To XLR or not to XLR

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Comments

  • anhchungdoan
    anhchungdoan Posts: 760
    edited October 2009
    GV#27 wrote: »
    As has been pointed out just having balanced inputs does not make it a balanced amp.The vast majority of amps with balanced inputs use an invertor/summer circuit that converts the balanced signal into one that is a single ended before amplification.

    True balanced designs are a rare and expensive beast because they require two separate but identically matched gain paths, one for the inverted and one for the noninverted halves of the balanced signal.In this way the signal is kept in it's balanced form from input to output.The complete duplication required increases complexity and cost so you will only find this approach on very hi end products.The designers of which will laud the distortion and noise cancelling advantages of these designs but that only applies if they are fed from a balanced input.

    Aswell as the three Bryston unit's I mentioned previously,Krell's FPB series and Pass's Super Symetrical X series are examples of balanced designs.

    I would like to add BAT to the list. I would recommended the following follow-up readings:

    1. Balance Vs. singled-ended- Walrus sytems web-site www.walrus.co.uk/tech/bal.htm)
    2. Balance line technology ( www.dself.dsl.pipex.com/ampins/balanced/balanced.htm)

    I hope this help.
  • anhchungdoan
    anhchungdoan Posts: 760
    edited October 2009
    Sorry guys for the double posts. This old man is ready for bedtime. Enjoy your reading. Cheer!:D
  • anhchungdoan
    anhchungdoan Posts: 760
    edited October 2009
    GV#27 wrote: »
    As has been pointed out just having balanced inputs does not make it a balanced amp.The vast majority of amps with balanced inputs use an invertor/summer circuit that converts the balanced signal into one that is a single ended before amplification.

    True balanced designs are a rare and expensive beast because they require two separate but identically matched gain paths, one for the inverted and one for the noninverted halves of the balanced signal.In this way the signal is kept in it's balanced form from input to output.The complete duplication required increases complexity and cost so you will only find this approach on very hi end products.The designers of which will laud the distortion and noise cancelling advantages of these designs but that only applies if they are fed from a balanced input.

    Aswell as the three Bryston unit's I mentioned previously,Krell's FPB series and Pass's Super Symetrical X series are examples of balanced designs.

    I would like to add BAT to the list. I would recommended the following follow-up readings:

    1. Balance Vs. singled-ended- Walrus sytems web-site www.walrus.co.uk/tech/bal.htm)
    2. Balance line technology ( www.dself.dsl.pipex.com/ampins/balanced.balnaced/htm)

    I hope this help.
  • anhchungdoan
    anhchungdoan Posts: 760
    edited October 2009
    This is actually what I try to look for. Here it is www.avguide.com/blog/balanced-connection-better. Please pay attention to the part of sound dregrading by the using op amp to invert unbalance signal to balanced signal and vise versa....
  • dorokusai
    dorokusai Posts: 25,576
    edited October 2009
    Wow, didn't know all that stuff thanks 2009 member.
    CTC BBQ Amplifier, Sonic Frontiers Line3 Pre-Amplifier and Wadia 581 SACD player. Speakers? Always changing but for now, Mission Argonauts I picked up for $50 bucks, mint.
  • megasat16
    megasat16 Posts: 3,521
    edited October 2009
    This is actually what I try to look for. Here it is www.avguide.com/blog/balanced-connection-better. Please pay attention to the part of sound dregrading by the using op amp to invert unbalance signal to balanced signal and vise versa....

    Wow! Cool! There are answers that leads to nowhere! ;)

    If op amps is sound degrading device, there is very little devices left to fiddle with in Solid State Audio Designs!

    If you despise OP-Amps in audio instruments, you should only run All Things Tubes.

    I have a complete system compose of all Full Balanced Components but I still prefer Single Ended over Balance since Balance doesn't do a thing for me. I also have tons of high end equipments that does not balance input or output but will be most balance designs by a wide margin.

    Anyway, glad that you got your answers and this thread can finally rest!
    Trying out Different Audio Cables is a Religious Affair. You don't discuss it with anyone. :redface::biggrin:
  • reeltrouble1
    reeltrouble1 Posts: 9,312
    edited October 2009
    dorokusai wrote: »
    Wow, didn't know all that stuff thanks 2009 member.

    you got a new bud, not sure how we all managed before.

