I recently purchased a Trifield EMI (Dirty Electricity) Line Meter to measure noise coming from my outlets. To my surprise, my $500 power conditioner (name withheld to protect the potentially innocent) appears to not filter any noise per the Trifield readings. In fact, with some of my outlets the measures are higher through the conditioner’s outlets, than the measures coming straight out of the wall. The manufacturer denies anything is wrong with their conditioner, claiming the Trifield is measuring the wrong frequencies. Can anyone explain?
... my $500 power conditioner (name withheld to protect the potentially
innocent) appears to not filter any noise per the Trifield readings. In
fact, with some of my outlets the measures are higher through the
conditioner’s outlets ... Can anyone
explain?
It's difficult if not impossible to offer any meaningful suggestion without knowing more. Telling us it's a "$500 power conditioner" tells us nothing.
Yes, unfortunately a lot of products sold are a bad joke. Your house is separated from the grid by a transformer. Any irregularities are coming from the other houses connected to the same transformer. Remember the main line is 8 KV or more. If you want the absolute cleanest power possible you need a large bank of batteries and a good inverter. You could drive your system with solar panels. Just stay away from class A amplifiers. All this stuff about power cords, conditioner and fancy outlets is nonsense. Spend your money on a better amplifier or cartridge. This will make much more of an improvement in your system. Audiophiles are extremely gullible and the market takes advantage of this big time. If you want to spend a lot of money making your system look nice wonderful but don't think anything is going to sound better. It is not.
Frankly, I heard a substantial improvement in SQ, then I realized I had the meter. It seemed to confirm, In a measurable way, the increase in SQ I was experiencing.
You are measuring starting at 20 kHz and going up. That is, these devices START measuring noise at the upper limit of human hearing.
It's hard to imagine noise on your line only affecting one portion of the frequency range. So in other words if you reduced noise that's being measured above 20khz why wouldn't you expect that same filtering to affect the entire range even in areas that aren't being measured by the meter? Do they make current filters that reduce noise between 100hz and 1Khz??? (for example) That makes zero sense to me.
It’s hard to imagine noise on your line only affecting one portion of the frequency range. So in other words if you reduced noise that’s being measured above 20khz why wouldn’t you expect that same filtering to affect the entire range even in areas that aren’t being measured by the meter?
This problem is kind of a Venn diagram. A conditioner which starts at 10 kHz will hopefully also clean up 100 kHz. A conditioner which starts working at 100 kHz won't necessarily clean up 10 kHz.
Of course, coupling can occur later, and there will be a frequency high enough that it stops working at too.
So, you have a meter which measures RFI, which shows reduced noise, and the power conditioner happened to reduce noise in the audible spectrum too. That's luck.
Before I got my Audioquest Niagara 1200, I read where a lot of manufacturers of conditioners go for a change in sound, rather than good filtering of AC hash on the line.
But to go so far as to discredit all makes of power conditioners is silly. I haven't personally measured the noise on my lines since installing the Niagara 1200 but I've seen demos online showing the differences with noise sniffers and meters and it works as advertised.
In fact, it's probably the single biggest gain with a "tweak" I've experienced. I hadn't realized how much filth there was on my incoming AC.
My point to all of this is that cleaning up AC noise in the audio frequencies is as important or more than RFI. We should be looking at devices and measurements which clean up both.
Think of most power conditioners as essentially filters, much like the crossovers in a speaker. Signal comes in, some passes, some gets blocked. The ideal power conditioner (as opposed to a regenerator) passes 60 Hz (or 50 depending where you are) and blocks all others. RFI filters are low pass filters. If you can go lower, and start at 3-10 kHz that's better than starting at 100 kHz.
Notice I'm not talking about any brands you may like or not like. I'm just stating principles.
In your recent responses, you say RFI. We are referring to EMI.
My bad.
What I hear ain't luck. Having a device that can measure what I hear ain't luck.
Coincidence and bias are real, which doesn't mean you haven't done enough experimentation to eliminate them, they are just the first to things to eliminate before claiming more.
