PS Audio Noise Harvester AC Cleaner Review

[Judas]

If I cross my index and ring fingers (try it!) and rub them up and down my nose, I feel TWO noses. Your (neurological) mileage may vary.

My nose is two big.
if you sit on a whoopee cushion you'll think have flatulence. I'm just saying.

 

[mansr]

My nose is two big.

 

[mhardy6647]

A typical cosmetic product in the UK claims that it results in ‘up to 100%‘ elimination of grey hairs. Clearly, this claim includes the number 0.

heck, it might even be construed to include negative, irrational, and imaginary numbers.

 

[mhardy6647]

I can answer that. PS Audio hates tubes.

They might hate 'em, but they must be hatin' all the way to the bank (to paraphrase Liberace).
https://www.psaudio.com/bhk-preamplifier/
https://www.psaudio.com/stellar-m1200-mono-amplifier/

 

[Judas]

Emotiva hates tubes also. Yet they tried to purchase Carver tube amps. On the off chance you didi not know they contracted out to Bascom King to design thier hybrid tube amp. Hence the the name BHK.

 

[mhardy6647]

Emotiva hates tubes also. Yet they tried to purchase Carver tube amps. On the off chance you didi not know they contracted out to Bascom King to design thier hybrid tube amp. Hence the the name BHK.

Yes, but 1) they did it (contracted with King) and 2) they then deigned to put the PS Audio nameplate on it.
And then 3) there's the Stellar M1200 -- not seein' a BHK on that... but there be tubes in them.

The M1200’s designer, PS Audio engineer Darren Myers, wanted to see what would happen when he combined one of the world’s highest power amplifier stages with a rich and warm vacuum tube input stage—the results set us all back on our heels. This hybrid approach combines the best of today’s technology with time-honored techniques leveraging PS Audio’s forty-plus years of experience.

Thoughts?

 

[mansr]

Thoughts?

It may be legal in Colorado, but they should probably smoke a bit less of it anyway.

 

[Judas]

Yes, but 1) they did it (contracted with King) and 2) they then deigned to put the PS Audio nameplate on it.
And then 3) there's the Stellar M1200 -- not seein' a BHK on that... but there be tubes in them.



Thoughts?

Ok to be more specific it was Paul McGowan who hates tubes. But I think we can agree he is the face of PS Audio. I for one am glad the market forced them to admit the superiority of tubes. I would wager Paul did not design the M1200.
Edit: You already pointed out it was Darren Myers.

 

[Count Arthur]

I for one am glad the market forced them to admit the superiority of tubes.

I'm not sure "the market" provides any information about the quality or efficacy of products. There have been many products that were heavily promoted or that became fashionable and sold lots of units, but were objectively poor quality or value.

For example the original Beats headphones sold in huge quantities, and although I never tried them personally, it was widely reported in the Hi-Fi press that they weren't particularly good and offered very poor value when compared to headphones from other brands, like Sennheiser, AKG, Audio Technica, etc., but it didn't seem to effect their sales.

It's a myth that "the market" determines that good products become the most popular, while poorly performing and poor value products no longer get produced in some kind of Darwinian natural selection process. Purchasing decisions are rarely rational, if they were, we wouldn't see quite so many large 4WD off-road vehicles in our city centres and Nike wouldn't sell many £300.00 sports shoes to people that barely walk anywhere, let alone do sport.

 

[Jmudrick]

With Furutech's version "no A-B test is necessary.. " and its got nano crystals.

https://www.monoandstereo.com/2021/02/furutech-ncf-clear-line-ac-optimizer.html

 

[ta240]

I can answer that. PS Audio hates tubes.

Of course, that is likely only until he finds a way to make money off of them as output tubes. He quickly changed his mind on input tubes as soon as there was a viable product with them that he could sell for a lot of money. The thing he probably truly hates about output tubes is that they are able to take any of his high end market share.

