Is there advantage to balanced phono-preamp

^^ just a point of clarification, if the circuit is differential (a form of balanced operation) then the 'plus and minus portions of the signal' are handled by circuits that are **not** 'completely separate', in fact the circuits must be intimately connected to each other to create the differential operation.

A nice advantage of balanced operation with phono is the fact that the interconnect cable need no longer impose a sonic artifact on the signal. If you've ever heard of someone paying $1K for a phono cable, you know what I mean. The balanced line system was created to eliminate interconnect cable artifact and this **really** works out well with phono cartridges, since imposing artifact that that point would be at the earliest point in the system!

FWIW we make a variety of inexpensive (since balanced operation eliminates cable artifact, they don't have to be expensive anymore) balanced cables for phono use. We were the first manufacturer anywhere to use balanced inputs for phono operation.

Plus, you can put your table 200 feet away from the preamp.  

lewm

 "CLeeds, Please note that I used the word "usually" when describing the cable needed.  You've pointed out the cases where one would do other than the usual."

Oh yes, duly noted. Fair enough.

" The user should beware of using an RCA-terminated IC for balanced phono, since in that case it is possible that one half of the signal, which for convenience we can call the negative phase, is being carried on the cable shield.  (There is no "neutral" in the balanced mode.) That is a compromise I would not care to make. "

Agreed!

" Are you sure that ARC phono stages that purport to be truly balanced use RCA input jacks?"

Yes, absolutely.

czarivey "The signal from phono cartridge actually comes BALANCED.
Each channel has +, - and ground.
all you need to do is separate ground between 2 XLR connectors."

There's nothing magical about XLR connectors. You can maintain balanced operation by using RCA connectors, but you must keep the ground separate from the neutral or - as others have also pointed out - more correctly the opposite phase signal.

I use and recommend the Ayre P-5xe mp phono preamp. Its not worth it unless your whole chain is balanced. Moon-audio & Grover Huffman can  make custom cables for mini din to xlr. You can download the manual for the Ayre  and see schematics for acceptable cable wiring. I like to use the shortest and smallest gauge wires with good shielding for phono cables.