RCA vs XLR

I prefer XLR vastly over RCA primarily because it offers the possibility of operating with balanced lines. The risk of interference is so greatly reduced that it's the standard in professional audio: microphones, mixing consoles, equalizers, signal processors, tape and disk recorders, etc., all have XLRs and have for decades. XLRs are also mechanically robust and have a locking mechanism.

RCAs are small, relatively inexpensive and convenient, but that's about all that I can say in their favor.

No connector should have a "sound." No connector should audibly affect the audio signal. If it does, it's defective.

I also like XLRs because you can buy great balanced cables from studio supply houses for a fraction of what typical unbalanced cables cost from hi-fi boutiques.

Many variables here. If the component is not "truly" balanced, the XLR capabilities are sometimes realized in a compromised fashion (I am told), which could yield inferior sound. In my system, balanced between some components is louder. When overall system gain is higher, perceived sonics can change due to how you have to set your pre-amp, etc.

Balanced inputs:
An amplifier which preserves separate, symmetrical amplification of both inverting and non-inverting input signals.

A "truly balanced" circuitry achieves the maximum sonic advantages of balanced operation:
common mode noise rejection (CMRR)
and cancellation of nonlinearities throughout the amplification chain.

This being the technical explanation. Theoretically XLR should give best results.

Rest is left to ones ears. Listen and you will know the difference.

Thanks Brauser for your sensible post. XLR against RCA is neither a matter of faith nor of simple specs and "science" generalised. The proof lies in the listening! At least that has been my experience too. An afterthought: Balanced power lines, be it through Equitechs or the PS Audio Power Plants, I personally found a true revelation in the general lowering of the noise floor. Got nothing to do with the topic of this thread, was just thinking about "balanced".

In a truly controlled (lab) environment with unlimited
budget design XLR will be better. Real world it isn't that
easy with some maufacturer's RCA sounding better than some
other's XLR. Even if it means spending a bit more, always
test your targeted componet in your room with what other epuipment it'll be connected to. Let your ears and taste
make the final decision.
it's going to be connected to

Ideally, neither XLR or RCA plugs should have a characteristic "sound". Pro audio types use XLR because of its relative immunity to RF contamination and its locking connection. In a low RF environment it's possible that single-ended RCA connections may sound better than balanced XLRs. This is due to the fact that truly balanced equipment requires a much more complex circuit design and implementation. In other words, it's easier to screw up a balanced design than a single-ended component. That's in theory, in practice it may be just the opposite. I use balanced XLRs, but then again I live in a high RF area. Your dealer is at the very least overly simplifying the issue.

Sounds like you ran across one of those people who think Single Ended is the only way to do audio. I am in total agreement with the fact that this guy is wrong -- how can RCA image better when XLR typically has 3-6 dB lower noise floor as compared to RCA???

Yeah, right. RCAs sound better than XLRs. That one ranks right up there with Pioneer's claim in the late 70s that their engineers had developed a tonearm that was lighter in weight but higher in mass. Maybe all the recording studios and broadcasting facilities in the world have missed the boat, and should immediately switch to using RCA connectors on all their cables. Now we finally know why recordings never, ever really sound like live music. It's those damned XLR connectors on the microphone cables.

Elgordo is right. Find a new dealer. What a joke...............................
"RCA connections will tend to sound more 3 dimensional that XLR".
I will put this on the top 10 list of the dumbest things we've ever heard a dealer say.
If people wonder why so many (hifi) consumers are so confused there is a prime example (dumb dishonest & usually disorganized dealers).
Yes, Avguygeorge, we find that TRUE balance usually (not always) sounds best, but many components aren't balanced, they just have XLR's (FYI for Jeffmazen).

You need to find a new dealer.

I'm generalizing,but most equipment only sounds best if you are balanced from source to amp.This refers to true balanced operation. Some pieces have bal,in or out for convience only.