EMI/RFI radiating from Rega Elex~r integrated amp? Dimmer switches? AC-Power?

[MINOR WHITE]

Afternoon all.
I have been revamping my home theater/2.1 channel hifi with some new equipment thanks to ASR (got rid of Rega DAC~R for a Bel Canto DAC 2.8, picked up a cheap MacMini for movie/tv/and higher audio bit rate USB output to DAC)!

While doing all of these changes, I decided to change out the dimmer switch/lightswitches for regular on/off style: I could literally hear a very tiny buzz from one I sit nearly directly next to.
I think I understand that in general, dimmer switches can radiate quite a bit of EMI/RFI, whether they impact audio gear or not I am not certain, (never seen anyone do empirical measurements).
I picked up an RFI/EMI tester probe to 'hear' how much the switches were emitting before and after, and which regular ones were quiter (to get replacements of that kind) and the 'noise' was very noticeable.

While changing out the audio gear and re-vamping that system, I decided to see anecdotally if any of the audio equipment was doing same emitting of any noticeable RFI/EMI.
The probe picked up a fair bit from the Rega Elex~R integrated amp, almost as much as what the light dimmer switch was emitting.
But, if I touched the metal case of the Rega at the same time, the audible "BBBBAAAAAAAZZZZZZZ" from the probe was almost inaudible.
What is happening here? Am 'I' performing some sort of radiation frequency grounding?
(Note the amplifier itself is NOT making any mechanical nor frequency noise from the unit itself or through the speakers-meaning there doesn't seem to be any sort of 'transformer buzz/ground loop).
The Rega performs totally fine, and it doesn't have a dac in it (this is not the brand new model) so to my knowledge it is functioning like new.
Is there a point where one piece of equipment radiates enough to affect another, like the amp to the dac?
Many thanks!!

 

[MaxwellsEq]

Afternoon all.
I have been revamping my home theater/2.1 channel hifi with some new equipment thanks to ASR (got rid of Rega DAC~R for a Bel Canto DAC 2.8, picked up a cheap MacMini for movie/tv/and higher audio bit rate USB output to DAC)!

While doing all of these changes, I decided to change out the dimmer switch/lightswitches for regular on/off style: I could literally hear a very tiny buzz from one I sit nearly directly next to.
I think I understand that in general, dimmer switches can radiate quite a bit of EMI/RFI, whether they impact audio gear or not I am not certain, (never seen anyone do empirical measurements).
I picked up an RFI/EMI tester probe to 'hear' how much the switches were emitting before and after, and which regular ones were quiter (to get replacements of that kind) and the 'noise' was very noticeable.

While changing out the audio gear and re-vamping that system, I decided to see anecdotally if any of the audio equipment was doing same emitting of any noticeable RFI/EMI.
The probe picked up a fair bit from the Rega Elex~R integrated amp, almost as much as what the light dimmer switch was emitting.
But, if I touched the metal case of the Rega at the same time, the audible "BBBBAAAAAAAZZZZZZZ" from the probe was almost inaudible.
What is happening here? Am 'I' performing some sort of radiation frequency grounding?
(Note the amplifier itself is NOT making any mechanical nor frequency noise from the unit itself or through the speakers-meaning there doesn't seem to be any sort of 'transformer buzz/ground loop).
The Rega performs totally fine, and it doesn't have a dac in it (this is not the brand new model) so to my knowledge it is functioning like new.
Is there a point where one piece of equipment radiates enough to affect another, like the amp to the dac?
Many thanks!!

When you touch the box, you are offering a path to ground, admittedly high resistance. Does the amplifier have an earth wire in its mains cable?

How confident are you of the probe? There is some "sham" science in this area with companies offering probes that demonstrate "problems" which may not actually be relevant. There is always RF around and good kit should not be affected by it.

 

[MINOR WHITE]

When you touch the box, you are offering a path to ground, admittedly high resistance. Does the amplifier have an earth wire in its mains cable?

How confident are you of the probe? There is some "sham" science in this area with companies offering probes that demonstrate "problems" which may not actually be relevant. There is always RF around and good kit should not be affected by it.

Morning,
I was thinking I was acting as a ground path for the RF. The amp does NOT have a ground pin on its mains plug-in (though the power cord I am using does).
For some reason I don't think any Rega products are three prong?
There is a ground screw post on the back for turntable. I tried attaching a long speaker wire to it and could do the same thing- touch the end and the 'noise' the probe gave off attenuated.

