Surprised at Low Household EMI Readings

I second the comment of the other member asking about the correlation between EMI and dirty/noisy AC. I thought EMI was generally caused by source cables being too close to power cables which interfere with the source cables via electro magnetic "induction" whereas dirty AC is either coming in from the utility company that way or there are appliances/components in the house that are (often having a motor of some sort, or, in my case a Keurig coffee machine) pushing DC or some other signal back into the line that is then being presented as a hum in the audio system. My home has a steady low level hum in the AC that regardless of which circuit I use, can be heard on most audio systems I have around the home. It must be coming in from the utility or there's one appliance plugged in somewhere thats polluting the entire electrical system. 

One of the first things I learned when I started pursuing high end audio was to listen first and... well, over time was to ignore most measurements. There are so many variables that to isolate a couple and attribute the results to them will be too confounding to be helpful. I was trained and professionally a scientist for a decade. 

If you want to put together a great sounding system then looking for measurements and applying logic, then making purchases is dead end. You will end up with a very mundane uninspiring sounding system. Listen to well seasoned audiophiles and use observation as you primary tool. 

jaybe

... What other nasties live might live in my power and how can they be detected? ...

You could argue that any deviation from a perfect 120VAC 60 Hz sinewave is "dirty" power. You could observe that on an o-scope.

@sns funny guy. good to know when condescension is called for, you’re the go-to.

Just went around house with my Trifield meter taking readings from various outlets, amongst the outlets measured were whole house, dedicated lines to my audio system, lines coming out of my power conditioner (transformer based), whole house lines with Audio Prism Quiet Line filters. Whole house with or without the filters and dedicated lines measured pretty much the same, lines out of my transformer based PC measured higher.

So, based on these measurements we can deduce my dedicated lines, the filters worthless, and those coming out of PC are less than worthless. Or we can deduce these readings not telling us much of anything. On the other hand, subjectively, these dedicated lines and power conditioning  have greatly reduced noise floor of my audio system, a great number of audiophiles report same with their dedicated lines and PC's. One can choose to believe the Trifield meter as the objective arbiter of noise on AC lines or they can choose their senses.

So some 

I was led to believe that if I had low EMI then my AC power was fairly clean. Others here seem to think otherwise. Please elucidate if this is incorrect. What other nasties live might live in my power and how can they be detected?

@sns not talking about RF

@ghdprentice no plans to install new lines

@dekay or bribed the admins to block you

Thank you for sharing!

For $150 you could have moved to Des Moines.

DeKay

I would be willing to bet that you would hear a substantial improvement by installing direct lines and also by upgrading power conditioner... and depending on your equipment installing audiophile duplex receptacles.

I don’t think in my fifty years pursuing the high end has measuring one or two variables ever told much of the story. 

Go to a dealer, borrow a top of the line power conditioner. Now that is a appropriate test. 

I too don't see any correlation to the need or not for power conditioner. I have Triifield meter, most useful in audio systems to measure for RF and EMF. I my case in which I have modem and router close to audio system, extremely high levels of RF led to me disabling wifi for what now serves as my audio only router, adding a second wifi enable router located  some distance from audio system serves as whole house router, RFI leakage or contamination of other equipment is a concern. EMF leakage from  transformers is another concern, these should be shielded so as to not contaminate sensitive circuits in equipment.

AC circuits are noisy for a whole host of reasons, much due to the many switch mode power supplies on modern electronic devices, thus, the reason for dedicated circuits for audio. Dedicated circuits alone generally not enough, most find noise floors further diminished via power conditioners. I don't believe any Trifield meter is going to serve as qualified arbiter as to whether you will benefit from power conditioner or not.

EMI is something that I never noticed.... until it wasn't there.  Probably my 70 plus year old ears.

@noromance 

thanks for dropping by

Not sure what the correlation you are seeing comparing low EMI with the challenge of dirty 110v power.

@jaybe good pragmatic use of your money