    True Balanced always trumps unbalanced and in a pinch I use my balanced cables to route out my sink pipes or what have you (get it, in a pinch, pinch one).

    Ricardo, I see you understand very very well, I suspect our tracks will soon meet in the section of the Rabbit Hole I most frequent.

    RT1
  • Systems
    Systems Posts: 14,873
    edited October 2009
    Oh,the sarcasm.:)
    Testing
    Testing
    Testing
  • megasat16
    megasat16 Posts: 3,521
    edited October 2009
    True Balanced always trumps unbalanced and in a pinch I use my balanced cables to route out my sink pipes or what have you (get it, in a pinch, pinch one).

    RT1

    Only if you need to run a balanced cables from SACD in Rabbit Hole Rig to RTT through the walls, under the ground, down the rabbit hole, up the rabbit hole, up the gutters, through the walls, through the attic, through the insulation materials, along the ac lines, twist around the ceiling fans, and down to your Oinker.

    But if you have like 1/2 meter runs and power lines are nowhere near, RCA or XLR doesn't matter. I am talking about true balanced system from CDP to amplifiers.
    Trying out Different Audio Cables is a Religious Affair. You don't discuss it with anyone. :redface::biggrin:
  • reeltrouble1
    reeltrouble1 Posts: 9,312
    edited October 2009
    balanced trumps unbalanced all things equal, of course this is not to say there is not some great unbalanced gear, even in the Loft's Rabbit Hole....everyone should do the research and then decide but I would not recommend the idea be the sole driving source of ones quest for the secret of life.

    BTW I do know the secret of life, but then it is a secret, one day I may reveal it, the secret that is.

    RT1--Tubes Rule
  • reeltrouble1
    reeltrouble1 Posts: 9,312
    edited October 2009
    GV#27 wrote: »
    Oh,the sarcasm.:)

    yea, ain't it Grand........:D

    RT1
  • CoolJazz
    CoolJazz Posts: 572
    edited October 2009
    megasat16 wrote: »
    But if you have like 1/2 meter runs and power lines are nowhere near, RCA or XLR doesn't matter. I am talking about true balanced system from CDP to amplifiers.
    It can if you plug into two different outlets. :p Just to point it out!

    Question for the "has to be balanced all the way through" idea. If you're not going to have an "extra stage" to accomplish the common mode reject (let's say on the amplifier), then what is the advantage and where does the advantage come from for being fully balanced? :eek:

    CoolJazz
    A so called science type proudly says... "I do realize that I would fool myself all the time, about listening conclusions and many other observations, if I did listen before buying. That’s why I don’t, I bought all of my current gear based on technical parameters alone, such as specs and measurements."

    More amazing Internet Science Pink Panther wisdom..."My DAC has since been upgraded from Mark Levinson to Topping."
  • megasat16
    megasat16 Posts: 3,521
    edited October 2009
    BTW I do know the secret of life, but then it is a secret, one day I may reveal it, the secret that is.

    RT1--Tubes Rule

    You are revealing the secret of life daily in your sig. What more secrets can there be? ;)
    Trying out Different Audio Cables is a Religious Affair. You don't discuss it with anyone. :redface::biggrin:
  • megasat16
    megasat16 Posts: 3,521
    edited October 2009
    CoolJazz wrote: »
    It can if you plug into two different outlets. :p Just to point it out!

    Question for the "has to be balanced all the way through" idea. If you're not going to have an "extra stage" to accomplish the common mode reject (let's say on the amplifier), then what is the advantage and where does the advantage come from for being fully balanced? :eek:

    CoolJazz

    I would be so dare to say the captive PS cords with shielding and the Power Outlets with noise filters will take care of most problems XLR can offer anyway. :D

    I tried full balanced all the way to the amps and does not notice anything for me. May be I am not getting your question of "extra stage" in the amps to reject CMRR? :o
    Trying out Different Audio Cables is a Religious Affair. You don't discuss it with anyone. :redface::biggrin:
  • anhchungdoan
    anhchungdoan Posts: 760
    edited October 2009
    balanced trumps unbalanced all things equal, of course this is not to say there is not some great unbalanced gear, even in the Loft's Rabbit Hole....everyone should do the research and then decide but I would not recommend the idea be the sole driving source of ones quest for the secret of life.

    BTW I do know the secret of life, but then it is a secret, one day I may reveal it, the secret that is.

