General Asylum

General audio topics that don't fit into specific categories.

Return to General Asylum

Message Sort: Post Order or Asylum Reverse Threaded

Balance vs rca inputs

71.244.154.62
Posted on April 17, 2021 at 09:10:31
tz7
Audiophile

Posts: 260
Joined: September 26, 2004
 I am trying to determine whether balanced inputs would provide an improvement in my system.

my understanding is that balanced inputs provide an improvement for long cable runs (10+ ft)

Should I expect that balanced inputs would provide any improvement if I don't have long cable runs?

What type of improvements do balanced inputs typically provide?

 

Hide full thread outline!
    ...
RE: Balance vs rca inputs, posted on April 17, 2021 at 09:42:12
Mike K
Audiophile

Posts: 13973
Location: 97701
Joined: September 23, 1999
 One big benefit is increased noise rejection. I use balanced connections
whenever possible, and typically will not buy components that don't have
them. Some manufacturers (BAT, for instance) use balanced connections
exclusively. Let your ears be the judge - you may not hear a difference.

Lack of skill dictates economy of style. - Joey Ramone

 

RE: Balance vs rca inputs, posted on April 17, 2021 at 10:46:05
tz7
Audiophile

Posts: 260
Joined: September 26, 2004
 Would it make a difference with inter connectors between amp, preamp, dac which are less than 3 feet long?

 

RE: Balance vs rca inputs, posted on April 17, 2021 at 11:01:42
SgreenP@MSN.com
Audiophile

Posts: 3537
Joined: April 23, 2007
 Unless your components are differentially balanced, it makes little difference

 

A few years ago, I had a slight hum problem with one of my inputs, posted on April 17, 2021 at 12:23:34
Chris from Lafayette
Audiophile

Posts: 26434
Location: SF Bay Area
Joined: February 17, 2004
Contributor
  Since: February 6, 2012
 I then switched its 1.5 meter cables from RCA's to (balanced) XLR's. Problem solved, 100%. At that point, I was so impressed that I switched all my connections to XLR's where possible. OTOH, if you don't have a problem now, you may not notice an improvement when switching.

 

RE: Balance vs rca inputs, posted on April 17, 2021 at 14:03:21
Todd Krieger
Audiophile

Posts: 37333
Location: SW United States
Joined: November 2, 2000
 Too many components that have "balanced" jacks, but the circuitry is otherwise single-ended......

The problem with balanced is that if you also like tubes, balanced requires double the tubes (plates) that you'd see in a single-ended circuit, and ideally, should be matched.

 

RE: Balance vs rca inputs, posted on April 17, 2021 at 15:56:15
PAR
Audiophile

Posts: 1732
Location: South London, UK
Joined: June 4, 2019
 The improvement that balanced connection makes , ceteris paribus, is that there is better rejection of parasitic noise e.g. EMI, RFI. This may or may not be a benefit depending upon your particular circumstances.

Moving from a theoretic view to practical experience, the ultimate effect upon sound quality depends upon the success of the implementation of the balanced circuitry at both ends by the circuit designer(s) concerned. This can be unpredictable in practice. So if it is better or worse in reality will mainly be a suck it and see situation. I even have a preamp where the balanced input is inferior sounding to the balanced output ( when compared to the single ended connections)!

"We need less, but better" - Dieter Rams

 

Quite unlikely. (NT), posted on April 17, 2021 at 16:27:56
Kal Rubinson
Reviewer

Posts: 12435
Location: New York
Joined: June 5, 2002

 

RE: Balance vs rca inputs, posted on April 18, 2021 at 04:05:15
Story
Audiophile

Posts: 10427
Location: NJ
Joined: December 11, 2000
 I'm in total agreement with Par. If you are not in a environment that is loaded with EMI etc you don't need balanced connections.

For instance, I'm in a basement and run 20 foot long cables from preamp to amp. I have all AC cables plugged into one power outlet thru an AC regulator with a voltage in/out readout. The listening room has a 20amp circuit installed for audio only. I don't have a lick of any anomalies whatsoever so it really depends on your environment.

Balanced connections were originally designed for long cable runs many years ago, and recording studios&live sound still use them to this day where there is no control on the environment.

I will add that equipment/system ground issues should not be confused with environmental ones.



 

RE: Balance vs rca inputs, posted on April 18, 2021 at 06:32:36
AbeCollins
Audiophile

Posts: 46280
Location: USA
Joined: June 22, 2001
Contributor
  Since: February 2, 2002
 Balanced connections can be beneficial even with relatively short cable runs in certain situations. It's not JUST about mitigating airborne EMI/RFI noise.

