Balanced (XLR) vs. Regular RCA Interconnects

[toucanet]

I was reading the opinions of posters on this subject from 2003 to 2007 (http://www.polkaudio.com/forums/arch...hp/t-8628.html).

As of July 25, 2010, what are your opinions of the Balanced (XLR) vs. Regular RCA interconnects?

Does is one better than the other for tube gear?

Which do you currently use and why?

Which make/model would you purchase today?


Thanks in advance.

[SivaNevets]

i do both home stereo listening and some studio recording, the real world difference it, when u using unbalanced interconnections and u have other devices like a mouse, ull hear some interferrence by clicking the mosue button from speakers.
and the other disadvantage is if the cable is longer than 20m, RCA will have problem.
other than that i dont think they make any difference.

[danz1906]

Hello,

I use Harmonic technology Pro-Silkway III balanced cables.

[Face]

If your gear is fully balanced, you'd be silly to not used balanced cables.

[Ricardo]

Look at the bottom of this thread under "Similar Threads". Also do some search. It's been discussed many times.

[toucanet]

Look at the bottom of this thread under "Similar Threads". Also do some search. It's been discussed many times.

Thanks for the advice Ricardo. However, research was done; there's a referenced thread in my original post.

I am curious since the technology has changed from 2007 to 2010 and am interested in present technology.

[heiney9]

This has been discussed numerous times since 2007, search again. No, technology hasn't changed in 3 years. Everything still applies in those threads as well as the dozen or so from 2007-2010.

It's more about how the gear is designed for balanced operation than it is about the cables. All the standard and well debated cable caveats remain whether it's single ended or balanced.

H9

P.s. Perhaps the OP could be more specific about how they are being used because that has the largest impact in the difference between the two.

[heiney9]

I've used Signal Cable and MIT and if I were currently using the balanced inputs I would still use either of those today leaning heavily towards the MIT.

In my system (as I've posted in several other theads on this subject) I prefer the single ended RCA connection over balanced. It's a personal preference based on how they sound. I have compared the exact same balanced and single ended cable and the single ended cable sounds better to me in my system, in my room.

But then you should already know my POV (beacuse you have done the search) as this is about 15th time I've posted it here on CP in these exact types of discussions.

H9

[toucanet]

This has been discussed numerous times since 2007, search again. No, technology hasn't changed in 3 years. Everything still applies in those threads as well as the dozen or so from 2007-2010.

It's more about how the gear is designed for balanced operation than it is about the cables. All the standard and well debated cable caveats remain whether it's single ended or balanced.

H9

Thanks heiney9 and others,

Once again, you, Ricardo and numerous others continue to be a wealth of knowledge to the novices, such as myself.

Since my recently acquired gear has the XLR hardware, I will give the XLR cables a try.

I will be using them to connect a Rogue Hera II preamplifier to a pair of Rogue Apollo monoblocks. My speakers are 1.2TLs, my CD player is a Jolida JD100 (RCA ICs).

[Kenneth Swauger]

Hello,
H9 is correct, the associated audio gear has to be designed correctly for a balanced topology to be fully realized. This means the complete signal path, gain stages, volume controls and output stages have to be balanced. I believe the 80s/90s era Mark Levinson components are "really" balanced designs, from input to output.
Maybe the Boulder products as well.
Enjoy, Ken

[heiney9]

Thanks heiney9 and others,

Once again, you, Ricardo and numerous others continue to be a wealth of knowledge to the novices, such as myself.

Since my recently acquired gear has the XLR hardware, I will give the XLR cables a try.

I will be using them to connect a Rogue Hera II preamplifier to a pair of Rogue Apollo monoblocks. My speakers are 1.2TLs, my CD player is a Jolida JD100 (RCA ICs).

Nice rig! I would give both a try and see which you prefer. My preference for RCA over Balanced was slight and when I upgrade to another Pass Labs amp (X series) I will use the balanced connections because those amps were designed especially to be used in a fully balanced system for the best performance.

H9

[Face]

Since my gear is fully balanced I thought I'd try out a pair of balanced cables. Using the same cables(Neotech NEI-3004) I swapped my Eichmann bullet RCA connectors out for a pair of Vampire XLR connectors. What I experienced most notably was a larger soundstage and more powerful bottom end. Needless to say, I was pleased with the results.