    RT1--Tubes Rule


    RT!- Tubes Rule. I cannot and do not want to get into this SS vs. Tubes stuff but 2 of my favourite intergrated amps are the SLI 80 and 400 xi ( Harmotic Tech cabling, Paradigm S2v2) . :)
  • CoolJazz
    CoolJazz Posts: 572
    edited October 2009
    The "extra stage" is referring to is from the link here to a nice Robert Harley article...
    This is actually what I try to look for. Here it is www.avguide.com/blog/balanced-connection-better. Please pay attention to the part of sound dregrading by the using op amp to invert unbalance signal to balanced signal and vise versa....

    The question I'm posing is...if you leave out the common mode reject stage on the input, then what advantages do the fully balanced amp give you?
    A so called science type proudly says... "I do realize that I would fool myself all the time, about listening conclusions and many other observations, if I did listen before buying. That’s why I don’t, I bought all of my current gear based on technical parameters alone, such as specs and measurements."

    More amazing Internet Science Pink Panther wisdom..."My DAC has since been upgraded from Mark Levinson to Topping."
  • anhchungdoan
    anhchungdoan Posts: 760
    edited October 2009
    CoolJazz wrote: »
    The "extra stage" is referring to is from the link here to a nice Robert Harley article...



    The question I'm posing is...if you leave out the common mode reject stage on the input, then what advantages do the fully balanced amp give you?

    As you have been aware of that I am not a very technical oriented guy as I stated at the beginning of the thread. I will have to wait for some technical guy to chime in but these are mainly my points as follows:

    1. You have seen so many so-called audiophile concerning about increase of resistance and inductance in patching or extending the length of their speaker cables. As the you read the scenario where the CD/ preamp/ amp by Robert Harley, the process of converting the unbalanced signal to balanced signal where the circuit is subject to 4 additional active amplifiers stages, I have to agree with Robert that it is INEVITABLE (in his second scenario) that there is a degrading of the SQ. So let's relate these 2 cases in a logical thinking about concerning the degrading SQ.

    2.Agree or not, the end-user walks to a hi-end store to audition a pair of pre/pro & amp. Let's pick one brand in no particular flame intended but this was actual experience I have lived thru ( an friend who owned a hi-end audio store that has went bellied-up several years ago). Let's say the Anthem . The end-users "WOWED" at these balanced output/input and besides the fact that he loved the sound but these so-called balanced input/ouput weighted heavily on his decision making ( among the uninformed buyer s)
    I was there but it was none of my business to tell the end-user that these amps did not have actually balance topology but at the same token I felt the consumer had been mislead.

    Not to side step the subject, back in the 2003 , the highly regarded Atoll CDP which was sold for $1,000.00 was nothing but a re-badged of the $70.00 Technics CDP with some revamped power supply.

    That's the purpose of my post.
  • megasat16
    megasat16 Posts: 3,521
    edited October 2009
    Eh...the gurus at AVguide overlooked the most important part, I say! :D
    Trying out Different Audio Cables is a Religious Affair. You don't discuss it with anyone. :redface::biggrin:
  • anhchungdoan
    anhchungdoan Posts: 760
    edited October 2009
    megasat16 wrote: »
    Eh...the gurus at AVguide overlooked the most important part, I say! :D


    I do not think this is the case but rather the case of manipulation of the circuit with the xtra unnessary stage that will degrading the SQ. If it's a unbalanced design why not just leave it the way it is by providing the single-ended input/output.

    For most of the H/T application for home residential , the distance among the CDP/DVD, Pre-Processor, amps are not beyond 15 / 25 feet of each others, so what is the significant factor(s) to provide the XLR connections on a unbalanced circuit design ?
  • Barefoot
    Barefoot Posts: 149
    edited October 2009
    I've never heard one difference between XLR vs RCA. Ever. But I still use XLR if available. Why? Dunno.
  • megasat16
    megasat16 Posts: 3,521
    edited October 2009
    I do not think this is the case but rather the case of manipulation of the circuit with the xtra unnessary stage that will degrading the SQ. If it's a unbalanced design why not just leave it the way it is by providing the single-ended input/output.

    For most of the H/T application for home residential , the distance among the CDP/DVD, Pre-Processor, amps are not beyond 15 / 25 feet of each others, so what is the significant factor(s) to provide the XLR connections on a unbalanced circuit design ?

    There is a song I heard before but don't know what's the name of it or the singer.