That's really high my friend. Mine on either dedicated line is now measuring around 220. When you achieve a lower level, you will be surprised at the increase in SQ.
I guess I never thought that hash on the AC line was associated with any frequency....I assumed it was an equal opportunity offender of all frequencies regardless of where you were measuring the dB reduction.
Uh, RFI and EMI are the same thing. Usually up in the mid-high MHz and low GHz frequencies, you know, radio waves, electromagnetic waves. When you ASSUME something you make a fool out of me and Uma Thurman.
A point to keep in mind, which I would expect to be particularly important in the case of class AB and class D power amps (since their AC current draw fluctuates significantly with the dynamics of the music), is that AC current is drawn mainly in the form of narrow spikes, occurring during just a fraction of each 60 Hz period. Specifically, when the instantaneous voltage of the incoming AC waveform exceeds the voltage on the storage capacitors by the small amount that is sufficient to turn on the rectifier diodes.
The spectral composition of that current draw therefore includes frequencies that are much higher than 60 Hz, and filtering those higher frequencies out will tend to adversely affect perceived dynamics and other sonic characteristics. Which is no doubt a major reason why many audiophiles prefer to plug power amps directly into the wall outlet.
In fact Ralph (Atmasphere) has stated in past threads that in many cases these desirable frequency components can range up to several tens of kHz, and I have no reason to doubt that. And if I recall correctly Shunyata has a paper in which measurements are presented supporting that conclusion.
On the other hand, though, it is certainly possible that noise frequencies that are higher than 20 kHz can have audible consequences, by coupling into various circuit points within the components and via effects such as intermodulation and AM demodulation. So as usual in audio tradeoffs are involved. Too low a cutoff frequency will filter out desirable spectral components, and too high a cutoff frequency may not provide an optimal amount of noise filtering. And that tradeoff figures to be dependent on the designs of the particular components and on the spectral composition (i.e., the frequency components) of whatever noise may be present on the incoming AC. Which makes it all very unpredictable.
One thing I would feel confident of, though, is that a simplistic measurement of overall noise amplitude (the noise presumably consisting of a vast number of different frequency components, with most of them differing widely in amplitude and also in terms of their potential to have sonic consequences) probably doesn’t mean much.
And, Radio frequency (RF) is the oscillation rate of an alternating electric current or voltage or of a magnetic, electric or electromagnetic field or mechanical system in the frequency range from around 20 kHz to around 300 GHz. This is roughly between the upper limit of audio frequencies and the lower limit of infraredfrequencies;[1][2] these are the frequencies at which energy from an oscillating current can radiate off a conductor into space as radio waves. Different sources specify different upper and lower bounds for the frequency range.
A minor correction to my previous post: In the first paragraph when I said:
"... when the instantaneous voltage of the incoming AC waveform exceeds the voltage on the storage capacitors by the small amount that is sufficient to turn on the rectifier diodes."
I should have said:
"... when the instantaneous voltage of the AC waveform at the output of the power transformer exceeds the voltage on the storage capacitors by the small amount that is sufficient to turn on the rectifier diodes."
That applies, btw, to both the positive and negative peaks of the AC, assuming (as is usually the case) that "full wave" rectification is being used
Conventional filters will do little in actual power lines or may even amplify EMI - it is in their own specification (that is, for those manufacturers who bother to publish such specification). For a brief explanation please see this link:
https://www.onfilter.com/real-life-filtering In short, regular filters are designed to perform at 50 Ohms termination (in and out) for EMC Compliance - CE and FCC. I personally haven't met a power line with 50 Ohms impedance. In real-life applications a better impedance ratio is 1/100 or 0.1/100 (not a critical difference in reality) where 1 or 0.1 is output impedance of AC power and 100 is rough number for a load, i.e. your amplifier. It is imprecise but much more realistic than 50/50 Ohms. Since a filter is a combination of inductors and capacitors, when designed with one goal in mind to work in a 50/50 Ohms environment, this is where it "tuned" to. In actual use it either does nothing or amplifies noise. Our company (tooting my own horn here) designed filters for actual installations that we provide to the factories around the world, NASA, governments, hospitals, etc. - they are impedance-independent and essentially kill emissions anywhere they are plugged in -
https://www.onfilter.com/ac-power-line-emi-filters
OK. BLATANT ADMISSION. I am the manufacturer of the UberBUSS power conditioner. This being said here is the experience of one of my clients: Thread is on Audio Nervosa-
Check the new UberBuss with my Entech Wideband AC Noise Analyzer.