[TNRabbit]

Stolen from "Audio Power amplifier design handbook" by Douglas Self:

Balanced Interconnections
Balanced inputs on power amplifiers are used to prevent noise and crosstalk from affecting the input signal, especially in applications where long interconnections are used. They are standard on professional amplification equipment, and are steadily becoming more common in the world of hi-fi. A balanced input amplifier is sometimes called a line receiver. The basic principle of interconnection is to get the signal you want by subtraction, using a three-wire connection. In some cases a balanced input is driven by a balanced output, with two anti-phase output signals, one signal wire (the hot or in-phase) sensing the in-phase output of the sending unit, while the other senses the anti-phase output.

In other cases, when a balanced input is driven by an unbalanced output, as shown in Figure 20.3, one signal wire (the hot or in-phase) senses the single output of the sending unit, while the other the cold or phase-inverted) senses the unit's output-socket ground, and once again the difference between them gives the wanted signal. In either of these two cases, any noise voltages that appear identically on both lines (i.e. common-mode signals) are in theory completely canceled by the subtraction. In real life the subtraction falls short of perfection, as the gains via the hot and cold inputs will not be precisely the same, and the degree of discrimination actually achieved is called the common-mode rejection ratio (CMRR), of which more later.

It is tedious to keep referring to non-inverting and inverting inputs, and so these are usually abbreviated to 'hot' and 'cold' respectively, though this does not necessarily mean that the hot terminal carries more signal voltage than the cold one. For a true balanced connection, the voltages will be equal. The 'hot' and 'cold' terminals are also often referred to as In+ and In—, and this latter convention has been followed in the diagrams here.

The subject of balanced interconnections is a large and subtle one, and a big fat book could be written on this topic alone. A classic paper on the subject is by Muncy. To keep it to a reasonable length, this section has to concentrate on the areas most relevant to power amplifier interconnection.

Advantages


* Balanced interconnections discriminate against noise and crosstalk, whether they result from ground currents, or electrostatic or magnetic coupling to signal conductors.
* Balanced connections make ground loops much less intrusive, and usually inaudible, so people are less tempted to start 'lifting grounds' to break the loop. This tactic is only acceptable if the equipment has a dedicated ground-lift switch that leaves the external metalwork firmly connected to mains safety earth. in the absence of this facility, the optimistic will remove the mains earth (not quite so easy now that molded mains plugs are standard) and this practice is of course dangerous, as a short-circuit from mains to the equipment chassis will result in live metalwork. A balanced interconnection incorporating a true balanced output gives 6 dB more signal level on the line, which should give 6 dB more dynamic range. However, this is true only with respect to external noise — as the section below describes, the electronics of a standard balanced input is more than 6dB noisier than the electronics of an unbalanced input.
* Balanced connections are usually made with XLR connectors. These are a professional three-pin format, and are a much superior connector to the phono (RCA) type normally used for unbalanced connections (more on this below).

Disadvantages

* Balanced inputs are inherently noisier than unbalanced inputs by a large margin, in terms of the noise generated by the input circuitry itself rather than external noise. This may appear paradoxical but it is all too true, and the reasons will be fully explained in this chapter.
* More hardware means more cost. Small-signal electronics is relatively cheap; unless you are using a sophisticated low-noise input stage (of which more later), most of the extra cost is likely to be in the balanced input connectors.
* Balanced connections may not provide much protection against RF intrusion — both legs of the balanced input would have to demodulate the RF in equal measure for common-mode cancelation to occur. This is not very likely, and it is important to provide the usual input RF filtering to avoid EMC difficulties.
* There are more possibilities for error when wiring up. For example, it is easy to introduce an unwanted phase inversion by confusing hot and cold in a connector, and this can go undiscovered for some time. The same mistake on an unbalanced system interrupts the audio completely.

