From: "Rich Peet" <>
>
>>> I would suggest you go and read the link I gave earlier, it's
>
> written by
>
>>> a engineer who does not work for Canare, but just sells all types of
>>> cable. You will find there are advantages in the star quad design
>
> beyond
>
>>> the noise resistance. Particularly in high frequency loss on long runs.
>>> http://www.procosound.com/whitepapers.htm
>>>
>
>
> ok, I'll bite. I will try the two wire version. Do you want to bet
> if it really has a 20 db noise reduction under a 1kw dimmer controlled
> lite fixture compared to the same thickness star quad?
You sure you don't want to take that sentence in for a refit. As it
stands you are testing if two wire twisted pair mic cable has 20 db less
noise than star quad. You sure that's what you want?
Yes, since Canare makes both twisted pair and star quad with the other
parameters the same, a test can be done. As oscillograms by Canare and
others have shown. Generally the reference is to the high power SCR
controlled TV studio lighting. Actually, to the cable feeds, not the
lights themselves. For TV studios that appears to be their worst source.
Assuming you are referring to the same light, you can toss your
oscillograms in the big pile that others have already contributed. I've
seen many of these on the internet over the years. And, yes, they don't
all come out exactly 20db. But every one I've seen the star quad is
reducing the noise more.
Note carefully, if your intent is to prove that Canare put out a
misleading statement, that link I gave is not to a paper by Canare, but
the engineering department of a cable seller, a entirely different
company. 20 db is their statement. I noted it was a different group when
I first put the link up. Canare on their "star quad story" page does not
state a value, though you can read the value difference off the two
oscillogram pictures. One could say they are being misleading between
the two places as the oscillogram shows a different difference than 20
db. It shows a slightly greater value.
I'm also just a little curious. Suppose it comes out that the value you
get is 19 db. Will you then reject the cable? If not at what value of
sound improvement would you reject the cable?
And after that is the better high frequency transmission of star quad on
longer runs also unimportant?
>>> Actually I do find the capabilities in a magnetic field useful in
>
> nature
>
>>> recording. Before going to star quad I used to have occasional problems
>>> in the fields under power lines. Not just the high tension lines, who's
>>> right of way is often prime frog country, but even under the 15 kV
>
> rural
>
>>> power distribution lines. It's amazing how far away from such lines you
>>> can still pick up hum with lessor designs of cable. Even with star quad
>>> I've run into places under high tension lines that the fields were so
>>> strong as to get into the recorder, or into the mic. And in moist
>>> weather, even without getting in, the crackle of the electrical
>>> discharge from them will be recorded.
>
>
> I avoid power lines, you avoid jets. I got it easier than you.
You don't record for scientific survey documentation. I have to record
wherever the frogs are. Especially in the case of the large power lines,
the cleared zone and constant AWD maintenence traffic insures lots of
the small water that so many frogs like. And down here frequently those
lines are darned close overhead.
The jet traffic down here is much more dense than you deal with. I
cannot avoid it. I live with it as best I can. Yes, you have it easier.
In the case of cable, I'm quite sure there are plenty of times I have no
need at all of the shielding. But, I build my cables for the worst case,
not the best case. That way I don't have to change cables when I hit the
worst case. One set of cables covers it all.
Walt
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