ferrite for interconnect...

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Hi friends

I was tempted to build this interconnect: DIY Silver RCA Interconnect Cables

fun and simple to build. It seemed.
But when I started to source the parts, I found that I couldn't just blindly "get parts". The required ferrite-core does not tell much, my source lets me select specific impedances @ frequencies...
So I tried to find out about those details, but found nothing.
Gosh, where could I learn about it!
david
 
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... what frequencies are to be attenuated...

... or use shielded cable.

Indiglo, thank you for the direction.
You got to my weak point—what frequencies to attenuate. What are the parameters? Does it depend on the environment (how quiet it is) or on the gear (what devices get connected)?
I vaguely remember something about hf interfering with the signal, but there must be more, but what?

And yes of course, shielded cable. I wanted to see (well, hear) what it was about those claims about the shield (some inductance or something) interfering with the signal.
I’m pretty sure I won’t hear any difference, but as long as I haven’t heard it I don’t know.
 
It's good that you ask these questions, typically cable clamp-on ferrites are used to attenuate RF energy for either ingress or egress type arrangements, as an example you may see round cylindrical mouldings on consumer products like these to reduce EMI radiating from the cable.

An another example which would be more appropriate if you had a radio amateur with a high powered HF radio transmitter living close by and when transmitting may induce RF energy into your audio inputs via the interconnect cables. Fitting a ferrite clamp to the cable will reduce the amount of RF energy entering the audio device by converting it to heat.

I suggest if you are not experiencing any type of radio interference in your audio devices all you really need to use is good quality shielded cable. No need to spend large sums of money, do a search for Belden shielded audio cable.

Capacitance and inductance in cables is mostly negligible for most devices except for connecting a phono turntable to a preamplifier where you want low capacitance cable.
 
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The op didn't state they had interference, there's absolutely no need for coax unless you live next door to a 10kw radio transmitter and then the ingress of RF is probably via another mechanism in any case.

Belden shielded audio cable is all is required anything else is a extravagant waste of money.
 
The op didn't state they had interference, there's absolutely no need for coax unless you live next door to a 10kw radio transmitter and then the ingress of RF is probably via another mechanism in any case.
Belden shielded audio cable is all is required anything else is a extravagant waste of money.
Jim Brown an AES EMI/RFI expert thinks that there are about 30 RFI sources in a typical modern home.
All RCA interconnects should use a coax cable.
 
Mostly what Jim discusses relates mostly to AM broadcast and Ham HF radio transmitter RFI into microphones at close range, its unlikely the average suburban home will see any RF signal levels of that magnitude.

My advice to the op is to avoid the audiophile fad of silver cables and just use some decent shielded cable and connectors.
 
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Thanks for all these inputs.
I understand both the pro and contra (not technically, but "conceptually")...
When I was thinking about making those cables, it was about finding out wether the use of shielded cable has an audible influence... (of course, the silver conductor is tempting too... :roll eyes:

BTW, I already went very low and used twisted 0.3mm enameled copper wire, no shields, and ugly, cheap rca-plugs. It worked and was fun, but I didn't went very far into it...
 
Hi friends

I was tempted to build this interconnect: DIY Silver RCA Interconnect Cables

Ummm... no. Always, always, always use shielded "microphone" cable for RCA interconnects. Well, unless you want your system channelling the local CBer... "Breaker Breaker Any Taker"...

The snap on ferrite beads won't hurt your audio response at all. Most have no effect under about 2 mhz. But when deployed at your amp inputs they can help keep that pesky CBer out... When I make interconnects, I put them on as a matter of course. They're cheap and they're not going to make anything worse, so why not.

Recent phone call: "Why is my stereo humming?" ...
Me: "Because it doesn't know the words."
 
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Randomly suggesting ferrites is not the appropriate method.

You need to determine what frequency range, how much attenuation you require, how many loops of cable need to pass through the ferrite, what is the appropriate ferrite material, what core size or cable diameter is needed.

If you use shielded cable and not experiencing any RF EMI then you don't need ferrites.

Ferrite 77 is mainly used as a toroid in switchmode power supplies.
 
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Randomly suggesting ferrites is not the appropriate method.

You need to determine what frequency range, how much attenuation you require, how many loops of cable need to pass through the ferrite, what is the appropriate ferrite material, what core size or cable diameter is needed.

I totally understand that this should be a „targeted approach“

No way am I able to achieve this.

So I‘ll go the killall-way and use shielded wire [emoji41]
 
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If you want the expensive audiophile look you can always fit some fancy cable sleeving over the top and nobody will know the difference :)

Cable Sleeving


I could use a vacuum-tube for sleeving to get a reeaallly hefty look. [emoji851]

(Actually, I prefer stuff like that: Google-Ergebnis für https://i.ebayimg.com/images/g/pygAAOSwol5Y0ecD/s-l400.jpg )
IMG_2021.jpg
 
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