A novel (and obvious) test of speaker cables

Discussion in 'Accessories, Cables, and Remotes' started by Rob Bird, Dec 7, 2004.

  1. Rob Bird

    Rob Bird Agent

    Joined:
    Nov 21, 2004
    Messages:
    47
    Likes Received:
    0
    Trophy Points:
    0
    Today, after talking about various commonly held factors regarding speaker cables, it dawned on me that as much as audiophiles pride themselves on being discriminating listeners, most of the second order effects (meaning, not Resistance, Inductance or Capacitance) haven't been well tested. Yes, in the lab we know that stranded wires can look like complex mV diode arrays, but can we actually HEAR it? Can we actually hear the skin effect in huge, solid (or nearly solid) conductors?

    So what is the novel idea? The idea is for me to build a couple different sets of cables that should totally violate the "laws" of cable building. These will be tested by me in a totally non-double blind fashion with the intent of choosing cables which are so "bad" that they either have an obious effect or not.

    The current (!) comparison will be:
    1. My reference...a set of cat5 speaker cables I built and reviewed on audioreview in 1998 (original posting, actually).
    2. A set of 00 gauge speaker cables made from pvc insulated copper grounding wire. These will be widely spaced to form a very low capacitance version (high inductance).
    3. A set of 00 gauge speaker cables made from pvc insulated copper grounding wire. These will be closely spaced to form a high capacitance version (low inductance). 2. and 3. will be used to demonstrate the effect of skin effect.
    4. A set of high gauge aluminum cables. I haven't picked out anything yet, but will post back what was chosen. These will be tested against the corresponding copper geometry above (wide space vs. wide space, etc.).
    5. Closely spaced version of 4.
    6. A set of cables made from 16 gauge monster cable zip cord.
    7. A set of cables made from coated steel security bike lock cable. I will measure the approximate gauge.

    I will post the Resistance, Inductance and Capacitance of each as measured by my test equipment. Each will be terminated as best as possible. It's going to be a neat trick trying to terminate some of these into spades. I may have to make some compromises here, but will be as attentive as possible. I will also compare each on some familiar HT tracks (things like finding Nemo).

    Back to the lab, and hopefully back later with some interesting results [​IMG]
    Rob
    Rob
     
  2. Rob Bird

    Rob Bird Agent

    Joined:
    Nov 21, 2004
    Messages:
    47
    Likes Received:
    0
    Trophy Points:
    0
    Ok, an update:

    1. The aluminum cable wasn't available, so I've skipped it in the test.
    2. I've also skipped the steel cable...in my haste I initially forgot that it's magnetic :/
    3. The 2/0 cable is so hard to form into shapes that it's also not going to be very practical to do the side-by-side configuration. At the moment, the +/- are about a foot apart.
    4. The connections on the 2/0 cable are made via copper compression lugs with a very short (1.5") 18 gauge lead wire. I have wrapped the wire around the mounting posts and cranked them down to hand tightness.

    So what are we down to?
    1. 1 pair of DIY Cat 5 braided cables
    2. 1 pair of 2/0 gauge wire, loosely separated

    I'm settling in to listen now. I've picked a couple packages from Finding Nemo, and some Ani Difranco acoustic recordings that I use to test speakers.
     
  3. Rob Bird

    Rob Bird Agent

    Joined:
    Nov 21, 2004
    Messages:
    47
    Likes Received:
    0
    Trophy Points:
    0
    Initial impressions:

    - 2/0 cables: They sound fine! In terms of dynamics, they are as good as my reference cables. There is no spit, hiss, fizzle or anything else in the high end. Imaging is rock solid. There is some weird, but mild, hollowness in voices and mid-high frequency sounds. They actually sound out of phase in these regions, that's the initial feeling in my ear.
    - Cat 5 cables: These continue to be as good as ever. There seems to just be more seemless coherence all around compared to the big ones.

    During the Nemo viewing, I watched a few scenes:
    - The submarine scene
    - The jellyfish forest
    - The initiation

    All of the special, or critical points in each of these scenes was portrayed just fine. The voices in the initiation seemed a bit weird to me on the 2/0's. Again, more of the feeling that something was out of phase. I am not saying they were, just that it sounded that way.

    On to music.
     
  4. Rob Bird

    Rob Bird Agent

    Joined:
    Nov 21, 2004
    Messages:
    47
    Likes Received:
    0
    Trophy Points:
    0
    Ahhh, Ani live. There is so much to hear in these recordings. Here is where I could detect more difference between the 2/0's and the Cat 5 cables. These recordings are not dynamic at all, but there are lots of little sounds that get miked...shoes moving on the floor, the smack her mouth makes when it opens, etc.

    2/0's - Crystal clear, but her voice somehow sounded thin. The shoes shuffling actully didn't sound like shoes, but more like a chair sliding, and there was a distinct lack of resonance in her voice when she's doing the close mike work. The cables did actually seem louder, but the variance on my SPL meter was only about 1/4 of a db, and that could be something attributable to the meter.
    Cat 5's - Again, my impression is that the cable really isn't doing anything to the sound. The shoes sound like shoes, and the close mike work just seems to open a vein.

    In the end, I'd say that the Cat 5 DIY is probably 1-3% better _in listening perception_ than the other ridiculous cables, assuming that the skin effect isn't causing some strange phase shifting, or something more serious.

    I'll keep listening, and see if films like Master and Commander sound any better. At least it's been interesting to test it for myself.

    Rob
     
  5. JimPeitersen

    JimPeitersen Second Unit

    Joined:
    Dec 7, 2001
    Messages:
    470
    Likes Received:
    0
    Trophy Points:
    0
    Rob,
    Did you consider the "traditional" "non-traditional" wires - romex (you pick the guage) and metal coat hangers? I would be interested to see what you think about either.
    JP
     
  6. Rob Bird

    Rob Bird Agent

    Joined:
    Nov 21, 2004
    Messages:
    47
    Likes Received:
    0
    Trophy Points:
    0
    lol. Barb or not, the 2/0 gauge power cord definetly blows the absurdity of romex away. It's basically giant THHN. I need to take some pics, actually, a friend of mine thought they were snakes.

    I guess the end result is just that resistance is definetly a primary factor in the success of a speaker cable, and that secondary effects are audible at extremes.

    And no, I'm not dealing with coat hangers...they are again, magnetic. I think any large conductor would probably have similar results (although aluminum, which would be even fatter at the same conductivity would be even worse with this phasing issue I'm thinking is attributable to the skin depth in a conductor that large).
    Rob
     

Share This Page