RF Interference in Speaker Cables??? (video)

[tomchr]

Mine are GLS brand 12 AWG with Neutrik speakON connectors. No fancy cable geometries here. Just a plain pro audio cable. Cuz the electrons don't seem to care.

Tom

 

[respice finem]

...I have found that RF interference and ground loops are more of an equipment problem vs cable.

And those can't be solved by changing the cable, speaker cables anyway.

 

[milosz]

RFI problems in audio gear CAN BE VERY REAL. Not in the way "audiophiles" represent, but in a strong enough RF field the RF signal can couple into gain stages in various ways and the frequency being way higher than audio electronics are designed to cope with, the gain devices can be pushed past their linear operating parameters. At the least this causes a characteristic "buzz" in the audio - which is CLEARLY audible - and at worst can blow up an amplifier. I was testing a 2 meter (approx 144 MHz) ham radio transmitter on my workbench into a dummy antenna load while playing background music from a streaming source coming through my PC to an NAD integrated amp and through some small Polk speakers I had in my workshop. All well and good, but when I engaged the 400 watt RF amplifier in the transmitter, the PC/NAD/Polk audio system emitted a loud hum for less than a second; the B+ fuses on the NAD's output stage opened because the output devices shorted. This sent DC to the speakers and the voice coil of one woofer opened up. This was caused by RFI driving the amplifier crazy. An extreme case, to be sure, but if you are **VERY** near an FM or AM station, or an amatuer radio operator, or a medical diathermy machine or an arc welder, you might well experience anything from crackling or other noises to strange hums to outright amplifier failure. RF can get into gain stages in many ways and if your audio system is really near a powerful RF source it can be the most devilish thing to cope with. RF power levels decrease as the square of the distance (in general) so if you are farther than a few hundred feet from any such source you shouldn't have any problems - with the exception of truly powerful broadcast equipment in which case a mile or more might be better.

 

[respice finem]

Mine are GLS brand 12 AWG with Neutrik speakON connectors. No fancy cable geometries here. Just a plain pro audio cable. Cuz the electrons don't seem to care.

Tom

Those are the so called constipated electrons (they don't give a sh!t)

 

[voodooless]

You all know where this goes now: @amirm just confirmed everything "they've" been saying: it can bleed through, so does impact the signal

You just can almost never win this... Doesn't mean we should not keep trying though!

 

[respice finem]

#23: But, even in that extreme scenario, would a different speaker cable have saved the woofer?

 

[Doodski]

Well done @amirm. Keep pushing down the fallacies that some people perpetuate. Too often the snake oil people and their followers are using a mentality of post hoc ergo propter hoc or "After this, therefore because of this." A simple example is, "The rooster crows immediately before sunrise; therefore the rooster causes the sun to rise." In time there will be less of the snake oil and more of reality.

 

[johnnyx]

[QUOTE="

RF usually enters audio circuits via the input, not the output as the output has much lower impedance.

Tom[/QUOTE]

A BBC engineering manager said the same thing to me, but low impedance for audio frequencies does not infer low impedance for radio frequencies. I had quite an argument with him. The fact is, the interference came in through the speaker cables, the input cables being already well shielded and the inputs well filtered.

 

[oupee]

@amirm
what speaker cables do you use with Revels?

 

[respice finem]

...In time there will be less of the snake oil and more of reality.

Not going to happen, I'm afraid, at least not with the hardcore "believers". Another trick they use is, they more or less require others to prove that "they don't hear what they hear", which is obviously impossible, the brain is where the hearing reaches our consciousness, and it's playing its own games. That may go as far as hearing voices that don't exist... "Doc, I had to shoot the sheriff because the voice of God told me to"... Or they say "I hear a difference so your method must be flawed, your turn to prove it isn't". So, probably sooner we have no LF analog speaker cables any more, because all is digital/active one day, than this dies out. But if we can prevent new "victims" on the way, it's already a gain.

 

[ctrl]

Great work @amirm!

What would be the worst device to receive RF in a room?

