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Greenwave 2500i AC Filter Review

Rate this AC Filter

  • 1. Waste of money (piggy bank panther)

    Votes: 127 83.6%
  • 2. Not terrible (postman panther)

    Votes: 13 8.6%
  • 3. Fine (happy panther)

    Votes: 12 7.9%
  • 4. Great (golfing panther)

    Votes: 0 0.0%

  • Total voters
    152

Matias

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I'd also like to see iFi filters measured, their claims are quite strong
Amir only measured its effect (or lack thereof) below, but I am curious about the actual AC filtering and other devices like other DACs or amplifiers even.

 

fpitas

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Taking the DIY approach and washing my outlets today (2 parts water, 1 part dish soap, 1 part baking soda).
The best way to get clean power.
 

GXAlan

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Absurd claims.

But, it shows a measurable effect even on a high end Topping 90 series product which is impressive to me since a lot of other power products do nothing.

I think of it like a car wash. The car wash doesn’t do anything for fuel economy or rust prevention, but if gear is part of the hobby and not just listening, this $35 seems to do something and not be dangerous.
 

YSC

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The health problem is funny as.... __insert your curse here

if normal AC power is so troublesome it would be mandatory for out of power factory filter long long ago..
 

Sokel

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Strange thing (except if that is normal) is that reduced second harmonic too but not the third.

Thanks Amir!
 

SuicideSquid

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I voted "Not Terrible" on this because, unlike so many "audiophile" tweaks, it actually does *something*, and it's not expensive. I'd never actually bother to put one in my system or recommend it to anyone else, but as far as audiophile tomfoolery goes, this is about as innocuous as it gets.
 

phoenixdogfan

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Maybe if John Hinkley bought a whole bunch of these and installed them all in his house that high pitched ringing in his head would stop.
 

D700

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Conclusions
... Whether it does something for your health, I leave that to your common sense.
I bought 3 of these to stop AM radio reception through the fillings in my teeth. Beats the hell out of tinfoil hats. I only wish they made them for my car.
 

Kaameelis

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Was filtration measured when only load for filter was AP input impedance?
If yes, this is not very correct way of measuring filter.
 

delta76

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From this image in your review this is a scam that can have deadly consequences because people could not get proper medical treatment in time.

While the usual audiophoolery is relatively harmless, the claims below are not.

This is far worse than a waste of money.

index.php
they should have charged $3500, not $35 for such claim ...
 
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Shadow12347

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While not particularly helpful for audio, I wouldn't jump to conclusions about health so quickly. EMI actually is harmful, and electronics should be designed to reduce it's emission/transmission as much as possible. Here's an article from Cadence on EMI and its relation to PCB design:


In the article many of the tests for compliance indicate a range starting from as low a frequency as 150khz. This filter does seem to eliminate a spike around 700khz (at least that's what it looks like in the graph, but please correct me if I'm wrong Amir), and another one right around 150khz which both fall within the range of some of these tests. I'm not qualified to say whether or not such a device can improve health, but as Amir showed, this device did also result in another reduced high frequency spike (albeit out of the range of tested frequencies from the article) that did still make its way into the output of a well filtered device. The level is already so low that it's completely inconsequential for anything really, but remember this is, as Amir has already stated, a device that already has good filtering. This has demonstrated that it is possible for HF noise to make it to a device's output, and even one that is well filtered, so using this product on a a high powered device/appliance that has poor or no filtration at all might actually make sense. I emphasize that I say MIGHT. Again, I'm not qualified to say with certainty whether or not this device actually is beneficial for health, or if it makes sense to buy them, but it at least does make a measurable difference at frequencies that fall within the range of testing for EMI compliance... I do personally find the claims a bit hysterical, and doubt whether the device's effects are of any consequence to health, but the testing does indicate that it is doing somethign for its INTENDED purpose.
 
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amirm

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Was filtration measured when only load for filter was AP input impedance?
If yes, this is not very correct way of measuring filter.
It wasn't tested like that. The outlet you see is for auxiliary use/convenience. It is not needed in typical use. The filtering is parallel to the outlet you plug it into and is meant to clean up that circuit. Company actually recommends using a number of these in each room for that reason. Given this, I plugged the filter into my power strip which was also used by my computer, audio precision, etc. I then instrumented the impact using a spare outlet on the same power strip. In this regard, you absolutely want the input impedance of the instrument to be high as to not load it up artificially. The filter saw what it would normally sees (i.e. all the loads that were active on that power strip). Measurements correctly show the impact of the device.
 
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amirm

amirm

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Despite the very dubious marketing claims, it does actually filter. A little. And $35 isn't exorbitant.
On this, they highly encourage people to buy multiple. On Amazon, the listing for is $140 for a bunch of them. And owner bought a large set as well. So while it is not expensive by audio filter standards, buying a bunch of them does cost good money.
 

restorer-john

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I think of it like a car wash. The car wash doesn’t do anything for fuel economy or rust prevention

My car always drives better and goes faster after I've washed it.
 

AndreaT

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It might be worthwhile to investigate whether the FDA or the FTC might be interested in the health benefits claimed in the advertising of this useless junky piece of equipment. As I wrote, preying on people with chronic diseases with the illusion that one of each for every electric outlets might improve insulin requirements, ameliorate a plethora of other diseases adds a tragic dimension to quackery, IMO. Not everyone has an education sufficient to disregard such claims.

Thank you Amir for showing us no possible audible benefits of this filtering box!
 

GXAlan

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My car always drives better and goes faster after I've washed it.
Australia and New Zealand are unique cases since your car washes are essential for washing away the giant spider eggs and cobwebs which disproportionately add performance robbing weight relative to the reduced vehicle mass of your Ute.
 

617

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Dirty Electricity? Isn't that a Stooges album?

Also it's only $35. Yes it doesn't do anything, but there are a lot of more useless products out there which cost more than $35. It's a bargain in a sense.
 
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