SQ difference XLR vs RCA ?

RCA and XLR can be implemented differently.   I think your question assumes that they are the same signal sent through RCA wires or XLR wires.  But XLR can be implemented different ways.  Often a small transformer is used in the XLR input.  This will change SQ, maybe better, maybe worse.  It may pair well with your preamp, it may not.  So implementation methods of XLR may make your question more complicated than you meant and answerers may not realize how their xlr is implemented.

In my amp, Decware, it is hard to compare.  The XLR amps have a transformer that adds about 8dB of gain.  so you have to adjust volume to try to do an A/B. Right now Im using XLR.  However, I've upgraded my RCA connectors coming out of the amp and may go back and forth.  I don't have a strong opinion.

@mabonn,

SQ difference XLR vs RCA ?

See article below:

Mike

http://www.atma-sphere.com/en/resource-why-balanced.html

no, most likely

My question is this:  if I have a quiet system with short runs, do balanced connections sound better?

They should not sound worse.

As the noise increases, and the runs get longer, the balanced stays better for longer.

Basically:

• If it sounds good now, then do not change it.
• If you are looking at an equipment change, which is more immune to noise, then balanced helps.

No. The difference is incredibly subtle and contingent on your specific components and length of run (if dozens of feet). When you get to own the best system you have ever imagined… then bring this issue up again. For now, rca will do the job and cost less.