• Modern wire sizing.

    From David Paste@pastedavid@gmail.com to uk.d-i-y on Sun Feb 22 18:22:36 2026
    From Newsgroup: uk.d-i-y

    I know nowt.

    I have a roll of "2x42 speaker cable" which indeed has 42 strands of
    very thin copper wire in each cable (?), and there are indeed two of
    them, joined together in a figure of 8 way.

    Searching for this, another site suggests that the strands are "0.19mm",
    would this be the diameter? Or the radius? I'm guessing diameter, but
    you all know what assumptions are like.

    This same site also states that the wire is 1.32mm^2 and I am assuming
    that this is for each 42 strands-in-total wire, not for both the wires.

    So are modern multi-strand wires all made from 0.19 mm strands, bundled
    to whatever size is necessary for the wire?

    I am not sure of the correct nomenclature with regards to the individual strands, the greater wire within the insulation, and the name for the
    wire made from two (or more, I suppose) insulated wires joined together (cables?), so please feel free to ridicule my ignorance.

    Thanks in advance.
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  • From Cursitor Doom@cd@notformail.com to uk.d-i-y on Sun Feb 22 18:25:13 2026
    From Newsgroup: uk.d-i-y

    On Sun, 22 Feb 2026 18:22:36 +0000, David Paste <pastedavid@gmail.com>
    wrote:

    I know nowt.

    I have a roll of "2x42 speaker cable" which indeed has 42 strands of
    very thin copper wire in each cable (?), and there are indeed two of
    them, joined together in a figure of 8 way.

    Searching for this, another site suggests that the strands are "0.19mm", >would this be the diameter? Or the radius? I'm guessing diameter, but
    you all know what assumptions are like.

    This same site also states that the wire is 1.32mm^2 and I am assuming
    that this is for each 42 strands-in-total wire, not for both the wires.

    So are modern multi-strand wires all made from 0.19 mm strands, bundled
    to whatever size is necessary for the wire?

    I am not sure of the correct nomenclature with regards to the individual >strands, the greater wire within the insulation, and the name for the
    wire made from two (or more, I suppose) insulated wires joined together >(cables?), so please feel free to ridicule my ignorance.

    Thanks in advance.

    Cross-sectional area, I would guess. No doubt someone can confirm or
    correct that as the case may be.
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  • From Theo@theom+news@chiark.greenend.org.uk to uk.d-i-y on Sun Feb 22 18:46:24 2026
    From Newsgroup: uk.d-i-y

    David Paste <pastedavid@gmail.com> wrote:
    I know nowt.

    I have a roll of "2x42 speaker cable" which indeed has 42 strands of
    very thin copper wire in each cable (?), and there are indeed two of
    them, joined together in a figure of 8 way.

    Searching for this, another site suggests that the strands are "0.19mm", would this be the diameter? Or the radius? I'm guessing diameter, but
    you all know what assumptions are like.

    That's the diameter.

    This same site also states that the wire is 1.32mm^2 and I am assuming
    that this is for each 42 strands-in-total wire, not for both the wires.

    Correct. Calculating the area via pi.r^2:

    r=0.19/2
    pi*(0.19/2)^2 = 0.02835
    42*0.02835 = 1.19 mm2

    which is near enough.

    So are modern multi-strand wires all made from 0.19 mm strands, bundled
    to whatever size is necessary for the wire?

    No, they use all kinds of sizes.

    I am not sure of the correct nomenclature with regards to the individual strands, the greater wire within the insulation, and the name for the
    wire made from two (or more, I suppose) insulated wires joined together (cables?), so please feel free to ridicule my ignorance.

    Usually stranded wires are written as 7/0.1 which means 7 strands of 0.1mm diameter wire. You can get many different combinations of diameter and
    number of strands. Then of course you get multicore cable which might have
    9 cores each being of 7/0.1mm.

    Electrical power cable is instead measured by the mm2 cross-sectional area, being either class 1 (solid core), class 2 stranded (eg 7 strands in normal domestic sizes), or class 5 or 6 flexible (many more strands): https://tr.prysmian.com/en/media/technical-article/conductor-types-in-cables

    - so for example Twin and Earth cable is 2x2.5+1.5 which means two cores of
    2.5mm2 plus an earth core of 1.5mm2 (all solid)

    Then you have all the different types of cable which usually relates to the insulation and the makeup of the cable rather than the conductors.

    And Then you have Americans, who measure it all in AWGs ('gauge') instead.
    (and their 14/2 means two conductors of 14 awg each)

    Theo
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  • From Andrew@Andrew97d@btinternet.com to uk.d-i-y on Sun Feb 22 19:20:14 2026
    From Newsgroup: uk.d-i-y

    On 22/02/2026 18:22, David Paste wrote:
    I know nowt.