[Kenneth Swauger]

Many manufacturers take the incoming balanced signal, use a transformer to convert it to a single ended signal. Then do whatever signal processing happens, feed it back into a transformer and send it out as a balanced signal. This is what happens on professional tape recorders, mixers, etc. The ReVox PR99 does this and without doubt using the single ended output is much better sounding.
Naturally I can't speak for all companies, but I would venture to say that few are using a balanced circuit throughout. One look at the Levinson schematic tells you why. Everything is twice as complex, requiring a positive signal path and a negative signal path. And those components used in each path have to be matched to extremely high standards.
Kind of like true "four wheel" drive would put a motor on each wheel instead of one motor for four wheels.
Regards, Ken

[falconcry72]

Hello,
H9 is correct, the associated audio gear has to be designed correctly for a balanced topology to be fully realized. This means the complete signal path, gain stages, volume controls and output stages have to be balanced. I believe the 80s/90s era Mark Levinson components are "really" balanced designs, from input to output.
Maybe the Boulder products as well.
Enjoy, Ken

I have a Parasound p/ld-2000 preamp and a HCA-2200mk2 poweramp (real John Curl stuff). The pre has balanced outs and the amp has balanced ins, but is this gear "really" balanced throughout? My current CDP does not have balanced outs, but that's a feature I would look for in an upgrade if the amp and preamp are worth doing it with.

[Kenneth Swauger]

Hello,
I bet if you could corner a well respected audio designer and get him/her with one or two drinks under their belt and ask about balanced circuits you'd probably hear, "Yea, we have to put balanced connections on the stuff. It's this year's "buzz word" and you gotta have it. To do it the right way would be too expensive, nobody would buy it. We stick some XLRs on the back and everybody's happy!"
In recording studios and on location recording the enemy is humming and noise. Microphone cables run for hundreds of feet and pass beside high power lights and other sources of EMI. So every component is connected with balanced cables, it reduces the chance of getting hum. You probably won't find a single ended cable anywhere. They have polarity switches on all power connections and "hum buckers" on electrified instruments and amps. Literally humming costs money, lots of money. That's where balanced connections are necessary. But the actual gear itself is single ended and uses matching input/output circuits.
Cheers, Ken

[heiney9]

Here is a great article from a well respected designer.

http://www.passlabs.com/pdfs/articles/susy.pdf

http://www.passlabs.com/pdfs/articles/xa_paper.pdf

Understand the concepts and don't let the tech-speak scare you away. Nelson has a way of taking technical ideas and making them understandable to us mortals.

The first article explains why the "X" series amps actually perform better using the balanced inputs and explains typical balanced operation better than anything I've read on the subject. The amps were designed that way from step one.

[Kenneth Swauger]

Hello,
Thanks for the references. He makes my point by describing the three popular methods of designing balanced circuits (for those companies that actually have a balanced design) and indicating that they do nothing to reduce distortion. In fact, they sound worse. His approach is not to reduce noise or distortion, but to reduce the unwanted effects of negative feedback by tweaking each "half" of his balanced circuit topology to reduce the need for as much negative feedback.
He's saying that even if the design uses true balanced design the need for high amounts of negative feedback required produces a poorer sound quality. So, unless the designer knows what he's doing (certainly applicable with Nelson Pass) it is better to keep the circuit simple and use a single ended approach.
Cheers, Ken

[Kenneth Swauger]

Wow, a civil discussion of a potentially controversial audio topic! The moral of the story is don't include or exclude any technology purely on the technology itself. Rather try and learn about how the manufacturer has accomplished the overall design and decide how it sounds to you and blends with the rest of your system.

[heiney9]

Yes sir, that's why I love the sound of Pass products. K.I.S.S. There is a naturalness and truthfulness to all of the Pass products even though stuff like his First Watt designs are for different audio applications. His philosophy and approach is the same across the board regardless of the intended application.

I think you summed it up very well Ken and I specifically posted that article for the first few paragraphs and it's simple, straight forward explanation of different balanced circuit approaches for the OP.

H9

[reeltrouble1]

balanced trumps unbalanced. without rehashing the echoes of so many now and so many past posts, check out your gear to see if it is balanced circuit, as the marketing guru's are now charging more for balanced cables, cuz their "better", well yea, if the gear is really balanced, balanced circuits have been used by those who cared about signal path handling, long before balanced connects came to pass, my SACD with the fully balanced circuit makes the whole rig quieter as everything is balanced, the SACD with a single ended connection though is marvelous, because the circuit is so well thought out (of course many other things), or just get 200 watts a channel and be done.

I would suggest if you have not done so to read the white papers of Victor Khomenko at Balanced Audio Technology or give him a call, or e-mail, he loves to talk about balanced circuits, balanced power, of particular interest is his view of the importance of signal width, he likes Vodka as well.