The probe is a circuit tester/tracer, so I am 'kind of' not using as it was specifically intended, though it is often used as a 'noise probe'.
Exactly like you mentioned, I am not saying there is something 'wrong' or malfunctioning (and I would bet I am creating a "problem"!)
I was just curious if I could help lower any stray noise from the components. I did the same test with an old Adcom GFA-555 (212watt dual mono amp) and it's 'noise' was dramatically less than the Rega.
I found this video this morning and it shows nearly exactly what I am doing:

 

[MaxwellsEq]

It's possible that the device with an earth cable is screening the internal RF better. However, I don't think your methodology will be demonstrating anything that would have any audible impact.

 

[Chrispy]

Curious, how did you come across this use of this device? That guy in the video has some questionable stuff in his choice of power cords/outlets....I smell audiophoolery.

 

[NTK]

Looks like it is a tool for network cable tracing. Link is to a newer (current) version of the device.

AMPLIFIER PROBE - TREND Networks

Amplifier Probe for Data Cable Tracing

www.trend-networks.com

 

[MaxwellsEq]

Looks like it is a tool for network cable tracing. Link is to a newer (current) version of the device.

AMPLIFIER PROBE - TREND Networks

Amplifier Probe for Data Cable Tracing

www.trend-networks.com

Ah. Not a useful tool for testing audio then.

 

[MINOR WHITE]

Curious, how did you come across this use of this device? That guy in the video has some questionable stuff in his choice of power cords/outlets....I smell audiophoolery.

There are several electrical engineers/designers who use RF "sniffers" or probes to trace noisy components, stray signals, etc.
Some can be attached to an oscilloscope to trace exact frequencies, etc.
The one the person uses in the video is just a cable networking tracing probe, but it also picks up 'emi/rfi' to a non-precise degree.

Fairly complex proper probe

 

[Chrispy]

There are several electrical engineers/designers who use RF "sniffers" or probes to trace noisy components, stray signals, etc.
Some can be attached to an oscilloscope to trace exact frequencies, etc.
The one the person uses in the video is just a cable networking tracing probe, but it also picks up 'emi/rfi' to a non-precise degree.

Fairly complex proper probe

Probe itself aside, how did you come across this "technique" with one for audio purposes? Hope it wasn't from this doofus whose video you posted. I just looked at another of his posts extolling the power cable thing, which is nuts.

 

[NTK]

The Rega Elex-R is an IEC Class II device, and does not have or need a safety earth ground connection.

It is quite normal to have a voltage potential of many tens of volts in the metal chassis of a Class II electrical/electronics device. Because it has no connection to earth ground, the chassis is electrically floating and there is no path to the earth ground to dissipate the electrical charge. The stray field (from transformers, inductors, wires, PCB traces, etc.) can induce an easily detectable voltage potential in the chassis. It is somewhat similar to the static electricity build up on our bodies in very dry environments, such as if we wear shoes with rubber soles and rub them rigorously on the carpet. So it is of no surprise for a probe to show some readings that go away when you ground the chassis, and it should not be a big cause of concern.

Below snip is from:

Class II product: is it safe to measure high voltage between SELV output and earth? - Mascot Blog AS

Mascot - blog

www.mascot.no

 

[DonR]

The Rega Elex-R is an IEC Class II device, and does not have or need a safety earth ground connection.

It is quite normal to have a voltage potential of many tens of volts in the metal chassis of a Class II electrical/electronics device. Because it has no connection to earth ground, the chassis is electrically floating and there is no path to the earth ground to dissipate the electrical charge. The stray field (from transformers, inductors, wires, PCB traces, etc.) can induce an easily detectable voltage potential in the chassis. It is somewhat similar to the static electricity build up on our bodies in very dry environments, such as if we wear shoes with rubber soles and rub them rigorously on the carpet. So it is of no surprise for a probe to show some readings that go away when you ground the chassis, and it should not be a big cause of concern.

Below snip is from:

Class II product: is it safe to measure high voltage between SELV output and earth? - Mascot Blog AS

Mascot - blog

www.mascot.no

View attachment 334839

Absolutely. I had a Logitech 2.1 speaker that was exhibiting some noise and discovered an 11V potential difference which disappeared once the circuit was earthed. I suspect the cheap transformer in the linear supply. My Juntek aka Junk-tech sig gen had a 40V difference!

 

[MINOR WHITE]

The Rega Elex-R is an IEC Class II device, and does not have or need a safety earth ground connection.

It is quite normal to have a voltage potential of many tens of volts in the metal chassis of a Class II electrical/electronics device. Because it has no connection to earth ground, the chassis is electrically floating and there is no path to the earth ground to dissipate the electrical charge. The stray field (from transformers, inductors, wires, PCB traces, etc.) can induce an easily detectable voltage potential in the chassis. It is somewhat similar to the static electricity build up on our bodies in very dry environments, such as if we wear shoes with rubber soles and rub them rigorously on the carpet. So it is of no surprise for a probe to show some readings that go away when you ground the chassis, and it should not be a big cause of concern.

