New Head-Fier
Pros: Nothing
Cons: Everything
I would have given it 0 stars but there's no option for that...
A friend of mine sent this to me for testing a week ago. In short, it doesn't do anything other than waste power in the mains socket.
I placed it in the power strip that powers my PC, PC Monitor and Lynx Hilo DAC/ADC and, as recommended by iFi, also in one of the mains sockets where the power strip is connected to.
At first, as I always do, I listened to my DAC and AKG K812 combo with and without the AC Purifier in place. I couldn't tell a difference.
Next I measured the analog outputs of the Lynx Hilo with RMAA (Line Out, Monitor Out, Phones Out) and again, not a single difference appeared in the graphs.
And no, it didn't improve my PC Monitor's picture either :)
It saddens me to see how gullible most people are...Yes, very few of us have technical backgrounds in science or engineering, but at least ask yourself simple questions such as why and how such a device can make a difference?
All properly designed audio/video equipment have power supplies that deliver stable DC voltages to their signal stages and no "ac purifier" can change the measured analog output signal. If it did, that AV equipment would be terribly designed and you wouldn't buy it in the first place.
I whole-heartedly disagree with everything you stated in your "review". From the moment I plugged the AC iPurifier into my power strip I noticed an improvement, one that went away when I yanked it out of the socket. For you I recommend a box of Q-tips!


Pros: More consistency, lower noise level, greater realism in music
Cons: Not ideal for every setup. It's better to have a well equilibrated audio system first.
This unit has been lent for review by iFi Audio and AT Consumers. By no means the thoughts and insights portrayed in this review are biased. These are my honest thoughts about it.


The iFi AC iPurifier is a compact, high-tech device that exhaustively reduces the noise of that power outlet into which you plug in your audio equipment.


How does it work?:

You plug it to the AC mains wall outlet that supplies the audio system or into the mains extension block for the audio system separating analogue digital equipment, and it automatically takes samples of the current from your socket to perform an optimal filtering.

Through the ANC technology (Active Noise Cancellation) and WPS (Wireless Purification System), the AC iPurifier calculates and sends a signal back to the socket that cancels the perceived noises. On the other hand, it protects the equipment against voltage surges, detects lack of ground in the system and if the polarity is correct. And if that were not enough, it has an intelligent ground connection (Intelligent Earth) that you can use to connect the ground of all your audio equipment, but it only works if necessary, further avoiding more ground loops.



All that technical section is great, but it also has a great impact on the sound of our equipment, especially with low-quality switched power supplies (SMPS) or a dirty power outlet. There is greater realism in the music, greater consistency and a lower ground noise. Of course, if our audio setup had hiss, it will still have it, although it will be much more consistent and less accentuated.


I tried the two configurations suggested by iFi and the second one proved to be more effective (in the middle of the strip). I own a somewhat rudimentary analogue equipment (amplifier and speakers) (a JVC UX2000RGD) that shows hiss at high volume but in the digital section I use an iFi iGalvanic3.0 (provided by AT Consumers ) next to my iFi micro iUSB3.0 and connected to my iFi micro iDSD with some great Meze 99 Classics. The results have been conclusive although I was somewhat skeptical at first.


During this time testing it, I have appreciated more consistency in sound and something more body in music. About the noise level, maybe I notice it a tad minor but it is difficult to appreciate in my headphone setup, since the iGalvanic3.0 and the micro iUSB3.0 fulminan any noise. Through my speaker system (the JVC) I perceive that reduced noise level and greater realism much more clearly.



If you have a Mid to High-End audio setup, the AC iPurifier is a great tool for improving consistency and realism in music without the need of replacing all power supplies and getting crazy at diagnosing ground and polarity issues. But don't forget that audio is like seeking a balanced and rich diet: Music is raw food, headphones and speakers are the chefs, the DAC sets the recipe, amplifiers cook the food and power supplies are the motivation and spirit behind everything. Motivation and spirit are key, but worthless without resources to take action.
Great review! My ears agree with what you stated!

Dobrescu George

Reviewer: AudiophileHeaven
Pros: Clean Power, Surge Protection, Improves found if the power was not in good shape, Solves Grounding Issues where possible, Pocket-Friendly Price for a power conditioner, Nice Design, Easy To Use
Cons: Improvements and results will vary with each system and situation, some systems are very prone to picking up noise in the mains, while others are less prone, You need to make sure you get the correct version for your country's power outlet.
iFi AC iPurifier - Power Immaculate

We reviewed quite a few types of audio devices so far, but this is the first time we dwell into a device that promises to purify the power that is fed to your audio devices. iFi AC iPurifier is here to clean your power and to give you a noise-free experience.


iFi is a well-known company from UK, part of the respected AMR group (Abbingdon Music Research). iFi has created some of the best audiophile instruments there are, like their iFi iDSD Black Label Micro, which we reviewed in the past .