He was going to wire the new listening room with mogami wire until audioquest convinced him to use their wire and now... shockingly... he sells $21,000 speaker wire for them. Sure, maybe I'm just cynical and he was so blown away by how much better their wires sound and wanted to share that with the world. But his original listening room was so good it made people cry so just how much better is the crazy expensive (free to him) wire making it sound.

Heck, he sells a $130 power cable that has been "hand selected to perfectly match the sprout", which is a $700 amplifier. Nearly 20% of the price of the amp added in a power cable! Audio quality does not, in any way, rule his recommendations.
When they did their own unboxing video on the sprout and the guy mentioned replacing the 'cheap' power cord it came with, the comments ripped them a new one for not only including what had to be a sub-standard power cord but also pushing buying an expensive cord for an inexpensive amp, he quickly edited that part out of the video and reuploaded it. But the power of money made them more subtly push spending big on a power cord for the little amp.

...It's a myth that "the market" determines that good products become the most popular, while poorly performing and poor value products no longer get produced in some kind of Darwinian natural selection process. Purchasing decisions are rarely rational, if they were, we wouldn't see quite so many large 4WD off-road vehicles in our city centres and Nike wouldn't sell many £300.00 sports shoes to people that barely walk anywhere, let alone do sport.

Very well said. In a world where fashion along with brand name plays a huge role in electronics purchases and online hype drives sales far more than product performance, complete crap can be very popular. Just look at the popularity cycle of products as "zeos said this is the best... ever" or "the audiopheliac said..." making a product sell out and then that product fades as they hype the next product.

With Furutech's version "no A-B test is necessary.. " and its got nano crystals.

https://www.monoandstereo.com/2021/02/furutech-ncf-clear-line-ac-optimizer.html

What? There is an 'article' hidden within over 70 advertisements on a single page?!?!

but it has "The special T10 tamper-proof stainless steel self-tapping screws and washers " so it must be good. Just like the latch on the restroom door.... If you have to list the screws on your product being tamper-proof as one of its 5 features, then there isn't much else to that product worth noting.

With the classic line "As you can read throughout the review the newly gained attributes are not exactly marginal." it begs the question of why wouldn't high end amp manufactures build this into their amps. A question that was asked of PSAudio and their answer was "people might not want the flashing blue LED in their amp". A great answer that sidesteps the question when there would be no reason that their amps that cost thousands of dollars shouldn't have several of those built in, if it really makes an improvement. Especially since they could easily hide the LED light or... even use something other than an LED to drain the collected power. But only if it really did make an improvement.

 

[001]

So this is the opposite of a Harley Davidson motorcycle, which efficiently converts energy into noise?

And who can forget the original mono to stereo converter? That's right any very young person, possibly around the baby stage. You all know that food goes into 1 place, and when playing the ever-fun-for-everyone "vomit comet" game, said small person converts mono into stereo. (Please wait till everything is dry before cleaning the carpet). Kids really *are* the greatest.

 

[krott5333]

if you can't hear the difference then your system just isn't transparent or dynamic enough. [/extreme sarcasm, don't kill me]

 

[egellings]

Some products sell on "cool factor" more than anything else, and quality may vary. Beats cans are an example. Cool, but not sonically outstanding.

 

[GMG]

@amirm,
Thanks for the insightful review.
obviously this little device can do very little to reduce any significant noise on the mains.
that said, it does seem to do a decent job of indicating that such noise exists. Perhaps some/most of that noise is inherently addressed by well designed equipment.
I purchased this device for that purpose. It is not that expensive and I just wanted a simple indication of the quality of my mains.
what I found is that my mains is quite clean (to the extent that this device can detect and indicate of course). Most of the time I got no blinking at all. Some times there is a single blink every few minutes. Maybe this is due to the fact that I have a dedicated power line for my stereo.
The only time it goes crazy is when I turn on one particular air conditioner (despite the separate power line). This particular air conditioner is different then the rest of the units in my house. It is an inverter air conditioner and as far as I know it means it manipulates AC/DC in order to be more energy efficient. This manipulation obviously leaks back a lot of noise back to the main.
even though this noise may not have an audioable effect on my well designed system, I would very much like to avoid it.
can you recommend any sort of filter that I can add inline to the power plug of the air conditioner that will filter out such noise at the source?

