Blind Test of Power Cords

Discussion in 'High End Audio' started by Steven Sullivan, Dec 7, 2004.

  1. procedures and results here:

    http://www.hometheaterhifi.com/volume_11_4/feature-article-blind-test-power-cords-12-2004.html

    interesting because, in this case, a reviewer (Jason Victor Serinus) who'd
    positively reviewed the 'sound' of expensive power cords ($2500 Nordost
    Valhalla -- which , he reported, only sounded good after break-in) ,
    participated in the ABX, and wrote up the report.

    Mr. Serinus had also praised the Bedini Dual Beam UltraClarifier, as sheer
    a piece of quackery as ever was marketed to audiophiles.

    Even though his acceptance of the scientific method, and the results
    obtained thereby, appears grudging at best, I trust that henceforth he
    will be more cautious in drawing conclusions about audible difference from
    unconctolled sighted comparison.
     
    Steven Sullivan, Dec 7, 2004
    #1
    1. Advertisements

  2. What the heck was the logic behind expensive power cords anyway? I can't
    begin to fathom why, after traveling for miles and miles through wire
    that was provided by the lowest bidder, the last three feet would have
    some sort of magical difference.

    Mike
     
    Michael Dombrowski, Dec 8, 2004
    #2
    1. Advertisements

  3. Steven Sullivan

    outsor Guest

    "What the heck was the logic behind expensive power cords anyway? I can't
    begin to fathom why, after traveling for miles and miles through wire that
    was provided by the lowest bidder, the last three feet would have some
    sort of magical difference."

    After having eliminated all of the bits and parts by applying tweeks to
    them, powercord wire was what was left. One real area of tweeky audio was
    the turntable where individual action might hit upon some previously
    unknown trick/technique which addressed it's many inherent sources of
    problems in translating mechanical motion into electrical signal. With
    the advent of the cd that world collapsed for most audiophiles. I think
    one will find that is the era when wire came into the picture as all that
    energy was adapted to finding something to replace the previous area where
    an individual could make a difference by tweeking a complex system.
     
    outsor, Dec 8, 2004
    #3
  4. Steven Sullivan

    Tat Chan Guest

    Michael Dombrowski wrote:

    I read this analogy on a hi-fi forum (most definitely non technical!)
    where the posters believed in such things.

    It went something like

    "Adding a filter to the tap in the kitchen sink for drinking water helps
    remove the impurities accumulated along the way from the water source to
    the home".
     
    Tat Chan, Dec 8, 2004
    #4
  5. Steven Sullivan

    Andrew Haley Guest

    You're being too unkind.

    This author seems to have conducted an exemplary experiment and been
    brutally honest about the result. It's hard to eat humble pie in
    public, and to do so is worthy of high praise.

    One fault of the article is that it gives time to the "Are Blind Tests
    Reliable?" question, which is little more than solipsism. How else
    are we to discover whether a blind test is reliable, except with
    another blind test? But that is a small fault in the context of the
    whole piece.

    Andrew.
     
    Andrew Haley, Dec 9, 2004
    #5
  6. Steven Sullivan

    John Walton Guest

    You can remove the water filter and see the crud which travels in the pipes.

    Power cords do a "de minimis" amount of filtering, after all they do have
    inductance and capacitance.

    The problem with crud on your power line is better dealt with an EMI
    filter -- the type used in a switching power supply -- if you snapshot your
    mains voltage with a spectrum analyzer over the course of a day you can see
    the perturbations -- harmonics of the 60Hz, noise, spikes etc. -- all
    interjected at various hours. While a SMPS filter main purpose is to prevent
    EMI from being radiated back to the wall outlet it works in both directions.

    Under normal circumstances I reject the notion of "regulation" the +/- rails
    of a power amplifier -- but in the case of a really noisy mains voltage an
    EMI filter and linear regulation (with high speed/low noise error amps like
    the AD825 or AD797) will make a difference -- .

    At any rate, if power lines were so important companies like Keithley
    Instruments or Agilent would pack them with their femto-ammeters.
     
    John Walton, Dec 9, 2004
    #6
  7. Steven Sullivan

    Pooh Bear Guest

    Getting rich quick !
    It doesn't. Not least ( logically ) for the reason you state - but also because any decent power
    supply in audio gear has no influence on the audio path in the way suggested by the snake oil
    merchants. It ( the psu ) might badly influence the sound of some really cheap Asian shit computer
    speakers or whatever - but no esoteric power cord will improve that anyway.

    It's just pandering to the 'pseudo-science' believers and relegates real science to the bin. It's
    expedient for magazines not to tell the truth since that would diminish their advertising revenue.


    Graham
     
    Pooh Bear, Dec 11, 2004
    #7
  8. Steven Sullivan

    Pooh Bear Guest

    Actually, adding an EMI ( electro magnetic interference ) filter may not be a
    bad thing if you have a noisy mains supply. No bad thing to have a surge
    arrestor too. Transients - typically 'spikes' - on the ac supply can indeed
    break into the audio path and cause clicks. These items will cost you maybe
    $25 if purchased sensibly. That's an entirely different matter from power
    cords though.


    Graham
     
    Pooh Bear, Dec 11, 2004
    #8
  9. Steven Sullivan

    ---MIKE--- Guest

    You can accomplish both surge protection and EMI filtering by using a
    "Brick Wall" surge protector. For more information, go to
    http://www.brickwall.com. I own one but am not in any way connected
    with the company.


    ---MIKE---
     
    ---MIKE---, Dec 12, 2004
    #9
  10. Steven Sullivan

    rlichter Guest


    The vendor for Brick Wall, Zero Surge, make a virtually identical set
    of series surge protectors for considerably less money.
     
    rlichter, Feb 1, 2005
    #10
    1. Advertisements

Ask a Question

Want to reply to this thread or ask your own question?

You'll need to choose a username for the site, which only take a couple of moments (here). After that, you can post your question and our members will help you out.