RCA to balanced

The Cardas adapters connect pin 3 (the minus leg of the balanced signal) to pin 1 (ground). This turns the BAL input into a single ended input. No advantage and maybe some adverse effects.

", buy a true balanced phono stage to go with your balanced linestage." Or buy a single ended phono pre with an output transformer like the K&K Audio Maxed Out. Transformer coupling can provide a true "balanced" out.

"True, but then you are dealing with the limitations imposed by the transformer"
And the limitations of output coupling capacitors have no sonic consequences? Or OP amp buffers? Personally, I much prefer the "limitations" of a quality transformer to the other alternatives. But then I'm not in the business of selling OTL amps.

Nsgarth, the discussion here was line out transformers, not MC input transformers. Although even here good SUTs are very competitive. For example the new Lundahl silver LL1931AG at $800/unit. That's performance competitive, maybe not price competitive as OP amps cost a few dollars at most. FYI, SUTs supply gain. Capacitors do not. That requires active circuits. That means transistors or tubes or OP amps. All of which have there own issues.