Jez,
When I was first shown how to make up my own leads (by the legendary
Ed Slater) he recommended using Canare cables which are beautifully
flexible even in cold conditions, and that the advantage of using
quad cable for stereo recording was that you had back up with 2 cores
going to each channel, instead of just one. Also you would have
better external noise rejection because the wires were spiralled
together rather than laying flat. All the Canare cables seem to use
aluminium shielding.
The lightest Canare cable I can find is 4E5C and very nice cable it
is too.
Even lighter is Belden mini-star quad 1804A, which has aluminium
shielding and is very flexible, suitable for super lightweight rigs,
but rather fiddly to solder. I use two strands of it with two XLR
mics for stereo recording (a 6-meter length), and the two strands are
held together every half metre with a small piece of shrink tubing.
Regarding 4-quad cable, the Belden website says this:
<How Quad Microphone Cables Works
Combining pairs in a spiral configuration affects what is called the
"loop area". That means, the closer the wires stay together, the more
likely that the noise and interference they encounter will be the
same on each wire and the more likely the noise can be canceled by
being a balanced line. Quad cable has the added advantage of having
pairs of wires. They provide noise cancellation ("common mode
rejection") at each pin, as well, due to the connection as a balanced
line.>
Another cable that I have used for electret mics is Tasker figure 8
cable 'shielded twin cable C118'. This uses copper strands for the
shield, and also for the core. It has 2 cores, 1 for each channel.
Made in Italy, impossible to obtain in Australia, beautifully
flexible (unlike most other fig 8 cables that I've seen). I can't
see why it wouldn't work for XLR connections too. For long cables in
noisy environments perhaps it would be more likely to pick up noise,
than the Canare and Belden type of cables?
I am absolutely NO expert on cables, but just mention my own personal
experiences.
I was also told never to wind the cable onto a barrel (strains the
cable), but to hand-loop the cable in a way that it would not kink.
Vicki Powys
Australia
On 22/06/2012, at 12:43 AM, Jez wrote:
> thanks - some confusion here. I am talking about mid to higher end
> balanced microphone cable, such as some made by Klotz, Van Damme
> etc & it states, for example:
>
> 2 core, balanced pro microphone cable, aluminium braided shield and
> stranded copper cores.
>
> I'm also slightly confused by the comment about the number of wires
> inside the shielding - 2 cores is balanced audio cable, 4 is quad
> etc, but 2 wires (2 cores) is standard for balanced audio.
>
> --- In Magnus Bergsson
> <> wrote:
>>
>> @Jez. The reason is just that Aliminium is very good material to
>> screen off
>> all electrical noise pollution in surroundings. If the cable do
>> not have
>> any parallel copper wire with the shield I would think the cable
>> is made
>> for something else than audio.
>> It also depends of how many wires are inside the aluminum shield.
>> If they are just two I would not use it for balanced audio. If
>> they are
>> three or four they must be twisted. Then I think the aluminium shield
>> should be connected to equipment outer case. For this reason John
>> is right
>> when he say cable with aluminium shield are specially made for fixed
>> installations.
>>
>> Magnus
>>
>>
>>
>> On Thu, Jun 21, 2012 at 8:17 AM, Jez <> wrote:
>>
>>> **
>>>
>>>
>>> thanks Magnus. When you say its not good for audio signals it
>>> makes me ask
>>> even more why some very high cost cable manufacturers use an
>>> aluminium
>>> shield !
>>>
>>>
>>> --- In Magnus Bergsson
>>> <fieldrecording.net@> wrote:
>>>>
>>>> I just know that aluminium is the best material to shield
>>>> electrical
>>> noise
>>>> pollution. It is not only the price of the material why it is so
>>>> widely
>>>> used. That is one of the reason why aluminium is common use for
>>>> shielding
>>>> in UHF transmitting and receiving technology.
>>>> Aluminium is not good for audio signal, so parallel with the
>>>> aluminium
>>> foil
>>>> should be a copper wire.
>>>>
>>>> By the way...
>>>> I have make a cheap 50 meter stereo snake with Cat6 cable.
>>>>
>>>>
>>> https://picasaweb.google.com/104187345157190691446/
>>> Stereo50mCAT6Snake?authuser=3D0&feat=3Ddirectlink
>>>>
>>>> I have not notice any electrical noise pollution with this
>>>> snake, even
>>>> though it has no shield. Probably because it is mostly used
>>>> outdoor.
>>>> Differently twisted pair is also very good technique to shield high
>>>> frequency.
>>>> But anyway, I always try to delete or minimize all source of
>>>> electrical
>>>> pollutions before it makes a problem to other equipment or
>>>> humans :-)
>>>>
>>>> --
>>>> Bestu kve=F0jur / Best regards
>>>> *Magn=FAs Bergsson
>>>> *Tel: + 354 6162904*
>>>> *
>>>> http://fieldrecording.net
>>>
>>>
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