would this help:

https://www.aliexpress.com/item/327...000&pvid=865655bc-de35-4d28-981d-06b0d893cd35

 

[MediumRare]

@amirm,
Thanks for the insightful review.
obviously this little device can do very little to reduce any significant noise on the mains.
that said, it does seem to do a decent job of indicating that such noise exists. Perhaps some/most of that noise is inherently addressed by well designed equipment.
I purchased this device for that purpose. It is not that expensive and I just wanted a simple indication of the quality of my mains.
what I found is that my mains is quite clean (to the extent that this device can detect and indicate of course). Most of the time I got no blinking at all. Some times there is a single blink every few minutes. Maybe this is due to the fact that I have a dedicated power line for my stereo.
The only time it goes crazy is when I turn on one particular air conditioner (despite the separate power line). This particular air conditioner is different then the rest of the units in my house. It is an inverter air conditioner and as far as I know it means it manipulates AC/DC in order to be more energy efficient. This manipulation obviously leaks back a lot of noise back to the main.
even though this noise may not have an audioable effect on my well designed system, I would very much like to avoid it.
can you recommend any sort of filter that I can add inline to the power plug of the air conditioner that will filter out such noise at the source?

The Aurora Borealis tells us regularly there are cosmic rays bombarding the Earth. As long as you do not exit your spacecraft while wearing just a tee shirt you will probably be fine. The same goes for your air conditioner. Please do not lick the circuit breakers while it is running. Otherwise, your audio equipment will be fine.

 

[DigitizeNY]

This is a review and detailed measurements of the PS Audio Noise Harvester and AC Cleaner. It is on kind loan from a member and sells for $99.

The harvester is a bit bigger and uglier than typical phone charger:

View attachment 69147

Claim to fame is that AC noise is captured gradually and then discharged all of a sudden into the LED on the right to get rid of it:

View attachment 69148

One wonders why a sudden discharge wouldn't be bad for your sound versus a gradual/constant thing!

As to discharging "all the unwanted noise" company shows no specifications or measurements to demonstrate that. It is trivial to measure noise so not do that?

Also, I see no indication of safety regulation on the device and on the website. It is one thing to lack such marks for low voltage devices but an entirely different matter when you plug something in to mains and leave it there. A safety flaws could lead to fire or worse. What would this thing do for example if a powerful external surge arrives? Does it open up gracefully or short and cause smoke?

Does It Do Anything?
A lot of tweaks sold to audiophiles make claims that follow the laws of another universe so we can't use our tools in this universe to test them. Here though, we can. AC mains is at 50 or 60 Hz. A filter better not touch these frequencies or you would loose the very energy you need for our device to function! As a result, filtering will be at some higher frequency, often well above hearing range making them useless for improving audio.

To determine the filter range, I set my Audio Precision to produce 21 volts output and captured and plotted that using very wideband response (1 MHz). I then inserted the Harvester in the middle to see the effect:

View attachment 69149

Hey! There is some good news here. There is filtering that occurs in the audio band and indeed, we have reduction of frequencies above 500 Hz with best response (naturally) at higher frequencies. There is a resonance causing that peaking but otherwise, we have about 20 dB of reduction. The harvester was blinking away happily saying it was doing its job.

Would this do us some good? Well, let's look at the spectrum of AC in the power strip that I use to power my analyzer, the PC and anything I review. To not kill myself or the analyzer, I used a simple AC transformer to bring the voltage down. Otherwise everything is the same:

View attachment 69150

In blue is the spectrum of the AC mains. Instead of the ideal single 60 Hz tone, we have a myriad of other tones. Highest peak is nearly -30 dB. This result in a THD+N of nearly 3%.

