When to choice XLR over RCA ICs.

@williewonka If single-ended all bets are off. There is no way you can prevent single-ended cables from having an artifact unless you introduced a standard and had all the cables made to meet that standard, which would probably include a low impedance termination. That in turn would likely prevent most single-ended preamps made today from supporting the standard. So yes, I can imagine all the things you listed making a difference.

My point here is simply that's a bad thing- not a good thing because no matter how good your cable is now, next year, sooner or later, there will be a better example of that cable and so the cable you have now will be so much junk.

In my example of ARC, it’s listed in the specs, it can be measured and - most important - it can be heard. It is very, very real.

@cleeds To accomplish that theoretical 6dB lower noise per gain stage, the constant current source has to be excellent performance so it can force the actual differential amplifier to be as differential as possible. And as you say, it is not only measurable but also audible; we're on the same page- its very, very real.

@williewonka I'd be curious to see if there is a difference in the sound of the cables when the supporting equipment also supports the balanced standard.

Just like single-ended, if the balanced line standard isn't supported you hear big differences between balanced cables.

But the goal of the standard is to eliminate that problem- because it is a problem! Plug and play is the goal, regardless of the cable and over the last 70 years or so, its worked really well (all hifi recordings from the 50s and 60s used balanced lines).

So it would be really interesting to see if OCC wire actually made a difference.

In my view, an extra 6db gain does not result in improved dynamics, clarity and details - it’s just louder

Since personal preferemces tend to play a large role in cable selection e.g...

• I’ve known people that prefered using Duelund tinned copper over pure OCC copper, just because it sounds better to their ears
  • technically, OCC is faster and less prone to the timing distortions that occur when you mix two types of metal

But debating the differences between XLR and RCA for a high performance cable really is a moot point, however...

• people should be aware that the differences really are miniscule in high quality cables today, so opting for RCA is not really settling for second best any more

No, it's not just "louder." For the same output level, the differentially balanced connection (such as with ARC) will yield a 6 dB better s/n

Why would I forsake that 6 dB gain (or s/n advantage) in a connection such as between pickup arm and phono preamp?

@williewonka @cleeds The 6dB increase in volume only occurs if the balanced line standard is ignored.

For example in the case of a phono cartridge, the output level does not change if the cartridge is operated either way. IOW the cartridge when operated balanced, conforms to AES48 (the balanced standard).

But if operated balanced, you have up to a 6dB improvement in the signal to noise ratio of the gain stage itself. You also have the rejection of noise that is common to the non-inverted and inverted parts of the signal. So a power transformer by the cable is far less able to induce hum into it.

The 6dB improvement in signal to noise of the gain stage is theoretical. The greater the differential effect that is winnowed out of the gain stage the more you approach that possibility. To that end, and this is directed at cleeds, the constant current source feeding the differential amplifier is the key to the differential amplifier's performance. So if you wanted to improve your ARC preamp's performance this would be the thing to investigate. 

I see the really big advantage of balanced lines in that you don't have to have an expensive cable with exotic materials for it to sound just as good as a cable that does have the exotic construction and materials. IOW you get cable immunity. I've demonstrated this many times over the last 40 years.

Where this really plays out well is the tonearm cable! If there is any place to really get it right, this is it, because no matter how good your preamp, amps and speakers are, they can't make up for any losses to the signal upstream.

@ketchup Either will work fine. I use the 2449 in my system. The quad core is a bit better if you have a noisy environment as the quad construction helps with noise rejection.

Can you recommend some good bulk cable?  I'd like to make a few balanced cables to try in my system.

@ketchup Mogami Neglex is the gold standard of high quality balanced cables in the studio. They employ oxygen free copper and polyethylene dielectrics (the only thing better perforamance is Teflon, but it does not prevent oxidation of the conductor inside, so polyethylene might be the best thing out there), so in that regard are on par with cables from the high end audio world- I've seen Mogami products rebranded on that account.

@elliottbnewcombjr Yes. I got that; in my post above that is what I was talking about. I should have been more specific.

The balanced signal volume is a barely, but recognizable increase in volume, no way is is that much.