    I have a roll of "2x42 speaker cable" which indeed has 42 strands of
    very thin copper wire in each cable (?), and there are indeed two of
    them, joined together in a figure of 8 way.

    Searching for this, another site suggests that the strands are "0.19mm", would this be the diameter? Or the radius? I'm guessing diameter, but
    you all know what assumptions are like.

    This same site also states that the wire is 1.32mm^2 and I am assuming
    that this is for each 42 strands-in-total wire, not for both the wires.

    So are modern multi-strand wires all made from 0.19 mm strands, bundled
    to whatever size is necessary for the wire?

    I am not sure of the correct nomenclature with regards to the individual strands, the greater wire within the insulation, and the name for the
    wire made from two (or more, I suppose) insulated wires joined together (cables?), so please feel free to ridicule my ignorance.

    Thanks in advance.

    This is speaker wire, for low voltage usage, so just don't ever
    use it for mains voltage. It is multi-stranded primarily for
    flexibility (likely to vibrate under the influence of the
    speaker), and HiFi 'purists' might say there is a electronic
    reason for using multi-stranding instead of solid core (or maybe
    the opposite, I wouldn't know).
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  • From The Natural Philosopher@tnp@invalid.invalid to uk.d-i-y on Sun Feb 22 20:30:46 2026
    From Newsgroup: uk.d-i-y

    On 22/02/2026 19:20, Andrew wrote:
    This is speaker wire, for low voltage usage, so just don't ever
    use it for mains voltage. It is multi-stranded primarily for
    flexibility (likely to vibrate under the influence of the
    speaker), and HiFi 'purists' might say there is a electronic
    reason for using multi-stranding instead of solid core (or maybe
    the opposite, I wouldn't know).

    Technically it was known as doorbell wire.

    Definitely OK up to midfi levels for audio. Bigger stranded silicone
    cable is made for serious power levels and best bass damping or for any
    high current wiring needing low resistance and good mechanical flexibility

    I have used it for light pendants and (slaps wrist) mains table lamps as
    well
    --
    Climate Change: Socialism wearing a lab coat.

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  • From Mike Humphrey@mail@michaelhumphrey.me.uk to uk.d-i-y on Mon Feb 23 09:20:25 2026
    From Newsgroup: uk.d-i-y

    On Sun, 22 Feb 2026 20:30:46 +0000, The Natural Philosopher wrote:
    I have used it for light pendants and (slaps wrist) mains table lamps as
    well

    There was a version rated for mains voltage - twin "shotgun" cores but
    with thicker insulation than the audio version - that was quite common at
    one time for things like lamps. Not allowed now as the regs require two
    layers of insulation.

    Mike
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  • From Simon Simple@nothanks@nottoday.co.uk to uk.d-i-y on Mon Feb 23 09:57:19 2026
    From Newsgroup: uk.d-i-y

    On 22/02/2026 18:46, Theo wrote:
    David Paste <pastedavid@gmail.com> wrote:
    I know nowt.

    I have a roll of "2x42 speaker cable" which indeed has 42 strands of
    very thin copper wire in each cable (?), and there are indeed two of
    them, joined together in a figure of 8 way.

    Searching for this, another site suggests that the strands are "0.19mm",
    would this be the diameter? Or the radius? I'm guessing diameter, but
    you all know what assumptions are like.

    That's the diameter.

    This same site also states that the wire is 1.32mm^2 and I am assuming
    that this is for each 42 strands-in-total wire, not for both the wires.

    Correct. Calculating the area via pi.r^2:

    r=0.19/2
    pi*(0.19/2)^2 = 0.02835
    42*0.02835 = 1.19 mm2

    which is near enough.

    <xxx>

    42/0.2 is a common speaker wire size. That gives 1.32 mm^2.
    --
    SS

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  • From alan_m@junk@admac.myzen.co.uk to uk.d-i-y on Mon Feb 23 12:05:40 2026
    From Newsgroup: uk.d-i-y

    On 22/02/2026 18:46, Theo wrote:
    David Paste <pastedavid@gmail.com> wrote:
    I know nowt.

    I have a roll of "2x42 speaker cable" which indeed has 42 strands of
    very thin copper wire in each cable (?), and there are indeed two of
    them, joined together in a figure of 8 way.

    Searching for this, another site suggests that the strands are "0.19mm",
    would this be the diameter? Or the radius? I'm guessing diameter, but
    you all know what assumptions are like.