Once I plug in the Harvester, we get the graph in red. Yes, it almost looks identical because as I showed before, it doesn't do anything below 500 Hz. Unfortunately that spectrum between 60 and 500 Hz has most of our distortion and noise. What is above that has far lower amplitude.

Even in high frequencies we don't get much attenuation because the amount of energy harvested and dissipated by this box is too little. Imagine what it takes to power an LED for a fraction of a second. It is probably in microamps which would mean nothing in grand scheme of things. No wonder then that THD+N doesn't change (the number varies fair bit so don't focus on decimal places).

In addition to frequency domain, we can also look at the waveform in "time domain:"

View attachment 69155

We can easily see the effects of 3% distortion in how the tops of the sine wave are distorted (flattened mostly). Sadly, the Harvester does nothing to turn our ugly sine waves into pretty ones. With or without, the shape is the same.

At this point we have fully characterized the device. It is a low pass filter with very negligible effectiveness. But maybe it performs some magic that escapes these measurements but shows up in audio devices so let's test them with and without the Harvester.

AC Cleaner Effect on Audio Performance
Let's start with the most sensitive and highest performance "audio" device I have which is my Audio Precision APx555 analyzer. I put it in the loopback mode and measured its own distortion+noise over time. After a bit of time, I plugged in the Harvester and then took it out. This is the results:

View attachment 69151

As you see, it made no difference whatsoever even though we are measuring distortion and noise that is whopping -123.5 dB below full level! Why doesn't it care? Because it designed with the assumption that AC mains is never clean or remotely so. All the necessary filtering is performed internally which is a lot easier when dealing with low voltage DC, than high voltage mains AC.

OK, so that is a $28,000 analyzer so let's step down to a much more reasonable $500 Topping A90 which I recently reviewed:

View attachment 69152

The harvester blinking away saying it is doing something. But again, in super sensitive measurements representing far lower threshold than our hearing, there is no effect on noise+distortion at all.

Let's go even cheaper to $99 JDS Labs Atom DAC:
View attachment 69153

We can see how sensitive our measurement system is in detecting very small variations in performance of Atom DAC. Clearly there is some "noise" there to clean up but the Harvester does nothing for us.

Maybe we shouldn't use high-performance audio devices. For that, let's use the Schiit Modi 2 Uber DAC:

View attachment 69154

Not... one... thing... different! Surely the Harvester should have gotten lucky by now and did something. But it did not.

Listening Tests
Folks always come back and say "but I hear a difference, you should use your ears." So that is what I did. On the same computer used for above, I use an RME ADI-2 DAC V2. Into that I use an Ether CX headphone. I plugged in and unplugged the Harvester multiple times but could not detect any difference whatsoever.

If you are hearing a difference, turn away from your power strip, have a loved one plug the device in and out at random times and have you raise your hand when you think it is plugged in. After just a minute or two, you will get the right answer which is there is no audible difference. Your brain concludes that there is less noise because you are told there is less noise with this device and hence you "hear it." Lack of change in audio waveform reaching your ears be damned.

Conclusions
In some sense it is a relief to find an audio tweak that we can analyzer and characterize what it does. It indeed filters "some noise." That filter is too small to begin with. But importantly is of no use because your good audio devices already filter that noise. Imagine how bad my audio system would sound if the 3% harmonic distortion and noise was let through! Which designer you cherish would sell you an audio device that doesn't do such filtering when it is so easy and cheap to do???

Remember, the company could easily measure noise and show the improvement with their own or other companies' products. But they have not. You wouldn't take a drug with no verification of its efficacy. Why would you trust a company to sell you something to "clean your AC" where no such evidence is not at all?

On top of that, you have a mains operated device which no third-party verification that is safe to be plugged in. As such, it is illegal to sell in probably every western countries if not others.