    [Do you know see what I see...
    Do you know what I know....
    Do you hear what I hear (may be I added this line)]

    Anyway, the question I like to ask is


    Do you know what you need to hear and do you know if you are hearing it?

    Do you know what you shouldn't be hearing and do you know you are not hearing it or it's so minute that your brain can't process or comprehend?

    or Do you tweak your system to sounds good and deviates from the natural sound it was meant to be heard the way it? If you are making the sucking sound to be sweet, think about it one more time.

    Tubes, Transistors, OPamps, resistors, capacitors, etc. all can be good or evil. All depends on how it's used and what consideration is taken place.

    AVguide saying one extra stage with opamp is degrading sound! Running 10+ feet of signal cables can degrade sounds even more. If signal integrity is important, just put the components closer together and use shielded Power cables and good RCA cables. Opamps can sound damn good if it's implemented properly.

    True Balanced or not, XLR can provide Common Mode Rejection for longer cable runs. The other part is marketing hype to scoop more money out from your pocket. If you are not educated consumer, you are expected to pay to learn.
    Trying out Different Audio Cables is a Religious Affair. You don't discuss it with anyone. :redface::biggrin:
  • anhchungdoan
    anhchungdoan Posts: 760
    edited October 2009
    megasat16 wrote: »
    There is a song I heard before but don't know what's the name of it or the singer.

    [Do you know see what I see...
    Do you know what I know....
    Do you hear what I hear (may be I added this line)]

    Anyway, the question I like to ask is


    Do you know what you need to hear and do you know if you are hearing it?

    Do you know what you shouldn't be hearing and do you know you are not hearing it or it's so minute that your brain can't process or comprehend?

    or Do you tweak your system to sounds good and deviates from the natural sound it was meant to be heard the way it? If you are making the sucking sound to be sweet, think about it one more time.

    Tubes, Transistors, OPamps, resistors, capacitors, etc. all can be good or evil. All depends on how it's used and what consideration is taken place.

    AVguide saying one extra stage with opamp is degrading sound! Running 10+ feet of signal cables can degrade sounds even more. If signal integrity is important, just put the components closer together and use shielded Power cables and good RCA cables. Opamps can sound damn good if it's implemented properly.

    True Balanced or not, XLR can provide Common Mode Rejection for longer cable runs. The other part is marketing hype to scoop more money out from your pocket. If you are not educated consumer, you are expected to pay to learn.

    I entered to this mi-end/hi-end in the late 70s following the footsteps of a fellow at work. Fortunately, I have a few acquantaces who ran some brick and motar audio dealers, I have learned and as you say I have paid the price to learn to differentiate the myth/ the hype and the truth.

    Life is a learning process indeed but also to share one's mistake so the others will learn and avoid to make the same mistake. Some do not give a crap and some will. I am sorry if I offend any dealer or marketing rep. , as they say, there is no good deed goes unpunished.

    Let's close this thread for now. :(
  • Systems
    Systems Posts: 14,873
    edited October 2009
    CoolJazz wrote: »
    Question for the "has to be balanced all the way through" idea. If you're not going to have an "extra stage"
    In the case of an amp with just a balanced input(not "fully balanced") there would have to be an inversion /summing stage at the input.Many times the summing of the inverted and noninverted signal is done at the differential inputs so no extra cicuitry is needed.
    then what is the advantage and where does the advantage come from for being fully balanced?
    An amplifier designed with the fully balanced approach from input - output (ie. Pass's Super Symmetry designs) can have condierably lower measured distortion and noise if it is fed from a balanced source.So just as with the noise canceling provided by the differential signal in a balanced cable, differential amplification can reduce distortion generated within the amp.This even allows the designer to use less feedback etc.

    Using balanced cables with "non" fully balanced equipment may or may not offer sonic advantages for home users with short cable run's.But it is very possible atleast from a measurement stand point that using equipment designed with the fully balanced approach from input output and using balanced cables could offer sonic advantages vs running them single ended..
    Testing
    Testing
    Testing
  • reeltrouble1
    reeltrouble1 Posts: 9,312
    edited October 2009
    its what you dont hear with a fully balanced system that matters most, not what you do.

    RT1
  • TECHNOKID
    TECHNOKID Posts: 4,298
    edited October 2009
    its what you dont hear with a fully balanced system that matters most, not what you do.

