When Does Balanced Matter?

[dallasjustice]

Benchmark application notes explains why balanced is superior to unbalanced and under what circumstances it really matters.

https://benchmarkmedia.com/blogs/application_notes/balanced-vs-unbalanced-analog-interfaces

 

[RayDunzl]

"Copper braid and foil shields do not provide any protection against magnetic interference. Magnetic fields easily pass through copper and foil."

Having nothing to add to the discussion in the link, and having been too lazy to open a thread, and this sentence in the notes reminding me, here's an amusing video with copper and magnets showing magnetism passing through, but modified by copper...

 

[Speedskater]

Balanced interconnect systems matter when:
a] The interconnects are more than 10 feet (3 meters) long.
b] The hi-fi components are plugged into two different AC power circuits.
c] The system is in a harsh noise/interference environment.
d] When from a noise/interference one or both of the components have poorly designed input or output stages.

It's not about the cable, it's about:
the output stage >> cable >> input stage

 

[pirad]

Home users need balanced like a fish needs a bicycle.

 

[Fitzcaraldo215]

Home users need balanced like a fish needs a bicycle.

Actually, with Mch systems, including home theater, I think it is the way to go. That is particularly true if surround and back channel amps are close to the speakers with long interconnects. My balanced surround/rear interconnects are 10 meters times 4 channels under my listening room floor in 7.1. I feel that long, balanced interconnects and short speaker cables are the most desirable configuration.

Pro HT installers much prefer balanced because it provides a more reliably secure connection perfectly in just seconds without any fuss. I have only got 8 channels, but imagine the issues with today's Atmos and Auro 3D systems with 16 or 32 channels.

The other thing is just the much greater pleasure I get from using the beautifully engineered XLR connector vs. the downright awful RCA connector. I may not "need" XLR balanced, but I have eliminated all RCA connectors from my system with no regrets whatsoever.

 

[pirad]

Connector pleasures and ease of work for installers aside, I must disagree with the “short speaker, long signal cables” for home installations philosophy. Speaker cables carry significant AC currents and are way more immune to EMI than signal cables.
In a pro environment signal cables often have to be long (hence balanced), at home there is no reason for it.

 

[March Audio]

Connector pleasures and ease of work for installers aside, I must disagree with the “short speaker, long signal cables” for home installations philosophy. Speaker cables carry significant AC currents and are way more immune to EMI than signal cables.
In a pro environment signal cables often have to be long (hence balanced), at home there is no reason for it.

Sorry pirad this isn't correct. Balanced signal cable has no issue with noise immunity and avoids the potential for ground loop issues over single ended. The effect of speaker cables is quite measureable.
Whilst it isn't necessary per se, I use balanced and recommend others do too. All things being equal if will provide best signal integrity/lowest noise. I run active dsp speakers.

 

[watchnerd]

Are phono signals inherently balanced?

I've heard some say 'yes' via floating ground, others say no.

 

[RayDunzl]

Are phono signals inherently balanced?

A typical stereo cartridge has 4 pins, L and R, + and -. The signal appears "across" the +/- pins.

How is that not suitable for balanced operation?

If you ground the - (or the +) the signal appears on the other pin.

That can have the interpretation of unbalanced.

Take your pick, for whether you have a differential or single-ended input to your phono preamp.

 

[March Audio]

Are phono signals inherently balanced?

I've heard some say 'yes' via floating ground, others say no.

Well to my mind yes, certaonly in the sense that like a microphone, it could take advantage of a differential amp input and the benefits of its common mode rejection.

Being from an instrumentation background, I am somewhat bemused why you wouldn't want to use a differential phono amp.

 

[Blumlein 88]

Yeah audiophiles worry about so many ridiculous noise issues and then want to argue about balanced connection which eliminate so many real noise issues. Considering the marginal cost it's a no brainer to me.

 

[pirad]

Home users need balanced like a fish needs a bicycle.

Sorry pirad this isn't correct. Balanced signal cable has no issue with noise immunity and avoids the potential for ground loop issues over single ended. The effect of speaker cables is quite measureable.
Whilst it isn't necessary per se, I use balanced and recommend others do too. All things being equal if will provide best signal integrity/lowest noise. I run active dsp speakers.

What “effect” of speaker cables with home installation lengths?
Can you refer to some scientific peer reviewed double blind research?
Some DSP/active speakers indeed force home users to use longer signal cables.
Exotic brands like ATC (actually no DSP), Meridian apply the technology from the pro world. But there are also solutions with speaker cables, for my Linkwitz LX 521 I used 8-pole speakons. As for ground loops let’s not even get into that. One can start another thread with Bill Whitlock paper as the basis.

 

[oivavoi]

In that interview with Roger Sanders I posted some time ago, he claimed that noise and distortion levels are higher in balanced topology, so that it becomes an inferior choice unless one has significant noise to deal with.