Be a smart audiophile. Don't put your guard down just because there are positive testimonials for such devices. I don't care how useless an audio device is. Some people will say it performs miracle. These people don't know how to perform a simple, bias controlled test to verify the truth. Don't listen to them. Don't put your guard down.

And before you say everyone who owns one likes it, watch this:

-----------
As always, questions, comments, recommendations, etc. are welcome.

June is turning out to be an expensive month. I will probably be close to shipping back 500 pounds of gear and have spent nearly $1,500 on gear. I can afford it but will feel entirely more positive if you all donate it! https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

 

[DigitizeNY]

This is a review and detailed measurements of the PS Audio Noise Harvester and AC Cleaner. It is on kind loan from a member and sells for $99.

The harvester is a bit bigger and uglier than typical phone charger:

View attachment 69147

Claim to fame is that AC noise is captured gradually and then discharged all of a sudden into the LED on the right to get rid of it:

View attachment 69148

One wonders why a sudden discharge wouldn't be bad for your sound versus a gradual/constant thing!

As to discharging "all the unwanted noise" company shows no specifications or measurements to demonstrate that. It is trivial to measure noise so not do that?

Also, I see no indication of safety regulation on the device and on the website. It is one thing to lack such marks for low voltage devices but an entirely different matter when you plug something in to mains and leave it there. A safety flaws could lead to fire or worse. What would this thing do for example if a powerful external surge arrives? Does it open up gracefully or short and cause smoke?

Does It Do Anything?
A lot of tweaks sold to audiophiles make claims that follow the laws of another universe so we can't use our tools in this universe to test them. Here though, we can. AC mains is at 50 or 60 Hz. A filter better not touch these frequencies or you would loose the very energy you need for our device to function! As a result, filtering will be at some higher frequency, often well above hearing range making them useless for improving audio.

To determine the filter range, I set my Audio Precision to produce 21 volts output and captured and plotted that using very wideband response (1 MHz). I then inserted the Harvester in the middle to see the effect:

View attachment 69149

Hey! There is some good news here. There is filtering that occurs in the audio band and indeed, we have reduction of frequencies above 500 Hz with best response (naturally) at higher frequencies. There is a resonance causing that peaking but otherwise, we have about 20 dB of reduction. The harvester was blinking away happily saying it was doing its job.

Would this do us some good? Well, let's look at the spectrum of AC in the power strip that I use to power my analyzer, the PC and anything I review. To not kill myself or the analyzer, I used a simple AC transformer to bring the voltage down. Otherwise everything is the same:

View attachment 69150

In blue is the spectrum of the AC mains. Instead of the ideal single 60 Hz tone, we have a myriad of other tones. Highest peak is nearly -30 dB. This result in a THD+N of nearly 3%.

Once I plug in the Harvester, we get the graph in red. Yes, it almost looks identical because as I showed before, it doesn't do anything below 500 Hz. Unfortunately that spectrum between 60 and 500 Hz has most of our distortion and noise. What is above that has far lower amplitude.

Even in high frequencies we don't get much attenuation because the amount of energy harvested and dissipated by this box is too little. Imagine what it takes to power an LED for a fraction of a second. It is probably in microamps which would mean nothing in grand scheme of things. No wonder then that THD+N doesn't change (the number varies fair bit so don't focus on decimal places).

In addition to frequency domain, we can also look at the waveform in "time domain:"

View attachment 69155

We can easily see the effects of 3% distortion in how the tops of the sine wave are distorted (flattened mostly). Sadly, the Harvester does nothing to turn our ugly sine waves into pretty ones. With or without, the shape is the same.

At this point we have fully characterized the device. It is a low pass filter with very negligible effectiveness. But maybe it performs some magic that escapes these measurements but shows up in audio devices so let's test them with and without the Harvester.

