RCA versus XLR interconnects

ghdprentice

... I find the quality of the interconnects are more important than whether they are single ended or balanced. Balanced are a bit louder… but this difference is not likely to net you a performance gain.

It really depends on the design of the equipment. For differentially balanced components that are AES48 compliant, there should be no volume difference between single-ended and balanced. But many differentially balanced components do not observe the AES48 standard, such as most (if not all) ARC amplifiers. In that case, you get 6 dB more gain using the balanced connection. Or, if you prefer, you can look at it as a 6dB improvement in S/N.

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.  

eylai777

... To have a truly balanced component, it needs to have 2 completely identical circuits that are out of phase (full deferential) ...

That isn’t really correct and the guy who told you that doesn’t know how op-amps work.

OCD HiFi Guy also said true balanced components do not have RCA connectors, only XLR.

OCD HiFi guy is completely wrong. It isn’t the connector that establishes whether an amplifier is differentially balanced, it’s the circuitry. As an example, consider ARC’s series of Reference Phono preamps. Fully differentially balanced; inputs are RCAs only.

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. 

all my electronics are Ayre....differentially balanced...hace all xlr cables including phono input....dead quiet even at full volume.