them and are ther others I should look at? Thanks
jabali_hunter
Thanks for all the suggestions. It seems that most people are pretty happy with the Cardas adapters. I noticed some darkening to the sound when using an unbalanced cable terminated RCA to XLR. I put it down to feeding the balanced inputs of my pre-amp with an unbalanced signal, so maybe all adapters would have the same effect. Otherwise it was just crap cable!
Nelson Pass suggested I use the item in the link below. It ain't cheap at $200 per stereo pair.

Check it out at the link below:

http://www.jensentransformers.com/pc2xr.html
Wow - that is a serious looking piece of kit that Mitch4t suggested! For $200 I could reterminate my balanced S-X Ltd to RCA and then back again later if I change my source! I take it there is a real advantage to getting the Jensen transformer?
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We bought ours from member infinity_audio here on Audiogon.
Around $40, and they work great.