AC Cleaner Effect on Audio Performance
Let's start with the most sensitive and highest performance "audio" device I have which is my Audio Precision APx555 analyzer. I put it in the loopback mode and measured its own distortion+noise over time. After a bit of time, I plugged in the Harvester and then took it out. This is the results:

View attachment 69151

As you see, it made no difference whatsoever even though we are measuring distortion and noise that is whopping -123.5 dB below full level! Why doesn't it care? Because it designed with the assumption that AC mains is never clean or remotely so. All the necessary filtering is performed internally which is a lot easier when dealing with low voltage DC, than high voltage mains AC.

OK, so that is a $28,000 analyzer so let's step down to a much more reasonable $500 Topping A90 which I recently reviewed:

View attachment 69152

The harvester blinking away saying it is doing something. But again, in super sensitive measurements representing far lower threshold than our hearing, there is no effect on noise+distortion at all.

Let's go even cheaper to $99 JDS Labs Atom DAC:
View attachment 69153

We can see how sensitive our measurement system is in detecting very small variations in performance of Atom DAC. Clearly there is some "noise" there to clean up but the Harvester does nothing for us.

Maybe we shouldn't use high-performance audio devices. For that, let's use the Schiit Modi 2 Uber DAC:

View attachment 69154

Not... one... thing... different! Surely the Harvester should have gotten lucky by now and did something. But it did not.

Listening Tests
Folks always come back and say "but I hear a difference, you should use your ears." So that is what I did. On the same computer used for above, I use an RME ADI-2 DAC V2. Into that I use an Ether CX headphone. I plugged in and unplugged the Harvester multiple times but could not detect any difference whatsoever.

If you are hearing a difference, turn away from your power strip, have a loved one plug the device in and out at random times and have you raise your hand when you think it is plugged in. After just a minute or two, you will get the right answer which is there is no audible difference. Your brain concludes that there is less noise because you are told there is less noise with this device and hence you "hear it." Lack of change in audio waveform reaching your ears be damned.

Conclusions
In some sense it is a relief to find an audio tweak that we can analyzer and characterize what it does. It indeed filters "some noise." That filter is too small to begin with. But importantly is of no use because your good audio devices already filter that noise. Imagine how bad my audio system would sound if the 3% harmonic distortion and noise was let through! Which designer you cherish would sell you an audio device that doesn't do such filtering when it is so easy and cheap to do???

Remember, the company could easily measure noise and show the improvement with their own or other companies' products. But they have not. You wouldn't take a drug with no verification of its efficacy. Why would you trust a company to sell you something to "clean your AC" where no such evidence is not at all?

On top of that, you have a mains operated device which no third-party verification that is safe to be plugged in. As such, it is illegal to sell in probably every western countries if not others.

Be a smart audiophile. Don't put your guard down just because there are positive testimonials for such devices. I don't care how useless an audio device is. Some people will say it performs miracle. These people don't know how to perform a simple, bias controlled test to verify the truth. Don't listen to them. Don't put your guard down.

And before you say everyone who owns one likes it, watch this:

-----------
As always, questions, comments, recommendations, etc. are welcome.

June is turning out to be an expensive month. I will probably be close to shipping back 500 pounds of gear and have spent nearly $1,500 on gear. I can afford it but will feel entirely more positive if you all donate it! https://www.audiosciencereview.com/forum/index.php?threads/how-to-support-audio-science-review.8150/

Lol, surely if this contraption did anything remotely beneficial to the sound quality of the audio equipment connected to the AC supply, the effect itself would be enough proof that the thing was "harvesting" the noise properly. No stupid flashing light necessary! Just a silly light to boost the placebo effect a little more! (And to boost McGowan's bank account, obvs!)

 

[formdissolve]

Did you ever review that PS Audio Power Plant? My friend wants to buy one because he's convinced he needs it.. but I want to save him thousands of dollars!

 

[win]

Did you ever review that PS Audio Power Plant? My friend wants to buy one because he's convinced he needs it.. but I want to save him thousands of dollars!

He won't be able to build a highly resolving system without it.