Is he wrong on this? I have noticed, though, that some of the amplifiers that have been tested in stereofile have had higher noise and THD on the balanced inputs - but that may well be because the balanced input is just added as an extra on otherwise unbalanced topology, which means extra circuitry. Amplifiers and gear which only operate in balanced mode may not have this problem.

FWIW, I've never perceived noise to be a problem in my home environment when using unbalanced connections. Yet I still use balanced at the moment, because most of my gear is from the pro world.

 

[RayDunzl]

I have balanced power... for whatever that is worth...
Digital sources... S/PDIF/Toslink used...
XLR from DAC to preamp...
XLR to the little JBLs...
CAST or XLR from preamp to amps...
Differential (balanced) from amps to the MartinLogans...
Unbalanced to the self-powered Cheezewoofers...

The JBLs have a little hiss I can only hear with my ear very close to the speakers.

The MartinLogans are silent unless playing...

The subs are quiet...

The ceiling fan has a little 120Hz hum... And a little whoosh from low speed muffin fans that I never notice if anything is playing...

In that interview with Roger Sanders I posted some time ago, he claimed that noise and distortion levels are higher in balanced topology, so that it becomes an inferior choice unless one has significant noise to deal with.

Speaker distortion (panels or cones) still seems to be what shows up first, along with whatever ambient noise there is around.

 

[Wombat]

http://www.rane.com/note151.html

Get the best shielding: https://www.iewc.com/resources/technical-guide/popular-shielding-types

 

[March Audio]

What “effect” of speaker cables with home installation lengths?
Can you refer to some scientific peer reviewed double blind research?
Some DSP/active speakers indeed force home users to use longer signal cables.
Exotic brands like ATC (actually no DSP), Meridian apply the technology from the pro world. But there are also solutions with speaker cables, for my Linkwitz LX 521 I used 8-pole speakons. As for ground loops let’s not even get into that. One can start another thread with Bill Whitlock paper as the basis.

I have measured the filter effect.

Ground loops are a real problem. Having one of your signal conductors connected to ground where it can be modulated by circulating currents is a dumb idea, especially when it can be easily avoided. I suggest you look at some of the data Amir has collected about power supplies and their effects.

If you are looking for data to prove it is audible then you are missing the point. The point being it is a problem that can simply be avoided, however small it may be in absolute terms. Its a bit like the Schiit debacle. Some would argue the measured technical flaws are inaudible, but when you can buy an alternative technically far superior product for less then why bother with all that Schiit? So to say balanced is pointless in home installs is simply wrong.

 

[March Audio]

In that interview with Roger Sanders I posted some time ago, he claimed that noise and distortion levels are higher in balanced topology, so that it becomes an inferior choice unless one has significant noise to deal with.

Is he wrong on this? I have noticed, though, that some of the amplifiers that have been tested in stereofile have had higher noise and THD on the balanced inputs - but that may well be because the balanced input is just added as an extra on otherwise unbalanced topology, which means extra circuitry. Amplifiers and gear which only operate in balanced mode may not have this problem.

FWIW, I've never perceived noise to be a problem in my home environment when using unbalanced connections. Yet I still use balanced at the moment, because most of my gear is from the pro world.

This is another untruth Im afraid. There is just no basis to it. I think it comes from the idea that balanced circuits have more components therefore that is bad. Im playing with these at the moment, oh what terrible performance it has being differential

http://www.thatcorp.com/1510-1512_Audio_Preamplifier_ICs.shtml

http://www.thatcorp.com/1580_Low-Noise_Differential_Audio_Preamplifier_ICs.shtml

 

[oivavoi]

This is another untruth Im afraid. There is just no basis to it. I think it comes from the idea that balanced circuits have more components therefore that is bad. Im playing with this at the moment, oh what terrible performance it has being differential

http://www.thatcorp.com/1510-1512_Audio_Preamplifier_ICs.shtml

View attachment 12425

Thanks, good to know! If there's nothing to that claim, there's indeed no reason not use balanced connections.

 

[March Audio]

Thanks, good to know! If there's nothing to that claim, there's indeed no reason not use balanced connections.

As always there appears to be absurd logic in the audiophile world. Professional instrumentation will usually use balanced (differential) with small signals. Microphones use balanced (differential) as do most other professional audio applications and yet hifi insists on single ended. Why wouldnt you use balanced (differential input) with a turntable? Works very well with microphones You would think we would all complain about the terrible distortion caused by it on all the recordings we own

 

[pirad]

I have measured the filter effect.

Ground loops are a real problem. Having one of your signal conductors connected to ground where it can be modulated by said currents is a dumb idea, especially when it can be easily avoided. I suggest you look at some of the data Amir has collected about power supplies and their effects.

If you are looking for data to prove it is audible then you are missing the point. The point being it is a problem that can simply be avoided, however small it may be in absolute terms. Its a bit like the Schiit debacle. Some would argue the measured technical flaws are inaudible, but when you can buy an alternative product for less why bother with all that Schiit. So to say balanced is pointless in home installs is simply wrong.

And I have thought it is a scientific forum.