Calibraded the meter for a noise level reading of 100 on an AC outlet without the UberBuss plugged.
Plugged the UberBuss into the outlet and the noise level dropped to 50, plugged meter into the NCF outlet on the UberBuss and it dropped to .3.
Power conditioners are all snake oil and are NOT needed. The only useful purpose they may serve is for dangerous voltage protection like lightnings and such.
All amplifiers work with DC. Mains AC is converted to DC inside all amplifiers thru transformers, rectifiers, hi freq filters and smoothing capacitors. Lower wattage power amps may also have voltage regulators, which is even better. Because of this, the quality of the mains AC has virtually NO effect on the sound (the DC) if the amplifier is properly grounded and there are no ground loops. If the rectifier and smoothers are of good quality (which in most cases these days are), and proper spike filtering is also done (again, which in most cases these days are), and as long as the waverform you feed into the transformer from the mains resembles ANY kind of rough sine wave (which will be the case even in the noisiest mains supplies), everything will be fine. You may run LESS EFFICIENTLY since the transformer will not establish a proper magnetic field but the rectifiers & smoothers will take care of everything.
ALL the necessary design to make the DC as smooth as possible are ALL included in the amp itself. Noise reduction, PSSR, smoothing, ripple reduction and transient current capability are ALL included in the power supply of the amp itself. Especially with good quality amps, this is almost always a given (Like Pass Labs).
Where you need a good quality clean AC is if you are using AC motors, like synchronous and induction. These may be driving your turntable and their rotational stability and "jerkiness" is directly affected by the quality of the AC. Even then, most turntables these days internally synthesize their own AC thru precision electronics if they are using an AC motor (one of the earliest example of this is the Linn Sondek LP12 Valhalla).
Therefore, power conditioners are a complete waste of money for amplifiers.
Your statements fly in the face of long settled science.
Dude, google is your friend. Look it up: EMI ; RFI ; broadcast radiation. Halfwave rectifiers. Cell phones.......
Why does every research lab doing milspec research utilize power filtration: LASL; Sandia Labs; Lawrence/Livermore; KAFB; MIT; Stanford; NASA; DARPA; Fermi Institute; VVA; every semiconductor manufacturer on the face of the earth and on and on and on and...
You are just wrong. You are simply clueless. Do some homework. Try something.
People think this is something we understand well enough to even begin to measure. Why? The answer can only be: because you haven't even tried listening. Soon as you do, all this nonsense about measuring noise goes right out the window. To even ask the question is to show you literally do not have a clue.
LOL.... Everyone missed my point. I never argued about the EXISTENCE of noise. I simply said it is ALREADY taken care of inside the amp itself. Almost all decent amps today deal with it internally. There is NO need for an external noise filter.
cakyol God you are mad! My electrical supply is so contaminated to beggar belief. Without conditioner (now a balanced supply) my music is almost unlistenable. Just stop writing about things you have less than zero knowledge about
This keeps being repeated as "factual", when it never has been. The output of a rectifier includes DC and high frequency components. Simple transfer function analysis. The more of those high frequencies you eliminate, the greater the ratio of DC to AC. Those high frequencies can extend dynamic range of the amplifier by providing a higher minimum voltage on the capacitors, but they will never contribute to lower noise. They will always contribute to more noise.
The circuits in the amplifier or other equipment may prefer the higher voltage being designed that way (bias values, etc), but the noise is never going to be less.
For emphasis, this is a simple one way transfer function, it is not loop analysis where high bandwidth can be used to cancel noise.