    That's the diameter.

    This same site also states that the wire is 1.32mm^2 and I am assuming
    that this is for each 42 strands-in-total wire, not for both the wires.

    Correct. Calculating the area via pi.r^2:

    r=0.19/2
    pi*(0.19/2)^2 = 0.02835
    42*0.02835 = 1.19 mm2

    which is near enough.

    So are modern multi-strand wires all made from 0.19 mm strands, bundled
    to whatever size is necessary for the wire?

    No, they use all kinds of sizes.

    I am not sure of the correct nomenclature with regards to the individual
    strands, the greater wire within the insulation, and the name for the
    wire made from two (or more, I suppose) insulated wires joined together
    (cables?), so please feel free to ridicule my ignorance.

    Usually stranded wires are written as 7/0.1 which means 7 strands of 0.1mm diameter wire. You can get many different combinations of diameter and number of strands. Then of course you get multicore cable which might have
    9 cores each being of 7/0.1mm.

    Electrical power cable is instead measured by the mm2 cross-sectional area, being either class 1 (solid core), class 2 stranded (eg 7 strands in normal domestic sizes), or class 5 or 6 flexible (many more strands): https://tr.prysmian.com/en/media/technical-article/conductor-types-in-cables

    - so for example Twin and Earth cable is 2x2.5+1.5 which means two cores of
    2.5mm2 plus an earth core of 1.5mm2 (all solid)

    Then you have all the different types of cable which usually relates to the insulation and the makeup of the cable rather than the conductors.

    And Then you have Americans, who measure it all in AWGs ('gauge') instead. (and their 14/2 means two conductors of 14 awg each)

    There is a variation in what the cable wires may be made from. Copper
    or Copper plated Steel or Aluminium

    Also the fake cables where the numbers may be a work of fiction.
    --
    mailto : news {at} admac {dot} myzen {dot} co {dot} uk
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  • From Paul@nospam@needed.invalid to uk.d-i-y on Mon Feb 23 09:15:28 2026
    From Newsgroup: uk.d-i-y

    On Sun, 2/22/2026 2:20 PM, Andrew wrote:
    On 22/02/2026 18:22, David Paste wrote:
    I know nowt.

    I have a roll of "2x42 speaker cable" which indeed has 42 strands of very thin copper wire in each cable (?), and there are indeed two of them, joined together in a figure of 8 way.

    Searching for this, another site suggests that the strands are "0.19mm", would this be the diameter? Or the radius? I'm guessing diameter, but you all know what assumptions are like.

    This same site also states that the wire is 1.32mm^2 and I am assuming that this is for each 42 strands-in-total wire, not for both the wires.

    So are modern multi-strand wires all made from 0.19 mm strands, bundled to whatever size is necessary for the wire?

    I am not sure of the correct nomenclature with regards to the individual strands, the greater wire within the insulation, and the name for the wire made from two (or more, I suppose) insulated wires joined together (cables?), so please feel free to ridicule my ignorance.

    Thanks in advance.

    This is speaker wire, for low voltage usage, so just don't ever
    use it for mains voltage. It is multi-stranded primarily for
    flexibility (likely to vibrate under the influence of the
    speaker), and HiFi 'purists' might say there is a electronic
    reason for using multi-stranding instead of solid core (or maybe
    the opposite, I wouldn't know).

    The Skin Effect applies at any frequency, to one extent or
    another. Using a multitude of tiny strands, is an attempt
    to conduct the AC frequencies better (for a given total cross-section
    of cable).

    https://en.wikipedia.org/wiki/Skin_effect

    When you take Power Systems, they make you work out
    the skin depth at power line frequencies. There is
    still an effect at 50Hz.

    From a Google:

    "at 50 Hz or 60 Hz the skin depth in copper is around 9 mm (Fig. 1a, b).
    This is partly the reason for the high-current busbars in low-voltage
    switchgear to be made with copper bars not thicker than 10 mm
    "

    Paul

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  • From The Natural Philosopher@tnp@invalid.invalid to uk.d-i-y on Mon Feb 23 14:34:27 2026
    From Newsgroup: uk.d-i-y

    On 23/02/2026 14:15, Paul wrote:
    On Sun, 2/22/2026 2:20 PM, Andrew wrote:
    On 22/02/2026 18:22, David Paste wrote:
    I know nowt.

    I have a roll of "2x42 speaker cable" which indeed has 42 strands of very thin copper wire in each cable (?), and there are indeed two of them, joined together in a figure of 8 way.