@elliottbnewcombjr Hm. That might be because the balanced output is a completely separate circuit from the single-ended output.

Turns out Pro-Ject has a line of balanced turn tables, using what looks like "microphone style" XLRs, such as this

@davetheoilguy Triplanar offers their arms with a balanced connection as well.

The value of a balanced system using balanced lines is not confined to those two goals. This is where you drift into circular reasoning. (As you well know, balanced systems also enjoy the benefit of CMNR, whether AES48 compliant or not.) Nor is it true that being non-compliant with AES48 inherently subjects a product to being sensitive to ground loops.

@cleeds Yes, we covered other aspects already. I do not see how there is circular reasoning, but I do feel I've been having to repeat myself on this a bit 😁 That's circular, isn't it?

It is true that if the component does not support AES48 that it will be open to ground loops. This isn't to say that will always happen, just as with single-ended gear it doesn't always happen. But if you don't take steps to deal with the ground loop issue, it'll be a problem sooner or later. This is fact, simply because ground is being referenced by the equipment, and when ground is referenced, then noise in the ground can get amplified. That is why in balanced systems going back 70 years ground is ignored.

I don't care to debate this either since I've repeated myself so much (not all on this thread). I have been amazed at how much misinformation exists around this topic. But if you have the interest, you might take a look at this book on transformers by Bill Whitlock, of Jensen Transformers fame.

If you look at the schematics, you'll see there are no center taps- that in fact the balanced inputs and balanced outputs are always floating.

You do not inherently lose "most of the benefit" of balanced components by not supporting AES48, imo. Sometimes it’s better, sometimes it’s not.

@cleeds The two benefits lost are cable immunity and susceptibility to ground loops, since ground is referenced by the output of the device. This isn’t a matter of opinion or debate. Those two things are literally the goals of the balanced line system. The cable immunity aspect is what made long distance phone calls possible- so it was the phone company that embraced balanced lines first. Record labels saw very quickly what that benefit was for placing mics properly and being able to run long cables without noise or bandwidth problems. This was one of the most important technologies to usher in the age of HiFi in the early 50s.

But imagine a room full of equipment, and I mean full. You literally can’t afford to have a ground loop shut you down, it might take days to find the errant component while an orchestra is on the clock.

I’ve seen and heard AES48 compliant balanced components that sounded w-a-y better on the SE inputs and you probably have, too. When cheap tiny xformers are used for the conversion it can suck the HF right out of the sound. Same thing if cheap opamp ICs are used.

Yeah, once you’ve heard it done right there’s no going back.

Most of the equipment I’ve seen that supports AES48 is studio gear. I’ve yet to see a cheap line transformer in it, but that’s different from sucking the life out of the sound. Some of that gear I have are compressors and I only use them in emergency, since sucking the life out of the sound is basically what they do. But they have nice transformers....

Generally you can’t use opamps to support AES48. This is due to the fact that the output has to be floating and not referenced to ground. Opamps have single-ended (but likely push pull, so single-ended as opposed to balanced...) outputs. Those output circuits don’t take kindly to another opamp sinking current in them- they will blow up. So instead you need a line driver IC like this. Otherwise you might have an opamp driving some transistors which in turn drive an output transformer.

Most implementations of AES48 compliant outputs are going to be pretty decent simply because its aimed at the recording studio. But that says nothing about how the equipment sounds- that’s a whole ’nuther issue!

I’m mostly harping about the plug and play issue, which is wrapped around the fact that the cables can always be inexpensive; no need for audition.

What is the greatest advantage of using balanced components? There are multiple advantages, so the answer is subjective and debatable. In my view, the answer is lower noise. That would explain why we see so many differntially balanced components that do not comply with the AES48 standard that you tout.

There are several ways of designing an AES48 compliant component, and some have negative sonic effects. So the AES48 standard is not itself a guarantee of performance.

Of course! But it is a guarantee of plug and play insofar as the cables are concerned.

I don't know of a way that has a 'negative sonic effect' that is specific to AES48. Perhaps you could point one out to me.

I know of a good number of reasons that can cause a 'negative sonic effect' when the standard isn't supported, for example a ground loop. Nasty, and easily detected, so not really subjective.