The spectral composition of that current draw therefore includes
frequencies that are much higher than 60 Hz, and filtering those higher
frequencies out will tend to adversely affect perceived dynamics and
other sonic characteristics. Which is no doubt a major reason why many
audiophiles prefer to plug power amps directly into the wall outlet. In
fact Ralph (Atmasphere) has stated in past threads that in many cases
these desirable frequency components can range up to several tens of
kHz, and I have no reason to doubt that. And if I recall correctly
Shunyata has a paper in which measurements are presented supporting that
conclusion.
Generally people don't think of frequencies in the audio band (<=20KHz) as EMI, but as line harmonics. 20Khz has a wavelength of 9 miles (15km), so you need a pretty big wire for a good antenna. These EMI toys don't measure harmonics. You need a good power meter for that. They of course don't give you the spectrum either.
Sorry for all the posts, but this thread is just a wealth of misinformation. Take his 1/2 truth from onfilter.com who is trying to do what? Sell you filters
Some points: Most people add filters to their designed products not to reduce noise getting into them, but to reduce noise getting out of them to pass EMI. his part they got right.
The "standard" line impedance used for testing varies from 0.1 ohm to 0.4ohms, at low frequencies, which is not where EMI is tested. IEC60669 defines common line impedance for 230V as 0.2ohms and 400uH. North American standards for 120V are typically 0.2-0.4ohm, and 100uH - 400uh. FCC conducted emissions testing begins at 150KHz. At 150KHz, 400uH = 60 ohms, at 100uH = 15ohms. That transformer outside your house is not presenting a 0.1ohm source impedance at 150KHz. Now I am not complaining that OnFilter products don't do anything, likely they do, but they aren't being very honest with the information they are presenting. Now there are likely things in your house, i.e. motors, dimmers, etc. that because they are close have more impedance, but even 30 feet of Romex is 3-4 ohms at 150Khz.
The 50 ohms used in EMC measurement is more of a parasitic impedance, and unavoidable due to the input impedance of test equipment, and the passive setup. Technically in EMI/EMC measurement, the equipment is fully isolated from the AC and the measurement is volts.
Conventional filters will do little in actual power lines or may even
amplify EMI - it is in their own specification (that is, for those
manufacturers who bother to publish such specification). For a brief
explanation please see this link:
https://www.onfilter.com/real-life-filtering
In short, regular filters are designed to perform at 50 Ohms
termination (in and out) for EMC Compliance - CE and FCC. I personally
haven't met a power line with 50 Ohms impedance. In real-life
applications a better impedance ratio is 1/100 or 0.1/100 (not a
critical difference in reality) where 1 or 0.1 is output impedance of AC
power and 100 is rough number for a load, i.e. your amplifier. It is
imprecise but much more realistic than 50/50 Ohms. Since a filter is a
combination of inductors and capacitors, when designed with one goal in
mind to work in a 50/50 Ohms environment, this is where it "tuned" to.
In actual use it either does nothing or amplifies noise. Our company
(tooting my own horn here) designed filters for actual installations
that we provide to the factories around the world, NASA, governments,
hospitals, etc. - they are impedance-independent and essentially kill
emissions anywhere they are plugged in -
The audience here simply doesn't know much about noise, including the people fronting noise reduction technology. The subject is codified in many ways by many international organizations. It is based on a knowledge of mathematics and of many other areas of engineering. Because we are supposed to be an organization of music lovers, add our group to the subject of "noise." It isn't nearly as codified and regulated, but still covers a wide area of human reaction to sound. I am not going to say anything other than that "stupid is as stupid does." If you would like to really understand noise, it's measurement and appreciation, start with yourself. As a human being, interested in music... learn to appreciate the music, not the noise. The best filter I know is your mind. "If you don't mind, it doesn't matter."
