I have used single ended for the last fifty years. I have monitored reviews and forums on the subject... and specifically reviews on my Audio Reseach Reference gear... Phonostage, preamp, DAC, and amp RE160s. ARC equipment is balanced internally, and XLR is recommended. Most reviews notice a slightly better sound to the XLR. There has been a slow shift to XLR being noted as better across the industry. While not night and day... pretty consistently. XLR provides a louder signal, making it hard to compare with RCA. I spent hundreds of hours comparing different interconnects in the 80’s and 90’s... so I can read reviews and understand what they are saying and put it in context. I have a really good system, and am not going to waste time doing any more comparisons (especially since break-in is important and long for interconnects) So, I have been slowly swapping out my single ended for XLR... they are $4K per pop, I have one left. If I was starting today I would go XLR.
Also, as noted above it is recommended for long runs. I also have my equipment off to the side. Locating the equipment off to the side probably has a bigger impact than RCA vs XLR in short lengths, But they are all additive, so every little positive thing adds up. If you want a truly great system you want to optimize all the small stuff as well as big stuff.
Also, as noted above it is recommended for long runs. I also have my equipment off to the side. Locating the equipment off to the side probably has a bigger impact than RCA vs XLR in short lengths, But they are all additive, so every little positive thing adds up. If you want a truly great system you want to optimize all the small stuff as well as big stuff.