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5. Re: cable question

Subject: 5. Re: cable question
From: "Richard L. Hess" richardlhess
Date: Mon Nov 17, 2008 10:47 am ((PST))
At 01:23 PM 2008-11-17, Philip Tyler wrote:

>Cable wise check out this:
>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 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.



Richard L. Hess                   
Aurora, Ontario, Canada
Detailed contact information:  

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