While I don't agree with caycol in totality, a good portion of what he is stating is true at least for audio. In a well designed product, high frequency external RF noise is much easier to get rid of than low frequency noise, i.e. in the audio band on power lines, and guess what, low inductance, low capacitance AC cords are not going to help the situation, though consistency of the chassis ground reference between equipment can be critical for low noise.
High frequency RF as measured by these EMI toys does not represent well the much harder to filter frequencies on the AC line that are either in the audio band and/or close it and can sub-modulate down into the audio band.
Where the problems come in is with low level, high impedance signals such as interconnects, whose signal path may include the chassis ground due to intentional (or unintentional) capacitance between the signal ground and chassis ground (usually intentional).
piaudiol, most of the papers you linked have nothing to do with the topic specifically, which really doesn't address the effectiveness of line conditioners either where it matters, nor do they really refute caykol, though they do introduce topics such as ground loops, and hum, that my have nothing to do with EMI filtering at all.
robberrttddidd High frequency RF as measured by these EMI toys does not represent well the much harder to filter frequencies on the AC line that are either in the audio band and/or close it and can sub-modulate down into the audio band.
>>>>Sub-modulate down to the audio band? Are you high? Radio Waves are not even in the same domain as acoustic waves. How can MHz or GHz electromagnetic waves submodulate down to the acoustic band? It almost sounds like you actually think the acoustic waveform is traveling through the wires and cables.
Wow, I have seen that much jibber jabber since the last time I squeezed your head. You don’t get audio frequencies until the speaker diaphragm moves. Then you get audio, Mr. Smarty Pants. 👖Up until the signal gets to the speaker there is no audio, only current and voltage.
I got an Audioquest Niagara 1200 and use Audioquest Tornado High Current and Source AC cables. I also installed an Audioquest Edison Duplex AC wall outlet. I have no measuring device to test my wall AC outlet noise (though I did the research and both read and viewed the metered difference of AC noise before and after the Niagara 1200 was inserted). What I can say is that my system sounds far more dynamic and clean, than ever before. The concept and the product work exceptionally well. My ears told me so. 'Nuff said...
Wow. Just, wow. Seems like every discussion on audio brings out the worst in people: those who decry things due to, measurements, and those who actually use their ears and report their findings.
Then comes the acrimony, the insults, the authoritarian know it alls who talk down to the less well versed, but better listening crowd.
It's why I've taken to posting a whole lot less as this place has been taken over by the same breed as the YouTube crowd. Anyone notice how many audio review sites no longer have a comments section or have simply stopped online publishing?
Too many ids unleashed thanks to the internet. If those thoughts and words could be manifested, we'd destroy ourselves overnight, like the Krell did in Forbidden Planet.
@roberttdid Regarding your recent post in which you quoted from my earlier post: I agree with everything in your post, except that I don't see any inconsistency between your statements and my statement which you quoted.
Keep in mind that what I was addressing was noise filtering that would be applied to the incoming AC by a power conditioner, not filtering provided at the output of a rectifier circuit or anywhere else within an amplifier or other audio component.
I understood that you meant AC filtering. I am calling into question the need for the high frequency components on the AC line, other than to maintain the supply rail voltage post rectification. I don't agree that filtering out those frequencies will have an adverse impact on dynamics, other than as it would impact the rail voltage after rectification. If anything, an amplifier with adequate capacitance, designed to reduce as much of those high frequency components as possible (hence why chokes, etc. are often added to to the circuit to reduce high frequencies) would have lower noise and distortion and be able to more accurately portray dynamics.
The spectral composition of that current draw therefore includes
frequencies that are much higher than 60 Hz, and filtering those higher
frequencies out will tend to adversely affect perceived dynamics and
other sonic characteristics. Which is no doubt a major reason why many
audiophiles prefer to plug power amps directly into the wall outlet.
So what was this @geoffkait , lazy reading, excessive trolling of every post I make, or did you not understand what I posted.
1)
High frequency RF as measured by these EMI toys does not represent well
the much harder to filter frequencies on the AC line that are EITHER IN
THE AUDIO BAND AND/OR CLOSE (to) IT and can sub-modulate down into the
audio
band.
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