At 01:23 PM 2008-11-17, Philip Tyler wrote:
>Cable wise check out this:
>
>http://www.canford.co.uk/Products/30-436.aspx
>
>A lot cheaper than Mogami and a little cheaper than Canare. But this
>cable is made to the BBC spec and the BBC uses miles of the stuff
>and I have never heard of anyone having a problem with it. I found
>it excellent stuff to work with and use it for all my stuff.
That looks like a great implementation of "Star Quad" which as Neil
Muncy has shown will often lower external hum pickup from the cable
by perhaps 20 dB. Despite its four conductors, it is considered a
mono cable in my experience. The two opposing wires are used in
parallel which is how it improves hum rejection. The high number of
twists per inch also helps.
However, co-twisted cables like this have poor high-frequency
crosstalk. Now, I don't know how poor it will be compared to a stereo
mic's separation, but it is something we should be aware of -- the
capacitive coupling between the two stereo signals is very high in
this construction.
The 8723 https://edeskv2.belden.com/Products/#s=8723&r=0 that I have
in semi-bulk that I might use for this project is similarly laid
down, but it has a figure-8 shield separating two pairs. It is
common-twist, but the shield isolates the two channels. It has to be
this way to be round. Two separate twisted pairs ends up an oval cable.
Cheers,
Richard
Richard L. Hess
Aurora, Ontario, Canada http://www.richardhess.com/
Detailed contact information: http://www.richardhess.com/tape/contact.htm
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