The advantages of balanced components is different from balanced cables, since you can have single-ended equipment that uses balanced connections, like my RCA and Westerex microphone preamps.

But if we stick to your question above, the advantages are several. Its more than just lower noise; item 6 would seem to be the one in which most audiophiles would be interested, although IME that isn't always the case:

1) lower noise in each gain stage (if the circuit is differential; a 6dB theoretical noise reduction per stage of gain), You can see an advantage for high gain circuits like a phono section where you might have 12 or 18 dB less noise than an equivalent single-ended circuit.

2) greater power supply noise immunity

3) Greater rejection of magnetic fields (like from a power transformer) that might be close to the equipment

4) rejection of noise imposed on the interconnect cable by a power cord, transformer or the like (Common Mode Rejection Ratio is the term used for this)

5) immunity to ground loops

6) (if AES48 is supported) interconnect cable immunity; IOW no sonic effects caused by the cable itself.

Only item 6 might be considered subjective although its easily demonstrated so its the only item of debate.

The advantage of the cable itself is it does not have to be expensive to work perfectly. This is also easily proven so really isn't debatable.

What is debatable is the use of balanced lines actually being an advantage when the standard isn't supported. That is why this thread exists. Sometimes its better, sometimes its not, because in this circumstance, the benefit of balanced lines isn't fully realized.

2. Slight Volume Increase. No ’better’ or ’preferred’ or ’different' sound, but a discernable volume increase, IF that makes a difference. btw, other equipment, no volume difference, so it’s the Sony xa5400’s output that is slightly stronger, not the cable.

@elliottbnewcombjr If this is the case, it means the Sony doesn't support the balanced standard. Instead, what it has is two single-ended outputs, one out of phase with the other. So when you run balanced you get 6dB more output.

If it supported the balanced standard, the output level would not change.

When this sort of thing goes on, you lose most of the benefit of going balanced. You retain the noise aspect, but the choice of cable will become important to get the best sound and you might have to deal with a ground loop (since ground is being referenced by the output of the player). Neither is an issue if AES48 is supported.

^ +1

There is no real difference at one meter. 

This statement is incorrect. Balanced operation can be beneficial even if the connection is only 6", since rejection of noise impinged in the cable is not a function of length. If operating balanced, that noise is rejected at the receiving end.

Max Townshend told me that RCA's are the way to go over XLR's because RCA's give "pure sound". That the additional circuitry in XLR's detract from the pure sound..

@vinylshadow 

This is a common myth. If it were so, then recordings would all use single-ended connections, which they don't. The Golden Age of Stereo, which began in 1958 with the introduction of the first stereo LPs, was also ushered in by balanced lines, which allowed microphones to be placed correctly without the recording equipment being only a few feet from the performers. So this meant you could record in concert halls and the like without signal degradation before it hit the mic preamps in the tape machines of the time.

What is important to understand is the signal in a balanced line connection isn't push pull any more than it is in a single-ended cable- as long as the setup is compliant with AES48, the balanced line standard. You'll note there really isn't a standard for single-ended cables...

Literally everything in my system except the turntable have balanced connections, and I’d do that, too if I could find a turntable Inlike that was balanced.

@davetheoilguy 

Usually all that is required is to change out the tonearm cable. Sometimes, on cheaper stuff, this might require some soldering. But on tonearms that have the 5-pin DIN connection or RCAs with a ground post, its a simple matter of changing the cable so you can run balanced. In the case of the RCA connections, the shield of the cable goes to the ground post and the two RCA connections (center pin and the barrel) are the twisted pair within the shield. At the XLR input of the preamp, the twisted pair are pins 2 and 3 of the XLRs and the shield is pin 1. On no account should the shield of the cable contact the barrel connection of the RCA. This works a treat- you can use Mogami console wire which is low capacitance and this will work as well as any single-ended cable regardless of cost.

I've always seen the need to audition expensive cables as a hidden cost of single-ended preamps. When you run balanced, the cable cost is inconsequential if the equipment (such as the phono cartridge) supports AES48.