RCA versus XLR interconnects

For what it’s worth, MacIntosh technical advisor said he would use XLR over RCA all the time regardless of the length because of RF interference. 

https://www.youtube.com/watch?v=tPBitFrmlzo

The video was very helpful. To have a truly balanced component, it needs to have 2 completely identical circuits that are out of phase (full deferential). OCD HiFi Guy also said true balanced components do not have RCA connectors, only XLR. 

My source is an Eversolo DMP-A6 which at $850 most likely is not balanced even though it has XLR outputs. My preamp and amp are MacIntosh C2300 and MC 302. While they are more expensive, I am doubtful they are fully deferential, and they both have RCA connectors. 

I will, however, call the companies and report back. At the end of the day, it doesn't sound like XLR versus RCA for my system will make a significant difference.  

Got a amazingly fast reply from MacIntosh:

"The 2300 preamplifier circuitry, XLR’s are converted from bal-unbal on the way in and unbal-bal on the way out.

Converting involves a single op-Amp of added circuitry. While added circuitry does add noise to a signal,

XLR connections cancel any noise induced along the cable, which will be infinitely more than the noise created by the single op amp.

The MC302 Amp is differential."

IMO, purists would probably only accept full differential with identical circuits. Op-Amp converts to a balance signal on the way out but does not preserve balance circuitry in the component. In any case, except for the uber high-end (which is not my system), it probably doesn't make much of a difference except of some DB gain for XLR's. @ghdprentice advice that the quality of the interconnect matters more than whether it's XLR versus RCA makes sense, at least at my level. 

I promised to report back, and here's the reply from Eversolo:

Question:

I have an Eversolo DMP-A6 DAC/Streamer.

It has XLR outputs, but I want to know whether the circuitry inside the unit is fully deferential?  In other words, two completely identical circuits out of phase to minimize distortion

Answer:

Regarding the issue, the answer is yes.

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Seems like this budget $850 DAC/Streamer has a full differential circuitry but Jay Iyagi (https://www.youtube.com/watch?v=ESZxMDxapm0) suggests it's Op-amp. One can only verify by opening the unit up which I'm not going to do so since it's under warranty. 

You’re probably right but I really don’t want to get too much into it either. 
 

If I have a decent system and tried my best to maximize it (without spending too much time), that’s good enough for me. Rest is for the forum community. Someone may find these posts helpful.