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[SOLVED] Ultra low shunt capacitance cable needed

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neazoi

neazoi

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hello I need to find a xoacial cable type with as low shunt capacitance as possible.
Interested only in audio frequencies.
I would like it to have silver plated conductors like RG223.

RG223 has 100pf/m shunt. is there any better alternative at this cable diameter?
 

is there any better alternative? he lowest shunt the better
 

What you need (or are minimum some better) is: RG180B/RG178A or RG19B (diameters 2.5...3.6mm) :)...
https://www.dpcav.com/data_sheets/rg174.pdf
K.

Added after 1 minutes:

But I dont understand your capacitance problems at audio freq`s...
 

    neazoi

    neazoi

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It is the sound quality that is affected by shunt capacitance.
anyway, do you know what is the maximum power it could handle? my audio amplifier is 8W

Thank you
 

No,
I dont no, but check datasheet/table pls.
Voltage is surly not a problem, usual over 3-400V, as you knows it too, but the middle wire has a diameter of 60-160 micron only...
But tell me pls; why is on a audio pwr output asome cable capacitance a problem?
K.

You can chek the homesides from Belden & Alpha Wires, both hase lot of professional cables in program...
 

Fot lowest capacitance, you may want to use a 150 ohm coaxial cable. But it's surely not suited for power applications because the it has very thin inner conductor, as karesz noticed.

For speaker cables, the sound quality is mainly affected by unwanted cable inductance rather than capacitance. The lowest inductance is either achieved with special coaxial cables or braided multi-conductor cables. The capacitance will be many 100 pF/m as a side effect.
 

I have read an article speaking about the "sound of cables" somewhere which states the issue of shunt capacitance.
I really do not know what to do. I have a direct coupled class-A 8W amplifier and I would like the best DIY that can be done.

I am thinking of using the RG223 coaxial which is somehow cheap and silver plated. Then I could even use it as coaxial or I could rip out the shield and use only the internal conductor (and insulation) to form a two wire speaker cable, either twisted or untwisted.

Any ideas?
 

Hey,
you can twist simple two coaxes where are in both the inner conductor & hes shilding shorted :)
But in that case is the, even silver plated, RG174/U(or other thinner types) maybe better...
K.
 

After your useful advices I have decided to make the speaked cables like this shown in the photo.
They are composed of a pair of RG223 central conductors with thei insulations, twisted together. This ensures minimum dielectric contact and at the same time noise won't affect the cable..?

Is the way I have done it right?


Also, can I use the same configuration for interconnections? Will this impose a gain in relation to the coaxial?
 

Yea,
You can try it_only, I (personaly) can not believe that it brings some better Hi-Fi parameter for you! Thats life!
Only silver surface is logically OK, but all the stuff over smaller noise receiveing? Where, in a power output!?
No ne, UFF!
In Audio magazines are so much writen in the past 30-40 years, what if you will give for a dog to eat: it will dead,
but with high or light-speed...
K.
 

Thank you,
I am looking for a way to minimize shunt capacitance, I have read some articles talking about it and some companies do steps in trying to achieve the "perfect" cable solution...
I have also discussed with some audiophiles and they proposed me the twisted technique which works like twisted pair cabling in UTP computer networks.
To be honest I do not understand how noise can be cancelated in a system that is no using comparator opamps but...if they say so..
 

FvM said:
For speaker cables, the sound quality is mainly affected by unwanted cable inductance rather than capacitance.
Click to expand...

Exactly. Cable capacitance matters only for high impedance source/load.

If you choose a coax cable with minimum capacitance, this means a smaller inner diameter -> more loss. That is a (negative) effect which will make a difference at audio frequencies.
 

Seriously, I'm not motivated to comment some esoteric thoughts about "sound of cables" because it makes no sense to contradict religious beliefs.
 

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