ISOTEK EVO3 Aquarius Power Conditioner Review

[LEFASR160]

Indeed it would be. But it is an artifact of rectification and would be present whether the incoming signal had zero distortion or not.

@DonR @amirm So now that we can agree that any sine wave frequency fed into the power supply will by necessity cause a ripple at twice the input frequency after it is rectified....consider a deformed sine wave consisting of a Fourier sum of other sine waves of various amplitudes and various frequencies. The Power Supply will then, as an artifact of rectification, produce a sum of ripples equal to twice the frequency of each wave. So if the incoming AC is devoid of those other sine waves (i.e. no distortion---a so called pure sine wave) those additional ripples will be gone. So why not feed a perfect sine wave into one's power supply that is trying to produce DC ? Amir will say even if it is there it will have no effect on the Audio quality. But each PS is different due to different PSRR's with different amplitudes of ripple production. So why not test various power supply designs (not different power generators) to see if a pure sine wave AC produces any better Audio result than say a very deformed sine wave using his 9801 instrument and not a consumer power regenerator ?

 

[amirm]

@amirm Your experiments showed no cleaning in the audio band but for only one or two power supplies in one or two electronic components. You don't need a power conditioner or power regenerator to do the testing if you use your 9801. How do you know that another power supply in another electronic gear, a power supply that has a terrible a PSRR, will do the same ? You haven't shown that. Sorry, no cigar.

I have explained half a dozen times. You seem to not want to read and understand. Once more, testing the output of this power filter shows that it can NOT filter AC mains noise. Ergo, it can't impact the audible noise in a device, period. The audio tests just confirm this. The root of the problem is that none of these boxes are able to get rid of noise and harmonic distortion of mains in audible band.

This is the fundamental reason why test after test of audio products (all different) with many power conditioners doesn't produce any difference. They all have one thing in common: they don't do much filtering of AC mains to eliminate the harmonic distortion and noise in any meaningful way. So even if the power supply was wide open with no filtering, these boxes would do nothing for you.

Now watch you come back and repeat the same illogical argument.

 

[amirm]

@amirm Different power supplies have different power supply rejection ratios.

What? PSRR is a rating for the device being fed by a power supply. Not the power supply itself. If you are not understanding this, then you confirm what I said: that audiophiles go by their lay intuition rather than any knowledge of engineering. You lecture me on science but you don't even know the ABCs of what we are talking about. Take the time to learn the topic or asks questions if you don't understand. Don't pretend to know but then get caught up this way.

 

[amirm]

@DonR @amirm So now that we can agree that any sine wave frequency fed into the power supply will by necessity cause a ripple at twice the input frequency after it is rectified....consider a deformed sine wave consisting of a Fourier sum of other sine waves of various amplitudes and various frequencies. The Power Supply will then, as an artifact of rectification, produce a sum of ripples equal to twice the frequency of each wave. So if the incoming AC is devoid of those other sine waves (i.e. no distortion---a so called pure sine wave) those additional ripples will be gone. So why not feed a perfect sine wave into one's power supply that is trying to produce DC ?

First, where do you get such a perfect AC waveform? Box makers want you to think this but even power regenerators have fair bit of distortion as I have shown. And forget about any useful filtering in the power conditioners, and filters.

Second, what is easier? Filtering the noise at very low amplitude of 3 to 50 volt post rectification or your AC mains that peaks to 338 volts in 240 volt countries? Don't you think if it was cheaper and easier to filter the AC, the audio equipment maker would put that in the box they sell you? Filter components rated for such high voltages are extremely large and expensive compared to their counterparts in power supplies of audio gear.

And remember, even pure AC at 50 and 60 Hz will still create spikes at 2X their frequencies post rectification. And those spikes would be far higher in amplitude because it is the primary tone:

To the extent you clean up the "wanted" signal above, don't you think you have by far cleaned up the harmonics of the "unwanted" as well?

Really, you are wasting our time trying to create doubt here. This dog don't hunt. Go and ask manufacturers to show you data to prove your points.

 

[LEFASR160]

You are wrong there as well for the same reasons. Full dashboard with detail was provided unlike your claim that it was just "SINAD." In addition, I created highly distorted AC waveforms and still showed no difference: https://www.audiosciencereview.com/...ac-distortion-noise-on-audio-equipment.25501/

I suggest not continuing to shoot from the hip causing me to point out obvious things like this. Please read the reviews carefully to fully understand their nature and not make empty excuses for these products.

@amirm Like I said before, I previously read what you measured and I believe I understood exactly what you did and your results and conclusions. You did not look at different power supply designs in different gear. I know you think it doesn't (or shouldn't) matter but assuming that is prejudicial and unscientific. Doing it on only 1 or two PS is just not good enough. You should test different Power Supply designs in different devices that have different power supply rejection ratios.

 

[LEFASR160]

First, where do you get such a perfect AC waveform? Box makers want you to think this but even power regenerators have fair bit of distortion as I have shown. And forget about any useful filtering in the power conditioners, and filters.

Second, what is easier? Filtering the noise at very low amplitude of 3 to 50 volt post rectification or your AC mains that peaks to 338 volts in 240 volt countries? Don't you think if it was cheaper and easier to filter the AC, the audio equipment maker would put that in the box they sell you? Filter components rated for such high voltages are extremely large and expensive compared to their counterparts in power supplies of audio gear.

And remember, even pure AC at 50 and 60 Hz will still create spikes at 2X their frequencies post rectification. And those spikes would be far higher in amplitude because it is the primary tone:

To the extent you clean up the "wanted" signal above, don't you think you have by far cleaned up the harmonics of the "unwanted" as well?

