Comparing Perf: Original XLR v. RCA- XLR adapter

Lall

I would be grateful for feedback on any potential performance difference between an original Balanced (XLR) high end Interconnect (e.g. Kubala Sosna Emotion) and the same cable originally RCA ended but fitted with high quality XLR adapters to meet the needs of balanced gears (preamps and amps) with no RCA options. The entire system is high end.

Rather depends on the adapters. Many of them tie pin 3 to pin 1, attempting to turn the output or input into an unbalanced one. If you can find an adapter that only ties the RCA to pins 2 and 3 it can work well, especially if the cable is symmetrical and unshielded.

Nsgarch

1. Balanced cables are only "quieter" if carrying a balanced signal (a plus and a minus referenced to a neutral conductor) in which case noise in the normal (non-inverted) signal cancels with the noise in the inverted signal -- this is known as common mode rejection. So if, via an adaptor, one sends a single ended signal ONLY (in other words, half of a balanced signal) through a balanced cable, common mode rejection doesn't come into play. So there goes the noise rejection advantage.

I'm afraid that's incorrect.

Balanced interfaces and the common-mode rejection that they offer have nothing to do with the signal. A balanced interface rejects common-mode noise even when there is no signal present, and it doesn't matter whether the signal's being sent asymmetrically on one line, or symmetrically between both lines.

What "balanced" refers to is the impedance of each line with respect to ground. The source impedances must be balanced in order for the differential input to be most effective at rejecting common-mode noise. Any imbalance will degrade this rejection.

Nsgarch

Everything _q says is wrong.

No, it's not. You're simply repeating one of the most common myths about balanced interfaces because you don't understand how they work.

For those who would like to inform themselves on how balanced interfaces work, this is helpful.

Answers to Common Questions About Audio Tansformers