A device that is large, free standing in the room and uses meters of unshielded cable - disastrous!
And if that happens to the tweeter, man, all is lost.


Source: GR-Research, NRD

The next big thing: rewiring speakers with thumb-thick high-end cables!
Here are the first enthusiastic comments from users
.

 

[abdo123]

i live on the 15th floor and the building is even on a hill in my city (not sure if this is relevant). Whenever i use unbraided cables i hear Radio channels faintly (random music, random channels) in my speakers. It’s basically radio tweeter hiss and it’s really annoying when nothing is playing.


I haven’t watched speaker cables dude video but the part you captioned only compared braiding and this is indisputably important specifically signal wires before amplification as the radio signals will get amplified as well and become audible.

 

[Rja4000]

Hi Amir
That's good to see you in real.

Other than that, I'm sorry to say I see no point in those videos.

You ask me to spend 17 minutes on a message you could have made readable (without video) in 2 minutes.
On top of it, I need to turn sound on, so I can't get the content everywhere, as I would do with text.

What's the use ?

 

[voodooless]

What's the use ?

Last time I checked, your not the only one in the world. Clearly, these video's are not for you. I bet not even for most of the loyal ASR readers. A lot of the high-end crowd however are very keen on getting their "information" from Youtube reviewers. I think it's fantastic to hear a different voice in the crowd! And it looks like it's working, as seen by the stir the first few videos have made.

 

[restorer-john]

Hi Amir
That's good to see you in real.

Other than that, I'm sorry to say I see no point in those videos.

You ask me to spend 17 minutes on a message you could have made readable (without video) in 2 minutes.
On top of it, I need to turn sound on, so I can't get the content everywhere, as I would do with text.

What's the use ?

Unfortunately I have to agree with this.

Amir can, and should do better than a simple "attack video" on someone else. It's tacky and cheap. The temptation to be a 'hero' debunker and 'mythbuster' should be avoided. Let the actual measurements and data stand on their own.

The procedures and test parmeters by both parties leave much to be desired. No conclusions whatsoever can be determined from each "experiment".

Disappointed.

 

[Rja4000]

Last time I checked, your not the only one in the world. Clearly, these video's are not for you. I bet not even for most of the loyal ASR readers. A lot of the high-end crowd however are very keen on getting their "information" from Youtube reviewers. I think it's fantastic to hear a different voice in the crowd! And it looks like it's working, as seen by the stir the first few videos have made.

Thats is very clear, indeed.

Amir was asking for feedback.
He now got mine.
Which is valid for me only, for sure.
But not less valid than anybody else's.

 

[restorer-john]

Last time I checked, your not the only one in the world. Clearly, these video's are not for you. I bet not even for most of the loyal ASR readers. A lot of the high-end crowd however are very keen on getting their "information" from Youtube reviewers. I think it's fantastic to hear a different voice in the crowd! And it looks like it's working, as seen by the stir the first few videos have made.

So, since when did "loyal ASR readers" actually have to ascribe to a particular set of beliefs?

 

[Rja4000]

There are also things that can not easily be translated in text or static photo.

As an example, how a product really looks like, how easy it's to operate.
Or if you have an unstable measured signal.
All those could be useful support to current reports in some cases.

My request is: don't replace good text reviews by videos.
And if you add videos, keep them short
As you do so well with reviews.

Another example: create a video showing how measurent is done.
This is unique here. And could also give an idea of how long it takes.
And attach the link to each review instead of the lengthy introduction to measurement in each speaker review, as an example.

 

[respice finem]

So, since when did "loyal ASR readers" actually have to ascribe to a particular set of beliefs?

I probably misunderstood you somehow - but, since when are measurements "beliefs"?

 

[YSC]

for the cable noise pickup I remember when I was a student 20 years ago with a crap pair of Altec Lancing 5.1 speakers with really thin and not isloated cables with satellite speakers shows no sign of shielding, when I put my Nokia phone beside them any phone call will stimulate them to produce some morse code like noise before the phone rings, I believe that's when these kind of shielding cable marketing starts