I know this topic came up before, but this is my recent experience with this new cable I just got. There are a lot of you that think both outputs are about the same. I find there are considerable advantages with XLR. First, out of my DSS to my preamp, I compared using WW Platinum Eclipse 7’s, the XLR’s is a bit clearer and more detail sounding, but I had to adjust the level since RCA is 6db down. Today I just replaced a pair of Platinum Eclipse 7 RCA’s with a pair of Platinum Eclipse 8 XLR’s between preamp and power amp and WOW!!!, much clearer and more resolution. I know, I know, It might be the difference of the 7’s and 8’s. I don’t have a RCA 8’s to try, but my brother has and we will try that next time. I already try Platinum 7’s RCA and 8’s RCA between phono and preamp last time and did not find that much difference.
The WW Platinum Eclipse 7 is a phenomenal cable. It beat every cable I tried in the past including a pair of Tara Labs Zero’s which is $16k, the most expensive I tried. The Eclipse 8’s is even better.
But definitely, after hearing the XLR’s, I will never go back to RCA’s again, too much of a compromise.
Totally agree with you about XLR. Using XLR, I find that the cable has less influence on SQ then when using using RCA ended cables.
I’m very surprised there’s even a debate on this, XLR is far superior by design and basic electronic principles.
What they said.
Single ended design has vocal proponents. A couple who come to mind are Frank Van Alstine and Keith Herron. Herron has argued that fully differential circuit design increases complexity and cost unnecessarily for home audio applications. He has plenty of happy users of his gear who have voted with their pocketbooks. We’ve got to remember balanced design was conceived for pro audio applications where cable lengths can be long and circuitous and points for pickup of noise are … everywhere.
As always, it comes down to solid design and implementation.
I favor balanced operation for one reason, common mode noise rejection. I have a vinyl front end where that is particularly important.
One final point I make whenever this topic comes up: the fact a component has, say, XLR input/output connectors is not a guarantee the circuit itself is fully differential. Details, details … that’s one that sometimes gets overlooked by the high end audio consumer. When in doubt, verify with the manufacturer what you are getting.
This ^^…along with various system synergy factors associated with “implementation”.
The older I get, the less absolutes I hold on to. YMMV. 
I couldn’t agree more. There are complexities to this topic that must not be overlooked. And as @owlsalum mentioned, just because a component has XLR inputs/outputs, does not mean that it is truly balanced (fully differential).
Secondly, if you do not have a noise/interference issue in your listening environment, then unbalanced could be the better choice. Even good transformers such as Jensen’s are in the signal path. My interconnects (Harmonic Technology Photon cables) are immune to EMI/RFI (they use photon light rather than a metal conductor(s) for the signal). I have an RCA set and and XLR set. I compared them both in my fully differential system between my pre-amp and amp. In my system, the unbalanced connection sounded better.
I auditioned Iconoclast OFE both RCA and XLR and I thought the RCA’s sounded maybe a bit better.
@RonP
Could you elaborate on how the RCAs sounded compared to the XLRs?
It is as others mentioned. If the component is designed balanced through out, then it may be advantageous to use XLR. If the component is not designed balanced, then using RCA might be better.
what about the converters on both ends?
It is not the sort of thing that you can absolutely say, “One is always better than the other” IMO.
Ironically/coincidentally, I just put a much cheaper SE pre in my “A” system, and it is much more musical. I suspect it has to do with something other than SE vs. Bal.
And this is leaving aside the issue of whether everyone who actually compares A/B with matched volume ; )
maybe just a bit more vivid. but it’s been a while.
I just switched to balanced cables running from the SGCD to M700 amps and all I can say is WOW!!! The improvement is quite impressive! The refinement in vocals and string instruments has improved dramatically. I did my own A/B testing today against my vintage Conrad Johnson tube pre & power amps (which can only use single-ended rca connections), and while the tubes are a little more liquid and smoother sounding, with the xlr cables, the tonal qualities of the PS Audio are quite refined. Oh, and regarding the A/B testing, I was fully aware of which components were hooked up and did not perform any volume matching of any kind whatsoever.
What about them? If you provide more context to your question, I may be able to answer it in a meaningful manner.
I too have discovered the benefits of XLR in my system. I have a DS DAC and a Luxman M700u. I was using RCA from the DAC to Poweramp until I got my BHK Preamp. At that point I tried the XLR. There is a huge difference in both the configuration of XLR straight from the DAC to the amp and XLR from DAC to Pre to Poweramp. After using XLR in this system I will not go back to using RCA. I am currently using Gen 2 Iconoclast UPOCC XLR cables. I was using Gen 2 Iconoclast TPC RCA. If you have a chance to try Iconoclast do it. You won’t bother with anything else after that.
My brother’s came over with the WW Platinum Eclipse 8 RCA’s so I can compare it to my XLR’s and sorry to say, not much of a contest. From my preamp to the power amp, same volume, the XLR has clearer transient impact, more distinct images, more dimensional and separation with more air. My brother was the first to say WOW!!! Then we tried XLR 7’s with RCA 7’s from the phono to the preamp and adjusting for the difference in volume, RCA’s are 6db down in volume just like the difference in volume between RCA and XLR out from the DS. Again WOW!!! There is a bigger difference between these connection. The XLR’s are way better, just like from the dac to the preamp. I’m sorry for those that do not hear this difference, but you are really missing out on how much better your equipments can sound using XLR 's if your equipments are designed for XLR’s. My brother even bought the Decware that keeps the XLR output from the dac and outputs it to the single ended Conrad Johnson Gat preamp and is thrilled by what he heard. He says much fuller and more body and less lean sounding with the Decware. After what he heard with my phono, he will try the Decware there also since he has the same phono as me. We shall see.