We knew for a while that iFi also designs power cleaning solutions, along with products like their iEMatch and Groundhog, which further help one get the best sound possible from the audio setup they already own. This being said, we are aware that reviewing a power cleaning solution might come as slightly controversial, so we'll try to stay as technical as possible, and follow along with real-world impressions as best as we can.

It should be noted that we have absolutely no affiliation with iFi, we am not receiving any incentive for this review. This review is not sponsored nor has been paid for by iFi or anyone else. We'd like to thank Hoomairah from iFi for providing the sample for the review. The sample was provided along with iFi's request for an honest and unbiased review. This review will be as objective as it is humanly possible, and it reflects our personal experience with iFi AC iPurifier. Every opinion expressed is ours and we stand by it. The purpose of this review is to help those interested in iFi AC iPurifier understand it better and know if it is a worthwhile investment for their audio collection.

About me


First things first, let's get the packaging out of the way:

iFi AC iPurifier is packaged in one of iFi's signature packages, made by materials which are trying to protect the environment, along with an elegant and unique presentation. The main box is white in color, and rectangular in shape, and it includes a hefty amount of information about iFi AC iPurifier, along with its purpose and a few other interesting bits of information.

iFi glued a "Noise Terminator" sticker on the box of the AC iPurifier, which we found quite cute and amusing. The device itself is based on the EU plug in our case, as we're currently situated in Bucharest and wouldn't be able to review AC iPurifier otherwise.

The package contains all the minimum extras necessary to keep the AC iPurifier running, beneath the manuals being the AC iPurifier unit itself, along with a bag of dehumidifying bag. Since it doesn't have any connector besides the power plug, nor needs anything else, the package is simple but elegant.

The AC iPurifier unit is seated in a foam cutout, which keeps it scratch and dust free during transport.

Technical Specifications

All technical data can be found here

iFi also shared this information with their fans

Build Quality/Technical Data

AC iPurifier is built like a tank, being a round, white cylinder which is meant to be plugged in the power mains of your audio setup. Our unit comes with the EU / Romanian standard power plug, but there are variations for other countries as well.

The top of the unit presents two LED lights, both of which can shine both green and red. The first light is the Polarity light, which indicates whether the AC iPurifier is plugged in the correct way, and we managed to experiment a bit with this, seemingly there being a correct and a wrong polarity possible in a power outlet. The second LED light on top of the iFi iPurifier is an "Earth" LED, which basically indicates whether the power outlet has grounding and whether that is wired properly. After experimenting with it, we noticed that the power outlets in Bucharest do have grounding, and that they are indeed wired correctly, allowing for iFi iPurifier to function correctly.

iFi iPurifier is meant to clean the AC power mains and to eliminate any noise which may arise as a result of irregular power. Since we are doing the tests in Bucharest, this is a place not known for clean or coherent power, and we have blackouts once or twice each month, a lot of industrial machinery being connected to the same power lines as our precious audio setups. In this situation, AC iPurifier comes in really handy, as we know we already have a wide variation in the power factor. Voltage surges might be an issue as well here, and iFi AC iPurifier is really handy to protect against those.

Technically, all power should come in clean and should be regulated strictly, but having very expensive and very sensitive speaker setups means that those can react to fine changes in voltage and power delivery, especially when it comes to speaker setups which are always connected to the power mains. If there is no grounding connection for those speakers, or if that grounding isn't done correctly, there will always be a humming noise coming from them, which can be quite quiet, or which can become quite loud, sometimes being considerably louder than the noise floor of a listening setup or of a song, resulting in actual noise which can be heard throughout a song.

To properly understand noise which can be induced by Voltage Variation, one first needs to understand how AC works, or how Alternative Current works. There is a wikipedia article explaining those things in detail here

AC iPurifier basically eliminates all of the issues that are brought on by AC and usage of high-gain, high-precision and sensitive Audio Equipment, being a very user friendly all-in-one solution for cleaning the mains.

Sound Quality

It is extremely complicated to say that we can take any kind of objective measurements of AC iPurifier with the equipment we have available at this moment, and even the best speakers we have right now, which are Edifier S1000DB, are not the most revealing or sensitive pieces of equipment there are, so the final results might be quite different for certain setups.