    RT1
    Exactly, noise always been a problem in circuits and cables and balanced seems to be the best way of eliminating it. However, part of the key is also at the pre-amp since the noise ratio is more important at that point since the signal is smaller, with proper elimantion/overriding of the noise at the pre-amp and once amplification has started the noise is so insignificant that it is barely perceptible.

    A good example of such are mixing consoles; mixing unbalanced cables are usally a nightmare and can hardly be eliminated unless using ground lift (Lo to ground). The mistake most do is to ignore the Lo, leaving it un-connected which can also act as an antenna and pick-up even more un-wanted noise.

    Since noise is naturally present one must "SOLO/PFL" each inputs in order to override the noise at the primary stage. While balanced connections are a plus, the pre-amp is even more important. Mechanical (faders on a mixer) or electronic circuits (in separate pre-amps or AVR pre-amps) are the key to the overall SQ. Let's just keep in mind, "garbage in = garbage out, you can use all of the XLR cables you want but if the input is bad from the start, all of the expensive HI-FI gear will replicate with precision the in-coming signal which is actually garbage :eek:

    Cheers!
    TK
    DARE TO SOAR:
    “Your attitude, almost always determine your altitude in life” ;)
  • reeltrouble1
    reeltrouble1 Posts: 9,312
    edited October 2009
    Everything Matters.....Madmax--also known as the The Oracle of Audio.

    RT1
  • CoolJazz
    CoolJazz Posts: 572
    edited October 2009
    Great answers GV!

    I was thinking of the phase splitting stage and the level difference of balanced (since the waveforms going opposite directions means twice the voltage). This greater voltage means you're that much further above any received noise before the cancellation in the differential input stage. This is exactly as Technokid is referring to. Greater input means less gain necessary, which as GV says means things like maybe less feedback.

    Lots of decisions are made by the designer, which may be rooted in belief, result, cost, or just plain making something different. I was trying in this thread to expose some reasons a particular piece might have a balanced in while not being fully balanced. And it not be done just to fool somebody that doesn't know better. How good an unbalanced or balanced design actually sounds still boils down to how well it's executed.

    In case anybody was thinking I was in favor of balanced interconnect or against totally balanced design, no not really. I was trying to point out that there is reasons to design either way and it has a lot to do with cost's and perceived benefits which has tremendous impact at the point of purchase!

    Great thread!

    CoolJazz
    A so called science type proudly says... "I do realize that I would fool myself all the time, about listening conclusions and many other observations, if I did listen before buying. That’s why I don’t, I bought all of my current gear based on technical parameters alone, such as specs and measurements."

    More amazing Internet Science Pink Panther wisdom..."My DAC has since been upgraded from Mark Levinson to Topping."
  • TECHNOKID
    TECHNOKID Posts: 4,298
    edited October 2009
    rather old paper but still interesting to understand balanced circuits and CMRR:

    http://www.epanorama.net/pdf_redirect.php?url=http://www.jensen-transformers.com/an/ingenaes.pdf
    DARE TO SOAR:
    “Your attitude, almost always determine your altitude in life” ;)
  • CoolJazz
    CoolJazz Posts: 572
    edited October 2009
    Yes, great paper Techno.

    Another Whitlock paper that was a bigger eye opener for me was one that he wrote about how good and effective transformer coupling actually is. The only reason we don't use more iron today is cost and weight. In the real world, it almost always actually works better.

    As a guy that spent many years hearing how IC's are so good and give us "DC to light" performance and that we have to get rid of all that old transformer stuff, that paper was a real show stopper. Wish I could find it to provide a link, but I haven't seen it for years now.

    Wish I could put my hands on only a tiny part of that "old iron" that got trashed with such glee!!

    CoolJazz
    A so called science type proudly says... "I do realize that I would fool myself all the time, about listening conclusions and many other observations, if I did listen before buying. That’s why I don’t, I bought all of my current gear based on technical parameters alone, such as specs and measurements."

    More amazing Internet Science Pink Panther wisdom..."My DAC has since been upgraded from Mark Levinson to Topping."
  • reeltrouble1
    reeltrouble1 Posts: 9,312
    edited October 2009
    CoolJazz wrote: »
    The only reason we don't use more iron today is cost and weight. In the real world, it almost always actually works better.

    CoolJazz


    ah, I sense great things for you at Club Polk CoolJ.

    RT1