For example, balanced connections can eliminate audible hum from ground loops that might exist in your setup. These are not airborne EMI/RFI but ground potential differences between interconnected equipment. This is common (but not exclusive to) AV setups where Cable or Satellite TV equipment is part of the audio system.

I have personal experience with this in our previous home where the CableTV ground was at a different potential than the AC mains ground and all of my audio gear. Two ways to solve the problem: Isolate the CableTV coax through transformer or capacitor coupling. You can buy devices that do this. Use balanced interconnects to null out the hum. Or both.



 

RE: Balance vs rca inputs, posted on April 19, 2021 at 02:57:07
Story
Audiophile

Posts: 10427
Location: NJ
Joined: December 11, 2000
 the poster above me is using an example for a problem that should be addressed at the source of the problem and not a band aid like the extra expense of balanced cables, equipment, and the associated costs...unless anyone also has home theatre.

I should also say that I am not a fan of home theatre and keep forgetting it is now integratingly called 'high end' or whatever, as I do not partake. When AA was first started it was for Audio and have seen very little interest here with HT over the years.

Maybe Rod should start a specific Home Theatre forum.





 

RE: Balance vs rca inputs, posted on April 19, 2021 at 07:30:18
marlin
Audiophile

Posts: 154
Location: Sandy, Oregon
Joined: November 20, 2012
 I switched to XLR from my blue ray player to my DSpeaker preamp.The only difference I noticed was a bump in output. I had to trim the output from the player to the pre or it would max out the input.


Without music what is there?

 

RE: Balance vs rca inputs, posted on April 19, 2021 at 10:02:21
Aaron 01
Audiophile

Posts: 741
Location: Golden Colorado
Joined: July 18, 2004
 For me even matching the levels between XLR and RCA between my DAC and integrated amp, I notice an improvement in clarity and background blackness using XLR. Could be a better output stage on my DAC on the XLR, I don't know, but I do know XLR sounds better to me on a 1 metre run.

Aaron

 

RE: That can be sidestepped with an input transformer. , posted on April 19, 2021 at 13:46:58
Ralph
Manufacturer

Posts: 4769
Location: Minnesota
Joined: April 24, 2002
 Transformers allow for excellent CMRR. And you can get great bandwidth at line levels. Many recordings have them in the recording train.

 

RE: Balance vs rca inputs, posted on April 19, 2021 at 13:51:30
Ralph
Manufacturer

Posts: 4769
Location: Minnesota
Joined: April 24, 2002
 Balanced connections were originally designed for long cable runs many years ago, and recording studios&live sound still use them to this day where there is no control on the environment.

I will add that equipment/system ground issues should not be confused with environmental ones.

There are several benefits that are interleaved. In a balanced system ground is ignored so even if there are ground loops they don't get amplified.

Ground loops don't always manifest as a hum or buzz. They might show up as addition IMD when a signal is present.

Not sure what you mean by 'environment' but many studios employ power conditioning, which really has nothing to do with how effective the use a balanced lines will be.

 

RE: There is benefit even if the cable is 6 inches., posted on April 19, 2021 at 13:55:50
Ralph
Manufacturer

Posts: 4769
Location: Minnesota
Joined: April 24, 2002
 Ground is ignored so ground loops are kept to a minimum. This means less IMD in the final output too.

Magnetic fields that impinge a cable are less likely to be amplified because of the resulting signal being common to both conductors and so is rejected by the receiver of the signal.

Since there is no signal return current in the shield the construction of the cable is less critical.

One place a balanced line works really well is between a cartridge (which is a balanced source) and a phono preamp. If there is any place in a system where the cable has to get it right, this is it. You can't fix any signal downstream from flaws caused upstream!

 

RE: "A few years ago, I had a slight hum problem with one of my inputs, posted on April 19, 2021 at 14:31:45
Todd Krieger
Audiophile

Posts: 37333
Location: SW United States
Joined: November 2, 2000
 ....I then switched its 1.5 meter cables from RCA's to (balanced) XLR's. Problem solved, 100%. At that point, I was so impressed that I switched all my connections to XLR's where possible. OTOH, if you don't have a problem now, you may not notice an improvement when switching."

I guess the gear you were using had both RCA and XLR connections..... This would not work if your components were single-ended (only RCA jacks), and you tried to connect between them with an XLR cable (using adapters).