Really, you are wasting our time trying to create doubt here. This dog don't hunt. Go and ask manufacturers to show you data to prove your points.

@amirm you were the one who provided the "pure sine wave" with your 9801. That was your reference or best AC and you said that a power regenerator approximated it.

 

[amirm]

@amirm Like I said before, I previously read what you measured and I believe I understood exactly what you did and your results and conclusions. You did not look at different power supply designs in different gear. I know you think it doesn't (or shouldn't) matter but assuming that is prejudicial and unscientific. Doing it on only 1 or two PS is just not good enough. You should test different Power Supply designs in different devices that have different power supply rejection ratios.

If devices have poor PSRR, how come many measure so superbly? With no sign of any mains level noise? I have probably 50+ DACs at all price points in the top category of all DACs tested. All are measured using ordinary mains input. My state of the art audio precision analyzer has zero need or requirement for AC filtering.

Every circuit designer is mindful of the fact that AC is not clean and that filtering (sometimes multiple stages) is necessary to get clean DC. This is done all the time now in even bargain products.

If your box has AC noise sensitivity -- something we have yet to find -- then get a different audio product. Don't go wasting hundreds if not thousands of dollars to buy these AC products. It is not like they have shown single audio product whose output improved. Don't you think they would if they did have this capability?

They are all hoping to have customers like you: running with random technical terms and lay impressions of engineering to imagine improved sound. And improved sound and sales they get. Don't be a victim. Learn to be smarter than their marketing.

 

[amirm]

@amirm you were the one who provided the "pure sine wave" with your 9801.

No such thing happened. The 9801 has harmonic distortion:

Everything past 60 Hz is unwanted distortion and noise. 0.06% THD+N is not zero.

 

[LEFASR160]

@Amir if you review your prior messages, you were the one who first mentioned and used the term PSRR of the circuit when I asked you to consider different power supplies. I am not a EE like you and I was referring to the power supply itself and its rejection of noise and harmonics introduced to it by the AC mains.

 

[amirm]

Seems like you are keen on repeating the same argument over, and over again. I issued a reply ban. Use the time to re-read the answers given to you. Everything was explained multiple times.

 

[Rottmannash]

The main function of a UPS is to supply power if the mains supply fails. They are cheap to buy with generally a very limited power rating. Due to their low power rating they generally aren’t suitable as a means of cleaning up the mains power supply for Hi Fi use. Wonder if a better method would be a 1:1 isolating transformer, at least it would prevent mains borne DC from affecting your HiFi equipment. Years ago tried a aircraft runway lights mains filter to try and clean up the mains, so far as I could tell it made no difference.
The comments on ‘cheap UPS’ are pertinent to the queries on UPS purchase cost made to AMIR.

But could you land planes with it?

Seems like you are keen on repeating the same argument over, and over again. I issued a reply ban. Use the time to re-read the answers given to you. Everything was explained multiple times.

...finally

 

[voodooless]

It’s really simple: any device that does not show any supply relates harmonics on the dashboard FFT will never ever benefit from a better supply or AC filter. Nor will it suddenly be worse if there is more AC distortion (unless possibly in super extreme cases). And if it does show them, you still don’t know why they are there. It could bleed into the signal in other ways than via the PSU. Best just avoid these devices or accept it rather than spending stupid money on a new PSU or AC cleaner.

What would be the point of testing all PSU types? You should use the PSU that came with your device. If it’s not good enough, don’t buy the device. We already have this data readily available.

 

[solderdude]

And I'd like to see the audio quality test results using test signals of various frequencies from 20 hz to 20khz. I do not believe this was ever done.

The audio device under test is not going to test any different between 1kHz or multitone from a clean or 'dirty' mains power supply.

 

[solderdude]

@DonR It would be 100 hz ripple if the AC line going in was 50 hz. So120 hz ripple is there only because of the incoming AC which is 60 hz as well as the PS's inability to smooth it completely to DC.

Again... you need to read up on rectifiers and understand what the ripple is and why it is there. It seems like you simply do not understand the basics.

Ripple is a function of at least two variables

Ripple is a function of the type of rectifier, input current limit, drawn current, smoothing capacitance.

 

[Suffolkhifinut]

It's pretty obvious that power quality doesn't affect sound quality, so what's the point in messing about further?

How do you know?

 

[Purité Audio]

You look at the measurements of the unit of course, if it has poor mains filtration/regulation that appears in the measurements.
Look at any of A’s reviews.
Keith

 

[TrevC]

How do you know?

All electronics is powered by DC!

 

[Suffolkhifinut]

You look at the measurements of the unit of course, if it has poor mains filtration/regulation that appears in the measurements.
Look at any of A’s reviews.
Keith

Mains quality isn‘t the same everywhere, it’s much worse in heavy industrial areas. In no way doubting AMIR’s competence or measurement technique, would the results be the same in a different location?
If we take the example of a heavy duty water filtration system in an area with a clean water supply it would have little or no effect. Use it in an area where the water is heavily polluted and the outcome would be very different.

 

[Suffolkhifinut]

All electronics is powered by DC!

DC as in rectified AC, not the same as DC from a battery which is ripple free and free from mains borne pollution.

 

[TrevC]

DC as in rectified AC, not the same as DC from a battery which is ripple free and free from mains borne pollution.

No difference, apart from a tiny ramp waveform. DC as in rectified direct current with all mains borne 'pollution' (LOL) removed. How can you tell? Silence when nothing is playing or a 'scope. Or you can read Amir's reviews and try to understand.