This time I had my girl help me with those tests. Since we could do the tests together, having the AC iPurifier connected to the same mains as my laptop, Monitor and my speaker setup, we tried to write our thoughts separately and then compiled them for this review.

All of the tests have been done using Edifier S1000DB Speaker setup, in a Bucharest apartment, at moderate to very high listening levels.

Starting with the bottom end, there is a small trace of more precision to the bass, especially when it comes to the upper mid-bass where it feels a tad cleaner and more precise with less bloat amounts.

In the midrange, each musical note seems to have a bit more definition, with every single musical note seemingly having better definition, each micro-texture from an electric guitar bearing a better definition and resolution, more details being presented to the listener, and with slightly less noise.

In the treble, the high notes seem to come a tad smoother with less overall noise and harmonic distortion. Since the tests were taken at very high listening levels, the integrated amplifier in S1000DB were clearly able to reveal those differences better, being under higher gain, having more voltage running through them, subsequently being more prone to noise and other similar issues.

The soundstage seems to be larger with AC iPurifier, the better resolution and detail in the midrange and treble helping shape the soundstage with a larger overall presentation, along with a deeper one. Since the S1000DB is a very specific speaker, AC iPurifier seems to also help it gain a blacker background, but then again, the power mains in Bucharest are not very clean, and other listeners might experience widely different results with different speaker setups and different levels of AC power inherent noise.

Another thing we noticed through our tests is that the timing / ADSR of each musical note seemed a tad better, with a bit better dynamics, but this might be a subsequent result of lowering the noise floor rather than a standalone result on its own. Microtextures, especially those presented in Mindless Self Indulgence synths seem to have considerably better resolution and to be better resolved. The guitars in Metallica's music bear quite the improvement, and the vocals in Pop music, like Melanie Martinez feel more natural and seem to be presented better.

The hum coming from S1000DB is also eliminated well when using AC iPurifier, but it should be noted that S1000DB doesn't have any Grounding in their power line, being a self-powered speaker without grounding, although our typical power plugs do have grounding, so AC iPurifier does a good job there as well, electronic music, like The Glitch Mob being presented with better bass definition. A different, better speaker / amplifier setup would present a different result but with self-powered speakers, the difference is there, at least in our experiment.

Value and Conclusion

At the end of the day, we need to carefully consider what we're presented with. iFi AC iPurifier is a very handy product, which can help eliminate all noise that is creeping into one's music from the power mains, along with the typical amplifier hum when the ground connection is missing.

It is not a very expensive product, being around 130$ in most places, and it offers quite a few services. Considering that most people own speaker setups much more expensive than this, AC iPurifier has a fairly good value and offers quite an excellent service.

One of the best parts about AC iPurifier is the surge protection, being like a second fuse you can add in your system to protect your investment and expensive speaker setup, Many people have setups which are worth thousands, iPurifier being surely welcome to help protect their investment.

At some point I considered giving the AC iPurifier to an uncle who has much more expensive speaker setups, but my girl told me that this one power cleaner has to stay in our system as she really likes the improvements it brings in our listening setup, and who am I to argue after all? I love having better protection and noise removal for both my listening experience, and the extra safety for my electronic devices.

At the end of the day, one should take iFi AC iPurifier for what it is, a very user-friendly solution which can bring serious improvements in sound, by cleaning the AC mains, which is able to analyse the polarity and the grounding of your home, along with offering one of the best prices for this type of products, most power conditioners costing many times the price of iFi AC iPurifier, without always offering the same amount of features or safety (the extra surge protection sure comes in handy).

We can totally recommend someone to look into iFi AC iPurifier as a power conditioner / mains noise removal / extra surge protection, and especially at loud listening levels and when the power is not exactly clean, this is surely going to have a positive impact on your overall listening experience, without costing a fortune.

We hope our review is helpful to you!

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Great review, and couldn't agree more! I finally got mine in the mail today and am quite happy with the improvements!
Bard Rich
Bard Rich

Im using ifi ac ipurifier in my audio system. Im experiencing polarity light turn red especially during night time, but green light during the day. It is normal? Any major problem that i should worried about. Any effect on my audio set up?. Another thing , this product is to detect noise or filtering the noise from the electricity source?
Hope you can help me on this matter

Hope you can help me on this matter
Dobrescu George
Dobrescu George
@Bard Rich - It should not be an issue, although it is an odd one that it would turn red during the night. It is made to filter noise, not just detect.