 

Question ....., posted on April 19, 2021 at 14:42:44
Cut-Throat
Audiophile

Posts: 18285
Location: Minneapolis - St.Paul Area
Joined: September 2, 2000
Contributor
  Since: May 16, 2021
 When you say that 'Ground is ignored' on a balanced system, what exactly do you mean by that?



 

RE: Ground is ignored in a balanced system., posted on April 19, 2021 at 14:56:58
Ralph
Manufacturer

Posts: 4769
Location: Minnesota
Joined: April 24, 2002
 The ground (shield) is only used for shielding. It is not used as any part of the audio signal as you see in an RCA connection.

So that means that the signal of pin 2 (non-inverting) of the XLR is created with respect to pin 3 (inverting), not ground! Equipment that does not do this is not supporting the balanced line standard and you don't get all the benefit either.

An easy way to think about this is a simple output transformer that has a single winding as its secondary with no center tap. Pin2 of the XLR is one side of the winding and pin3 is the other side. Pin1 is the chassis and might only be connected to the mounting system of the transformer.

 

RE: Ground is ignored in a balanced system., posted on April 19, 2021 at 15:47:56
Cut-Throat
Audiophile

Posts: 18285
Location: Minneapolis - St.Paul Area
Joined: September 2, 2000
Contributor
  Since: May 16, 2021
 When I build RCA Cables. I use a 2 wire cable for + and - connection. I keep the shield floating. (I have tried tying it to the - cable as well) -- Still I have problems with ground loops. My solution was to lift the grounds, and install a GFCI on the circuit for safety. I've got to say that I do have a very quiet backround doing this, and is safer with a circuit with ground plug and no GFCI.

What is your recommended solution for using gear that does not have balanced connections? Also, will balanced connections ALWAYS solve Ground Loops?

I've found very few people that understand what a ground loop is and how to solve one. They're full of suggestions that don't work however.




 

The music signal is transfered between.., posted on April 19, 2021 at 16:47:53
Tre'
Industry Professional

Posts: 17294
Location: So. Cal.
Joined: February 9, 2002



the source and the destination without any part of the signal being grounded.

Here's one example. My phono cartridge connects to the primary winding of my step up transformer with "ground" being used for nothing more than shielding. Only one channel is shown.

A normal XLR microphone connection to a mixing console is another good example.

Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"

 

RE: Ground is ignored in a balanced system., posted on April 19, 2021 at 16:54:48
Tre'
Industry Professional

Posts: 17294
Location: So. Cal.
Joined: February 9, 2002
 "will balanced connections ALWAYS solve Ground Loops?"

If you only connect the shield at one end, then yes. (as far as I know)

Tre'
Have Fun and Enjoy the Music
"Still Working the Problem"

 

Yes - both ends had RCA's and XLR's - no adapters necessary [nt], posted on April 20, 2021 at 01:32:32
Chris from Lafayette
Audiophile

Posts: 26434
Location: SF Bay Area
Joined: February 17, 2004
Contributor
  Since: February 6, 2012

 

RE: No, its if the balanced circuit supports AES48 nt, posted on April 20, 2021 at 09:50:04
Ralph
Manufacturer

Posts: 4769
Location: Minnesota
Joined: April 24, 2002
 -

 

RE: With single-ended stuff, posted on April 20, 2021 at 10:01:18
Ralph
Manufacturer

Posts: 4769
Location: Minnesota
Joined: April 24, 2002
 Chassis and audio grounds must not be the same thing in a single-ended system.

You have to ground the chassis thru the power cord for safety reasons- that is where ground loops really start to show up.

If there is some isolation between the chassis and audio ground of the amp or preamp, then you won't get ground loops. A resistor might be all that's needed to sort this out. Older equipment of course solved this by not grounding the equipment at all.

Balanced connections in high end audio will not always be ground-loop free although they *should*. If AES48 is observed in the equipment there will be no ground loop problems even though all the chassis involved are grounded.

If you had to lift grounds to get rid of ground loops there is a design flaw with the grounding scheme of at least some of your equipment. BTW A GFCI won't give you much protection if the grounds have been lifted!

You should be able to just plug and play. But so much of high end audio is done by folks who don't have a full grasp of how stuff like this works. Grounding in particular is poorly understood.

