Cable capacitance. How low can YOU go?

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#1
I can't get any lower than 36 pF/m using diamond-braided 49-strand/8-core non-shielded SPC.
I tried different braid patterns, nore and less cores as well as combinations of SPC/copper but 36.18pF/m is currently the limit.
Anyone made or seen anything that goes lower?
It's become an obsession now, lol.

Full SPC
DSC_0660_1.JPG

SPC/copper
IMG_20240119_200157.jpg


Measured a 1m length of 55pF/m vanDamme Silver Series LoCap55 at 57pF/m, so I know there's potentially a 2pF/m gain to re-claim...if vanDamme are being truthful and if my LCR meter is measuring slightly over.
That 2pF/m potential gain is important to me...or rather my OCD.
Need....to get....under...35pF/m Scotty!
She cannae take any morrrre Captain!!

DSC_0677 Copy_1.JPG
 

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#3
I litz braided CAT6 wire (de-stranded) for a tonearm once but never measured it...

Five strands (2l, 2r and ground)
CAT6 is a very underrated cable type for audio imo, especially in twisted-pair and shielded format. Cheap as chips and has an incredibly dark noisefloor. I use it for analogue signal connections for digital source components, SACD players with good on-board DACs etc.
 

wattsabundant

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#4
I learned the hard way of the value of cat 5 cable. When I did my home network in the late 90's I mistakenly used one wire from one pair and one wire from a different pair. The network cards' LED lit up ok. The network crashed and crashed. My friend stopped by and looked at the install and said "Don, you're an idiot" I correctly relanded the wires and it still works great, 30 years later.
 

Gepetto

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#5
I learned the hard way of the value of cat 5 cable. When I did my home network in the late 90's I mistakenly used one wire from one pair and one wire from a different pair. The network cards' LED lit up ok. The network crashed and crashed. My friend stopped by and looked at the install and said "Don, you're an idiot" I correctly relanded the wires and it still works great, 30 years later.
You learned the value of a pair Don... (here comes Navo)
 

MarkWComer

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#6
I litz braided CAT6 wire (de-stranded) for a tonearm once but never measured it...

Five strands (2l, 2r and ground)
Never thought of using ethernet cable for tonearm wire…
I used to get tonearm wire sets from “Garage-A-Records” for record changers and old school record players. I think they’re out of business now.

Edit: They’ve been assimilated by turntableneedles.com.
 

J!m

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#7
It’s not very flexible but a loop or two helps at the gimbal.

I never finished that arm but the litz braid fit the carbon tube snugly enough to provide acoustic damping of the tube.

But I conceived a better arm tube design which changes everything else and never built it.

It’s a novel construction I’ve never seen that is light, stiff and devoid of a single resonant frequency- it would either have several, or none, but no peaking. The carbon tube rings like a steel tube and frequency is controlled by length. Hence the damping. That energy transfers to the wire and could be audible…
 

Northwinds

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#8
I read somewhere a guy made a straight tonearm out of a Dunkin Donuts straw. No damping needed. Idk what he used for a locking collar for the headshell though. This was a few years ago
 

mlucitt

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#10
I can't get any lower than 36 pF/m using diamond-braided 49-strand/8-core non-shielded SPC.
I tried different braid patterns, nore and less cores as well as combinations of SPC/copper but 36.18pF/m is currently the limit.
Anyone made or seen anything that goes lower?
It's become an obsession now, lol.
Full SPC
I believe the low pF/m reading for the diamond-braid cable is because there is no shielding. I would not want to run an interconnect without shielding.
 
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#11
I believe the low pF/m reading for the diamond-braid cable is because there is no shielding. I would not want to run an interconnect without shielding.
Shielding can be implemented very effectively in different ways.
The braided geometry of the cable forms an EMI/RFI shield via CMRR, hence braided/twisted cables without a traditional shield 'layer' are still very effective at shielding noise.
CMRR forms the basis of many of my other cable designs and is highly effective (and measurable) at mitigating external noise/interference.
I got laughed at and eventually banned from ASR for asserting that claim. Strange, seeing as how CMRR implemented in cables is well-established, documented and implemented by others.
I offered up 2 of my cable types to Amir for testing and he repeatedly declined. I suspect due to knowing exactly what the outcome would be and wanting to save face in front of his baying disciples. Lame.

Some examples
05_1.jpg
07_1.JPG


'Twisted pair' geometry is well-established as an effective shield method and if you have ever stripped a network cable down, even those from 30 years ago you'll observe twisted pairs of conductors. Again, this is to facilitate shielding via CMRR. So, now there is a 'twisted-pair' geometry implemented into some of my designs. Some of the cable-types use already have internal twisted pair conductor topology and traditional shielding layers so there are effectively double and triple shielding present.

'World of Twist'

13.jpg
11.JPG
06.jpg
10.JPG
 
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#13
Here is a good article from Benchmark regarding cable geometry and its benefits:

Star-Quad Cable
That's a good, clear write-up / explanation.
Obviously using it for marketing purposes but then *kof* who doesn't?
If only those measurement-obsessed turd-suckers over at ASR accepted it everything would be right with the world. But then, who gives a sh!t about them?
:D
 

mlucitt

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#14
Twisted pair geometry is ideal to reduce typical magnetic interference from 60 Hz AC motors and fluorescent lighting, etc. through CMRR. However, my HAM radio operating at 500 Watts at 12.350 KHz RF will punch right through any cable that is not 100% shielded.
And yes, I have some Cat 6A twisted pair network cables as interconnects and low power bookshelf speaker cables and all of it is foil shielded.

I was simply pointing out that in a shielded cable some of the capacitance is formed between the conductors and the shield. If your cables do not have traditional shielding, I would expect less capacitance.
 
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