    Searching for this, another site suggests that the strands are "0.19mm", would this be the diameter? Or the radius? I'm guessing diameter, but you all know what assumptions are like.

    This same site also states that the wire is 1.32mm^2 and I am assuming that this is for each 42 strands-in-total wire, not for both the wires.

    So are modern multi-strand wires all made from 0.19 mm strands, bundled to whatever size is necessary for the wire?

    I am not sure of the correct nomenclature with regards to the individual strands, the greater wire within the insulation, and the name for the wire made from two (or more, I suppose) insulated wires joined together (cables?), so please feel free to ridicule my ignorance.

    Thanks in advance.

    This is speaker wire, for low voltage usage, so just don't ever
    use it for mains voltage. It is multi-stranded primarily for
    flexibility (likely to vibrate under the influence of the
    speaker), and HiFi 'purists' might say there is a electronic
    reason for using multi-stranding instead of solid core (or maybe
    the opposite, I wouldn't know).

    The Skin Effect applies at any frequency, to one extent or
    another. Using a multitude of tiny strands, is an attempt
    to conduct the AC frequencies better (for a given total cross-section
    of cable).

    https://en.wikipedia.org/wiki/Skin_effect

    When you take Power Systems, they make you work out
    the skin depth at power line frequencies. There is
    still an effect at 50Hz.

    From a Google:

    "at 50 Hz or 60 Hz the skin depth in copper is around 9 mm (Fig. 1a, b).
    This is partly the reason for the high-current busbars in low-voltage
    switchgear to be made with copper bars not thicker than 10 mm
    "

    Paul

    However, for stranded wire at audio frequencies its pretty much
    something you canb ignore...
    --
    rCLIt is hard to imagine a more stupid decision or more dangerous way of making decisions than by putting those decisions in the hands of people
    who pay no price for being wrong.rCY

    Thomas Sowell

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  • From Simon Simple@nothanks@nottoday.co.uk to uk.d-i-y on Mon Feb 23 16:20:19 2026
    From Newsgroup: uk.d-i-y

    On 23/02/2026 14:15, Paul wrote:

    <xxx>

    The Skin Effect applies at any frequency, to one extent or
    another. Using a multitude of tiny strands, is an attempt
    to conduct the AC frequencies better (for a given total cross-section
    of cable).

    https://en.wikipedia.org/wiki/Skin_effect

    Multiple strands in speaker wire are for flexibility. If skin effect is
    an issue you'd use eg Litz wire where each tiny strand is insulated. A
    bugger to solder though. A molten NaOH bath is a good way to strip it.

    https://en.wikipedia.org/wiki/Litz_wire
    --
    SS

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  • From Simon Simple@nothanks@nottoday.co.uk to uk.d-i-y on Mon Feb 23 16:20:31 2026
    From Newsgroup: uk.d-i-y

    On 23/02/2026 14:15, Paul wrote:

    <xxx>

    The Skin Effect applies at any frequency, to one extent or
    another. Using a multitude of tiny strands, is an attempt
    to conduct the AC frequencies better (for a given total cross-section
    of cable).

    https://en.wikipedia.org/wiki/Skin_effect

    Multiple strands in speaker wire are for flexibility. If skin effect is
    an issue you'd use eg Litz wire where each tiny strand is insulated. A
    bugger to solder though. A molten NaOH bath is a good way to strip it.

    https://en.wikipedia.org/wiki/Litz_wire
    --
    SS

    --- Synchronet 3.21b-Linux NewsLink 1.2
  • From The Natural Philosopher@tnp@invalid.invalid to uk.d-i-y on Mon Feb 23 18:23:18 2026
    From Newsgroup: uk.d-i-y

    On 23/02/2026 16:20, Simon Simple wrote:
    On 23/02/2026 14:15, Paul wrote:

    <xxx>

    The Skin Effect applies at any frequency, to one extent or
    another. Using a multitude of tiny strands, is an attempt
    to conduct the AC frequencies better (for a given total cross-section
    of cable).

    -a-a-a https://en.wikipedia.org/wiki/Skin_effect

    Multiple strands in speaker wire are for flexibility.-a If skin effect is
    an issue you'd use eg Litz wire where each tiny strand is insulated.

    Not necessarily. There is no doubt that stranded non Litz wire is better
    than solid core for longish runs of e.g. audio and indeed HV grid cables.

    How *much* better is the issue.

    In general for signal applications the whole cable impedance is very low relative to the end point impedances.

    Which is why e.g. CAT 5 house wiring is solid core.

    About the only domestic application - and its marginal - where
    stranded makes a difference in signal levels is audio speaker cables.