 

RE: With single-ended stuff, posted on April 20, 2021 at 10:15:03
Cut-Throat
Audiophile

Posts: 18285
Location: Minneapolis - St.Paul Area
Joined: September 2, 2000
Contributor
  Since: May 16, 2021
 You don't even need a Ground wire, much less a 3 Prong Plug for a GFCI to work. That's what a GFCI is for: this is per the NEC.

"A grounding-type receptacle that is GFCI protected without an equipment grounding conductor is a safer installation than a grounding-type receptacle with an equipment grounding conductor (if GFCI protection is not provided). This is because the GFCI protection device will clear a ground-fault when the fault-current is 5 milliamperes (+ or - 1 milliampere), which is less than the current level necessary to cause serious electric shock or electrocution."

"One of the methods permitted in 406.4(D)(2) is to replace a non-grounding type receptacle with a GFCI type receptacle. When doing this, the 2014 NEC required the "receptacle" to be marked "no equipment ground".

https://www.electricallicenserenewal.com/Electrical-Continuing-Education-Courses/NEC-Content.php?sectionID=306.0




 

RE: That's a new one on me!, posted on April 20, 2021 at 10:53:20
Ralph
Manufacturer

Posts: 4769
Location: Minnesota
Joined: April 24, 2002
 I had always assumed that a GFCI needed a ground to detect a fault.

 

RE: That's a new one on me!, posted on April 20, 2021 at 13:42:36
Cut-Throat
Audiophile

Posts: 18285
Location: Minneapolis - St.Paul Area
Joined: September 2, 2000
Contributor
  Since: May 16, 2021
 Yup, I've battled ground loop issues for over 15 years... I have 115db Oris Horns and 45 SET Monoblocks, so any noise at all whether from a ground loop or a noisy tube will show up. My system is Silent Now.

I tried solving the ground loop problem the 'conventional ways', and improved it, but could not achieve the silence that I have now. The resistor on the amplifier input, which you referred to, did reduce it quite a bit on on one pair of 45 amps that I had, but did nothing on another pair.

The more I studied this problem, the more I found out that very few people really understand it. It only takes a few milivolts on an amplifier different from another component (preamp for instance) and my 115db horns will produce the sound that my amplifiers amplify. Is a ground truly zero volts or could it be .0001 volt -- My Oris Horns know.




 

RE: Good work, posted on April 20, 2021 at 14:21:45
Ralph
Manufacturer

Posts: 4769
Location: Minnesota
Joined: April 24, 2002
 The resistor on the amplifier input, which you referred to, did reduce it quite a bit on on one pair of 45 amps that I had, but did nothing on another pair.

I didn't mention it being at the input FWIW. But we do use this technique.

If it didn't work on one channel, it might be because something was grounding where it shouldn't have been in the other pair of amps? Its logical to assume that if it worked on one pair of amps that an identical pair would behave the same way. That they didn't suggests they were not identical...

 

RE: Good work, posted on April 20, 2021 at 14:33:22
Cut-Throat
Audiophile

Posts: 18285
Location: Minneapolis - St.Paul Area
Joined: September 2, 2000
Contributor
  Since: May 16, 2021
 No these were completely different Monoblocks... And it did not eliminate all of the hum, but reduced it quite a bit on both channels... When I got the new pair of Monoblocks, it had no effect on either channel. (i'm on my third pair of 45 SET Monoblocks now) -- Still own 2 Pair.

I can't remember whether the resistor was on the input or not for sure. Ron Welborne gave me the suggestion (Which was about 10 years ago)...

Edit: -- I just opened up one of my Amplifiers and inspected the Resistor Mod. It was a resistor that was placed in series between the Ground on PS Regulator Board and the Star Ground on the Chassis.




 

The Clarification Was Necessary......., posted on April 20, 2021 at 15:08:37
Todd Krieger
Audiophile

Posts: 37333
Location: SW United States
Joined: November 2, 2000
 Someone could have read your post, and then tried to put a balanced cable between two single-ended jacks (with adapters).........

 

RE: Quite unlikely. (NT), posted on April 22, 2021 at 05:44:50
CG
Audiophile

Posts: 432
Joined: October 11, 2000
 Hmmm...

So, common mode currents only develop when long cables are involved?

 

Page processed in 0.040 seconds.

[ Top Top of Page ] [ Contact Us ] [ Support/Wish List ] [ Copyright © 2024, Audio Asylum, all rights reserved ]
[ General ] [ Speakers ] [ Tubes ] [ Vinyl ] [ Digital ] [ Hi-Rez ] [ Video Asylum ] [ Cables ] [ Tweaks/DIY ] [ Music ] [ Films ]