BTW we did compare the WW Platinum Eclipse 8’s RCA with the 7’s RCA between preamp and power amp, and no doubt, the 8’s are more resolving and better cable.
Isn’t there a need for converting the signal back and forth from the electrical to optical circuits?
Would those converters be immune from EMI/RFI interference that may be introduced?..as well as the signal degradation introduced with the circuitry?
Like it or not, here are the facts on RCA verses XLR…I have covered this in the tech literature so I keep no secrets;
XLR - Advantages are low noise as they use a simple common mode circuit to remove that external noise…in a perfect world. Each wire in the cable is NOT “identical” to ground. This will be seen in a test called CUB, Capacitance Unbalance. This defines how much noise the cable radiates through unbalanced loop area, and how much noise it can cancel. BOTH wires to ground need to be the exactly same. They aren’t. Close, yes, but not exact. The difference causes what is called COMMON MODE TO DIFFERENTIAL MODE NOISE CONVERSION. Yes, this makes the NOISE a part of the SIGNAL and also radiates the signal in the cable out of it like a transmit antenna. Good cables aren’t afraid to tell you the CUB spec, and that should be less than 3.0% unbalance.
On XLR and shields. If an XLR is “perfect” we don’t need a shield, yes? But they aren’t so we use a shield to REDUCE the ingress ~ 80 dB with a 95% braid shield and thus the CUB has a lower voltage to deal with that gets converted to a differential signal on the two wires, and is now part of the analog signal. We can improve an XLR with a shield if we design it well such that the shield isn’t screwing up the CUB worse than 3%. A geometrically sloppy shield distance to each wire along the cable isn’t going to be nice to CUB values.
Another trick is to use lower DCR star quads. Yes, this is far more complex to make identical as we have FOUR wires…or even sixteen in my case. But, brute force signal level pushes the noise down farther. Simple signal to noise.
The 4x4 lowers the signal wire DCR to be the same between RCA and XLR. The RCA is the signal wire, and the return shield is “zero” to a simple approximation. The XLR is THERE, and then BACK but we use TWO signal wires in parallel with a star quad so they are half the resistance so the “loop” is essentially the same DCR as the RCA. This is why I don’t make a non star quad XLR. I want to MATCH the RCA’s properties as an RCA is a good cable to match! More to it than that that I can’t get into here. Read the tech papers to see how cable REALLY works.
Even if you use a true differential circuit where there is NO GROUND, just the EMF potential between the two wires, each wire is a “hot” but opposite EMF, we will still be offset with the common mode noise conversion…same as an Ethernet cable. Ten volts on BOTH wires is 10-10 =0 volts. But 10 volts on one wire and nine volts on the other leaves 1 volt of noise from CUB.
The pro’s use XLR because the noise is “generally” ~ 65 dB (not infinity) with a good XLR. The CABLE SIGNAL quality is very good but can’t be as good as an RCA cable signal, here is why;
RCA - this tech uses a SINGLE signal wire to a ground. We don’t have to worry about common to differential noise conversion. The SIGNAL on the cable is better EXCEPT if…we have to worry about inductively coupled noise through the shield between components at differing ground potentials coupling noise to our signal. And, there is ALWAYS a ground difference and at best, it is the DCR of the cable shield. No better. There is always SOME ground current moving in the RCA shield. This is why you need to use a very good ground on RCA and NEVER use a XLR wired as an RCA as they are not designed to be single end optimized. E=I*R and we can control shield R to multiply with I and that reduces E.
XLR are the noise rejection champ as common mode to differential mode noise conversion isn’t as bad as shield current noise on long enough lengths. Short reach and RCA can and are excellent signal leads. Get long enough and XLR are better designed for that with lower wire DCR (if designed right) and noise cancellation.
Be aware that the CABLE is not the “system” with an XLR. The I/O has to be more carefully considered before we make a blanket statement on one cable is better than the other, The CABLE, or the SYSTEM? I can report how the cables work.
Leaving out the XLR’s “balanced” input and output devices is not a good idea. Those I/O circuits ALSO have balance issues and influence what you hear. They are part of the deal and have to be of high quality to make the channel an advantage on noise rejection. Unbalance can come from ANYWHERE in the chain.
The answer isn’t what you really want as it isn’t JUST the cable you are evaluating. Single ended systems are simpler, and cheaper and better with low shield DCR and reasonable lengths. My MC phone uses RCA, and at over thousands of times voltage gains (66 dB). The signal is about where the noise is reduced to in an XLR! ) 0.35 mV volts (0.00035 volts) takes at least a thousand fold gain to be useful.
XLR take better care of longer runs. So use each cable properly, and for heavens sake don’t use an XLR as an RCA. The shield isn’t low enough DCR to make an RCA work well. It will “work” but the ground noise is exponential to the ground current’s induced noise as it is a magnetic property that decreases with the squared law. You want a HEAVY and low DCR with RCA as that is their weakness…as is common to differential mode noise conversion impacts the XLR.
These aren’t rumors, it is just how the cables work. Better understanding on the fundamentals, and getting them right, allow all our mysterious tertiary elements to be on a better foundation.
Best,
Galen Gareis
iconoclast design engineer
The effects of a balanced circuit on sound quality is quite considerable. When you defeat it by running single end, it is like hearing a second generation of an original recording. It doesn’t take long to hear it. Some equipment don’t even let you use single end at all, like the Boulder 1008. XLR’s only. You can use adapters but it just kills the sound as I tried. If your component have balance, you are really doing a disservice to that component by using RCA’s. I don’t think it’s just a reduction in noise I’m hearing with the extra clarity from XLR’s. Whatever it is, you hear more of what’s in the recording with XLR’s.