    A
    bugger to solder though.-a A molten NaOH bath is a good way to strip it.

    https://en.wikipedia.org/wiki/Litz_wire


    Haven't seen it in years. They uses to use it for the long wave part of ferrite road aerials in portable radios. And in some valve sets

    In general a transistor to add gain is a lot cheaper than a litz wire
    coil. :-)
    --
    "A point of view can be a dangerous luxury when substituted for insight
    and understanding".

    Marshall McLuhan


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  • From Chris Green@cl@isbd.net to uk.d-i-y on Mon Feb 23 20:06:47 2026
    From Newsgroup: uk.d-i-y

    The Natural Philosopher <tnp@invalid.invalid> wrote:
    On 23/02/2026 16:20, Simon Simple wrote:
    On 23/02/2026 14:15, Paul wrote:

    <xxx>

    The Skin Effect applies at any frequency, to one extent or
    another. Using a multitude of tiny strands, is an attempt
    to conduct the AC frequencies better (for a given total cross-section
    of cable).

    -a-a-a https://en.wikipedia.org/wiki/Skin_effect

    Multiple strands in speaker wire are for flexibility.-a If skin effect is an issue you'd use eg Litz wire where each tiny strand is insulated.

    Not necessarily. There is no doubt that stranded non Litz wire is better than solid core for longish runs of e.g. audio and indeed HV grid cables.

    How *much* better is the issue.

    In general for signal applications the whole cable impedance is very low relative to the end point impedances.

    Which is why e.g. CAT 5 house wiring is solid core.

    About the only domestic application - and its marginal - where
    stranded makes a difference in signal levels is audio speaker cables.


    A
    bugger to solder though.-a A molten NaOH bath is a good way to strip it.

    https://en.wikipedia.org/wiki/Litz_wire


    Haven't seen it in years. They uses to use it for the long wave part of ferrite road aerials in portable radios. And in some valve sets

    In general a transistor to add gain is a lot cheaper than a litz wire
    coil. :-)

    But if there isn't enough signal to start with just amplifying what
    you have isn't going to help. An extra few dB of 'real' signal might
    make all the difference.
    --
    Chris Green
    -+
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  • From David Paste@pastedavid@gmail.com to uk.d-i-y on Thu Feb 26 13:35:46 2026
    From Newsgroup: uk.d-i-y

    On 22/02/2026 18:46, Theo wrote:

    Usually stranded wires are written as 7/0.1 which means 7 strands of 0.1mm diameter wire. You can get many different combinations of diameter and number of strands. Then of course you get multicore cable which might have
    9 cores each being of 7/0.1mm.
    Cheers!
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  • From David Paste@pastedavid@gmail.com to uk.d-i-y on Thu Feb 26 13:45:48 2026
    From Newsgroup: uk.d-i-y

    On 22/02/2026 19:20, Andrew wrote:

    This is speaker wire, for low voltage usage, so just don't ever
    use it for mains voltage. It is multi-stranded primarily for
    flexibility (likely to vibrate under the influence of the
    speaker), and HiFi 'purists' might say there is a electronic
    reason for using multi-stranding instead of solid core (or maybe
    the opposite, I wouldn't know).

    Oh yeah, I am not daft enough to use it for mains leccy!

    I was just curious abou the nomenclature and measurements, etc.

    As for Hi-Fi folk, it has been revealed to me in a series of copper
    scroll found buried in the woods that most of the "purists" have quite obviously not bothered to take even the most rudimentary measures of
    their own hearing using a tone generator and headphones (or their
    stereo), and had a go at using low- and high-pass filters on digital
    copies of their music, both tasks can be done with the free software "Audacity". The copper scrolls have stated that these people probably
    listen to the difference of reproduction of their venerated Hi-Fi
    equipment of choice rather than the music itself. Each to their own of
    course.
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  • From David Paste@pastedavid@gmail.com to uk.d-i-y on Thu Feb 26 13:48:13 2026
    From Newsgroup: uk.d-i-y

    On 22/02/2026 20:30, The Natural Philosopher wrote:

    Technically it was known as doorbell wire.

    Definitely OK up to midfi levels for audio. Bigger stranded silicone
    cable is made for serious power levels and best bass damping or for any
    high current wiring needing low resistance and good mechanical flexibility

    What power levels are you talking about when you say "serious"?

    Is the silicon insulation important, or is that just a desirable thing
    for flexibility or something? Surely the copper will be the overarching flexibility factor?


    I have used it for light pendants and (slaps wrist) mains table lamps as well

    Even I wouldn't do that, and I know nowt.

    Cheers.
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