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Old 27th April 2011, 01:44 PM   #11
qusp is offline qusp  Australia
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Quote:
Originally Posted by stratus46 View Post
Why would you think 50 ohm cable is better for running 'non-terminated'? I would think you'd be interested in the amount of capacitance per foot as that is going to form a low pass filter combined with your output resistance. Looking at Belden 8219 50 ohm coax has 25.5 pF /ft vs 1505F 75 ohm coax at 17.5 pF/ft. It's not a massive difference but it is opposite what I'd expect you to be concerned about.

RG-405 comes up 'No products found matching criteria.'.

G
where did i say that? i only asked if he had a mechanism, or was already terminating it. if you actually read my post instead of picking parts to argue with i mentioned that this was probably not as important with his application and that 75r coax (for digital) was primarily designed for external digital interconnects and internal digital was primarily 50r, all of this wrt digital. termination and impedance is just as important for analogue interconnects, you need only look at the work of Erno Borbely to see examples of it. i fully agree that the pricing of the 100 a meter is a bit over the top and did not recommend it, my use of silver in these situations with coax of my own making is a matter of consistency and because i can and have found good results; i'm not going to get into that with you.

in fact i clearly stated that someone was probably going to come in here and say that he should be using 75r coax for audio, even though we were talking analogue.

wrt not getting any hits; you are not looking hard enough
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Old 27th April 2011, 03:16 PM   #12
AndrewT is offline AndrewT  Scotland
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If you have strong intuition that screened (coaxial) offers some significant advantage over twisted pair, then use screened two or screened four core (star quad) microphone cable.
Single core coaxial is a waste of time in my non-expert opinion for all audio frequency uses.
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Old 27th April 2011, 04:12 PM   #13
qusp is offline qusp  Australia
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i'm only using it for power and sense, digital or 2 x mini coax also twisted sometimes for low level signal. that vhaudio copper one is pretty thin and allows this. but erno and a number of people on here seem to dig it for low level analogue. i have tried it all over, but i usually cant be assed to do it all the way through due to extra effort in grounding and end up with twisted pair, sometimes shielded if im in the mood for overkill or having a neat fit

all part of my audiopsychosis

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Old 27th April 2011, 04:42 PM   #14
flg is offline flg  United States
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This thread is no doubt on it's way to a "do cables make a difference", or whatever, pile of chit chat crap, type of "discussion". Is that what we want to be reading here? Is this what you guy's that "know" want to be posting here?
BTW, I use the tan colored, .1", teflon insulated, 18pF/", 50ohm coax for small signal SE stuff.
otherwise, I twist
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Old 27th April 2011, 04:52 PM   #15
qusp is offline qusp  Australia
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i only 'know' what works for me, but i agree its really not the sort of thread that needs to be in this section and was a touch confused at the first post. just happens i bought a fair few different types recently for a measurement amp i built, so i chimed in and then someone took my comments out of context so i tried to explain myself when i probably should have just ignored it.

tan?? really?, dont you find that muddies the sound? i prefer clear teflon or black for that black background
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Old 27th April 2011, 05:52 PM   #16
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Quote:
Originally Posted by qusp View Post
.

tan?? really?, dont you find that muddies the sound? i prefer clear teflon or black for that black background
Awww, qusp..... you beat me to it....! (Actually, I prefer the red--I think it makes the electrons go thru it faster.....)
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Old 28th April 2011, 03:34 PM   #17
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And you should regularly pass some DC current through them to replace the old electrons (maybe that's what memory distortion really is?)

I use RG316/U, mainly because I have a 50m ring of it...
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Old 28th April 2011, 04:26 PM   #18
qusp is offline qusp  Australia
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Originally Posted by CanAm Man View Post
Awww, qusp..... you beat me to it....! (Actually, I prefer the red--I think it makes the electrons go thru it faster.....)
what can i say it was begging for it

one problem i find with all this coax no matter the price, is that because ground and signal are inseparable, it makes it difficult, or at least problematic to have the ground lines running down hill without effecting electron flow through the signal lines....this is very important for small signals.

ok, i'm passing the thread over, anyone else wanna have a go before the mods move it?

Last edited by qusp; 28th April 2011 at 04:29 PM.
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Old 28th April 2011, 05:28 PM   #19
Itsmee is offline Itsmee  England
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Quote:
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tan?? really?, dont you find that muddies the sound? i prefer clear teflon or black for that black background
Don't use clear teflon, the photons bump into the electrons
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Old 28th April 2011, 05:38 PM   #20
flg is offline flg  United States
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This "Tan" stuff I use has white Teflon dielectric between the center and shield. I am down to my last few meters though...
What does Papa use?
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