Remember there are no gimmicks in audio, so you have to do the research, so many marketing techniques (well they used to be called lies but now their techniques) spin audio truths with something else with marketing.

RT1

[cstmar01]

Hello,
I bet if you could corner a well respected audio designer and get him/her with one or two drinks under their belt and ask about balanced circuits you'd probably hear, "Yea, we have to put balanced connections on the stuff. It's this year's "buzz word" and you gotta have it. To do it the right way would be too expensive, nobody would buy it. We stick some XLRs on the back and everybody's happy!"
In recording studios and on location recording the enemy is humming and noise. Microphone cables run for hundreds of feet and pass beside high power lights and other sources of EMI. So every component is connected with balanced cables, it reduces the chance of getting hum. You probably won't find a single ended cable anywhere. They have polarity switches on all power connections and "hum buckers" on electrified instruments and amps. Literally humming costs money, lots of money. That's where balanced connections are necessary. But the actual gear itself is single ended and uses matching input/output circuits.
Cheers, Ken

awesome advice and comments Ken.

Many amps and componets do not use true balanced designs which if you are new to the hobby its hard to understand. I always find it interesting when you have an amp that says its balanced but it really is not and it can get very frustrating as a new person to understand what is truely balanced and what is not. Thanks!

[Kenneth Swauger]

No problem, glad to be of help. Actually anybody who play records already has a balanced component. Phono cartridges are balanced (except the older Decca cartridges). That's how you can reverse channel polarity on a cartridge by swapping wires and you need a separate ground connection.
Enjoy, Ken

[billbillw]

balanced trumps unbalanced.
RT1

This may be true for the designs that are truly balanced throughout, but most mainstream stuff is not. The balanced inputs/outputs are extra circuits for the signal to pass through, and often they use op-amps in the circuit to achieve the results.

In those cases, you will typically have better sound quality by using the single ended connections. Of course, this is based upon using normal cable lengths (3m or less).

I've compared the results on several of the pieces that I've owned and found in every case that the single ended sounded better.
That would be:
Parasound PLD2000-HCA2200ii combo (also tested with the Sony E80ES preamp)
B&K Pro10MC-ST1400 combo
Sony TAE90ES-N90ES combo.

[reeltrouble1]

Thanks Bill for confirming what I said.....balanced trumps unbalanced.

RT1

[heiney9]

Even though my Pass Aleph 30 is truly balanced I still prefer the single ended connection. It's not about which is "better" as a general opinion, but which I prefer based on how my rig is set-up and the current synergy. Someone could come in and listen to both and prefer balanced.

That is why I will never say Balanced is the only way to go, unless the design is specifically optimized by using the balanced connections as in BAT products or the Pass "X" series. The former and especially the later the designer states you will loose performance by running single ended. Those are special cases relegated to very high end electronics in most cases.

[reeltrouble1]

Additionally Nelson Pass has cured any hint of your developing ED.

RT1.......Balanced trumps Unbalanced......remember, I never lie, cheat, or steal, unnecessarily.

[falconcry72]

I've compared the results on several of the pieces that I've owned and found in every case that the single ended sounded better.
That would be:
Parasound PLD2000-HCA2200ii combo (also tested with the Sony E80ES preamp)
B&K Pro10MC-ST1400 combo
Sony TAE90ES-N90ES combo.

Good to get feedback from someone who's tried it with my same pre/power combo.

I'm currently running single-ended from my CDP to my PLD and balanced from my PLD to my HCA. I'm only doing that because the combo came with a nice XLR cable. I have a pair Ben's silver IC's on the way, so I'll throw'em in there and see how they compare to my ears.

[falconcry72]

remember, I never lie, cheat, or steal, unnecessarily.

but what about unintentionally? ;):p

[TECHNOKID]

I always found balanced signals to be fruitfull with most proffesional equipment and to be negligible with home audio as most home audio gear are not truly balanced. Balanced circuitry is complex and expensive, the fact that you see and XLR connector at the input doesn't warrant actual balanced circuitry. However, I will admit that there is a few high end gear out there that could well eb truly balanced.

BTW, who can decifer the above title ;) ?

NOTE: Frenchies NOT allowed to respond, NO cheating please :)