I have gone from using RCA to XLR and back over the 40+ years of equipment/listening. I've stayed with RCA for the last 15 of those years even with 5-meter runs of interconnects from my preamps to the amps. While I definitely agree about CMMR with XLR, I believe if your system is clean and relatively noise-free, my experience is that RCA is a touch better. If you have really good RCA or single-ended vs. balanced (XLR) equipment, the mfg has put all the money into single path amplification of the signal. Even with extremely well spec'd balanced circuits, there are two active components each touching the + and - signals and in some cases even high precision component differences can result in slight sonic differences. In my experience, the least number of active components "touching" the signal will yield the cleanest signal. Now if you do choose balanced and XLR equipment, make sure your equipment is balanced through the unit input to output. If it's a single-ended device with XLR inputs or outputs, you're only going to get a single-ended input signal and output signal. No CMMR benefit !
SQ difference XLR vs RCA ?
I’ve read lots of the discussions on this forum about balanced vs single ended connections. My understanding so far is that balanced connection has better signal to noise than single ended, which helps if you have hum or noise problems or if you have long runs.
My question is this: if I have a quiet system with short runs, do balanced connections sound better?