Below snip is from:

Class II product: is it safe to measure high voltage between SELV output and earth? - Mascot Blog AS

Mascot - blog

www.mascot.no

View attachment 334839

Thank you so much for taking the time to help me with this, and the really helpful information.
I'm not sure why Rega would set things up with out the earth ground - I had always assumed that all electrical devices (especially an amp) would/should have an earth ground.
I'll read thru the extra link you provided, I am pretty sure I can work out most of it.
Thank you again!

 

[MINOR WHITE]

Absolutely. I had a Logitech 2.1 speaker that was exhibiting some noise and discovered an 11V potential difference which disappeared once the circuit was earthed. I suspect the cheap transformer in the linear supply. My Juntek aka Junk-tech sig gen had a 40V difference!

That's so funny you mentioned the computer speaker system. I had forgotten I had a Cambridge Soundworks 2.1 (I think was designed by Henry Kloss?) back in early 2000s that did that as well and I never knew why.
Drove me nutz.

 

[MaxwellsEq]

Thank you so much for taking the time to help me with this, and the really helpful information.
I'm not sure why Rega would set things up with out the earth ground - I had always assumed that all electrical devices (especially an amp) would/should have an earth ground.
I'll read thru the extra link you provided, I am pretty sure I can work out most of it.
Thank you again!

It doesn't need it. Your car doesn't have an earth cable, yet the radio works. Your cellphone doesn't have an earth cable, but you can play music on it and call friends.

 

[antcollinet]

Thank you so much for taking the time to help me with this, and the really helpful information.
I'm not sure why Rega would set things up with out the earth ground - I had always assumed that all electrical devices (especially an amp) would/should have an earth ground.
I'll read thru the extra link you provided, I am pretty sure I can work out most of it.
Thank you again!

The reason for earth ground is electrical safety.

There are two ways of providing that safety. One is by earthing the chassis so that if a fault causes the chassis to be connected to mains live, the dangerous current shorts to earth, and blows the fuse or trips the circuit breaker - safety issue gone.

The second way is to provide double insulation (also called reinforced insulation) between mains voltages and anything the user can touch. In this way. you have to have two separate faults for a dangerous situation to exist.


It has nothing to do with audio performance. Though it can influence audio system performance (for example, via ground loops)

 

[MINOR WHITE]

The reason for earth ground is electrical safety.

There are two ways of providing that safety. One is by earthing the chassis so that if a fault causes the chassis to be connected to mains live, the dangerous current shorts to earth, and blows the fuse or trips the circuit breaker - safety issue gone.

The second way is to provide double insulation (also called reinforced insulation) between mains voltages and anything the user can touch. In this way. you have to have two separate faults for a dangerous situation to exist.


It has nothing to do with audio performance. Though it can influence audio system performance (for example, via ground loops)

Thanks so much for this info. I guess that is what was confusing me about the 'ground' for the chassis: why a manufacturer wouldn't have to take advantage/use of that route in case the case were to be electrified. But I think I am understanding that now. I'll watch Amir's video on earth/ground to get some more awareness.

 

[Speedskater]

The primary purpose of the Safety Ground/Protective Earth wire/circuit is for safety during 'Ground Fault (short circuit) events.
It will trip a circuit breaker/fuse if the Hot wire shorts to the chassis.
It will also hold the chassis's and shields to near the same potential.

The wire from Planet Earth to the building's service entrance /main breaker box is for safety during thunderstorms and other high voltage failures.
Like a broken tree branch causing the 10,000 Volt power line to fall on your 240 Volt line.
An added connection to Planet Earth will not reduce an interference.noise problem.

 

[MINOR WHITE]

The primary purpose of the Safety Ground/Protective Earth wire/circuit is for safety during 'Ground Fault (short circuit) events.
It will trip a circuit breaker/fuse if the Hot wire shorts to the chassis.
It will also hold the chassis's and shields to near the same potential.

The wire from Planet Earth to the building's service entrance /main breaker box is for safety during thunderstorms and other high voltage failures.
Like a broken tree branch causing the 10,000 Volt power line to fall on your 240 Volt line.
An added connection to Planet Earth will not reduce an interference.noise problem.

Thanks for taking time with this! Very helpful. I watched Amir's video on grounding and am really grasping all of it now.

 

[MaxwellsEq]

Next up, I recommend reading Bruno Putzeys' article "The G Word"

 

[antcollinet]

Next up, I recommend reading Bruno Putzeys' article "The G Word"

I agree. I wish I'd known about it significantly before retirement

https://www.hypex.nl/media/fa/d8/a3/1682342122/The%20G%20word.pdf